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Digital Earth Workbench: Global Sea Surface Temperature
NSDL National Science Digital Library
The Digital Earth Workbench is an interactive application that runs on a SGI Onyx Infinite Reality system and is controlled by an Immersive Workbench, tracked stereo glasses, and a tracked wand. The application allows an unprecedented freedom to roam georeferenced datasets at multiple resolutions and timescales. This animation is one of a series of direct creen captures of the application in operation. The occasional menu appearance denotes direct intervention by the operator to add or delete data or to activate a new control option.
Maher, Steve
Soil moisture from temperature measurements at the Earth's surface, update
NASA Technical Reports Server (NTRS)
Soil moisture budgets at the Earth's surface were investigated based on soil and atmospheric temperature variations. A number of data sets were plotted and statistically analyzed in order to accentuate the existence and the characteristics of mesoscale soil temperature extrema variations and their relations to other parameters. The correlations between diurnal temperature extrema for air and soil in drought and non-drought periods appear to follow different characteristic patterns, allowing an inference of soil moisture content from temperature data. The recovery of temperature extrema after a precipitation event also follows a characteristic power curve rise between two limiting values which is an indicator of evaporation rates. If these indicators are applied universally to regional temperature data, soil moisture content or drought conditions can be inferred directly from temperature measurements.
Welker, J. E.
A New Estimate of the Earth's Land Surface Temperature History
NASA Astrophysics Data System (ADS)
The Berkeley Earth Surface Temperature team has re-evaluated the world's atmospheric land surface temperature record using a linear least-squares method that allow the use of all the digitized records back to 1800, including short records that had been excluded by prior groups. We use the Kriging method to estimate an optimal weighting of stations to give a world average based on uniform weighting of the land surface. We have assembled a record of the available data by merging 1.6 billion temperature reports from 16 pre-existing data archives; this data base will be made available for public use. The former Global Historic Climatology Network (GHCN) monthly data base shows a sudden drop in the number of stations reporting monthly records from 1980 to the present; we avoid this drop by calculating monthly averages from the daily records. By using all the data, we reduce the effects of potential data selection bias. We make an independent estimate of the urban heat island effect by calculating the world land temperature trends based on stations chosen to be far from urban sites. We calculate the effect of poor station quality, as documented in the US by the team led by Anthony Watts by estimating the temperature trends based solely on the stations ranked good (1,2 or 1,2,3 in the NOAA ranking scheme). We avoid issues of homogenization bias by using raw data; at times when the records are discontinuous (e.g. due to station moves) we break the record into smaller segments and analyze those, rather than attempt to correct the discontinuity. We estimate the uncertainties in the final results using the jackknife procedure developed by J. Tukey. We calculate spatial uncertainties by measuring the effects of geographical exclusion on recent data that have good world coverage. The results we obtain are compared to those published by the groups at NOAA, NASA-GISS, and Hadley-CRU in the UK.
Muller, R. A.; Curry, J. A.; Groom, D.; Jacobsen, B.; Perlmutter, S.; Rohde, R. A.; Rosenfeld, A.; Wickham, C.; Wurtele, J.
Earth and Mars: evolution of atmospheres and surface temperatures.
Solar evolution implies, for contemporary albedos and atmospheric composition, global mean temperatures below the freezing point of seawater less than 2.3 aeons ago, contrary to geologic and paleontological evidence. Ammonia mixing ratios of the order of a few parts per million in the middle Precambrian atmosphere resolve this and other problems. Possible temperature evolutionary tracks for Earth and Mars are described. A runaway greenhouse efect will occur on Earth about 4.5 aeons from now, when clement conditions will prevail on Mars. PMID:17756316
Sagan, C; Mullen, G
Earth Observatory Data and Images - Sea Surface Temperature
NSDL National Science Digital Library
Visitors can use sea surface temperature data to build animations that show seasonal and yearly fluctuations, and compare them to data from other selected months and years. The animations can be constructed in map or globe formats and may be viewed on the website or downloaded.
Heat capacity mapping mission. [satellite for earth surface temperature measurement
NASA Technical Reports Server (NTRS)
A Heat Capacity Mapping Mission (HCMM), part of a series of Applications Explorers Missions, is designed to provide data on surface heating as a response to solar energy input. The data is obtained by a two channel scanning radiometer, with one channel covering the visible and near-IR band between 0.5 and 1.1 micrometers, and the other covering the thermal-IR between 10.5 and 12.5 micrometers. The temperature range covered lies between 260 and 340 K, in 0.3 deg steps, with an accuracy at 280 K of plus or minus 0.5 K. Nominal altitude is 620 km, with a ground swath 700 km wide.
Price, J. C.
Digital Earth Workbench: Sea Surface Temperature with Cloud Cover
NSDL National Science Digital Library
The Digital Earth Workbench is an interactive application that runs on a SGI Onyx Infinite Reality system and is controlled by an Immersive Workbench, tracked stereo glasses, and a tracked wand. The application allows an unprecedented freedom to roam georeferenced datasets at multiple resolutions and timescales. This animation is one of a series of direct creen captures of the application in operation. The occasional menu appearance denotes direct intervention by the operator to add or delete data or to activate a new control option.
Maher, Steve
Global relationships among the earth's radiation budget, cloudiness, volcanic aerosols, and surface temperature
NASA Technical Reports Server (NTRS)
Global relationships among the earth's radiation budget, cloudiness, solar constant, volcanic aerosols, and surface temperature are analyzed using data obtained by the Nimbus-7 spacecraft. It was found that these parameters were interrelated on interannual time scales, demonstrating that the interannual variability in the earth's climate (i.e., radiation budget) is detectable and observable by current spaceborne instruments. The degree of global interannual variation is on the order of tenths of percent.
Ardanuy, Philip E.; Kyle, H. L.; Hoyt, Douglas
High Speed Solar Wind Influence on NAO Index and Surface Temperature on Earth
NASA Astrophysics Data System (ADS)
The most important role in the atmospheric circulation in the Northern hemisphere plays the North Atlantic Oscillation (NAO). The NAO index changes the surface air temperature in a typical pattern. This research is about high speed solar wind streams (HSSWS) and their influence on the atmospheric circulation. The NAO index increases when a HSSWS reaches the Earth in all studied cases and this leads to typical surface air temperature changes in short term scale.
Asenovska, Yana
The faint young sun problem. [in regulating surface temperature of early earth
NASA Technical Reports Server (NTRS)
It is shown that the faint young sun problem was most likely solved by an increase in atmospheric CO2 concentration in the earth's atmosphere brought about by the CO2 geochemical cycle. Because the loss process for atmospheric CO2 requires liquid water, and because the earth is continually resupplying atmospheric CO2 by carbonate metamorphism, the surface temperature should never have fallen below the point at which the ocean would freeze. Indeed, the early earth may have been quite warm if carbonate metamorphism was faster and if the continents were originally smaller, so that silicate weathering was inhibited.
Kasting, James F.; Grinspoon, David H.
The Surface Temperatures of the Earth: Steps towards Integrated Understanding of Variability and Change
NASA Astrophysics Data System (ADS)
Surface temperature is a key aspect of weather and climate, relevant to human health, agriculture and leisure, ecosystem services, infrastructure development and economic activity. In a community-based activity, the EarthTemp Network brought together 55 researchers from 5 continents to improve the interaction between scientific communities who focus on particular domains, to exploit the strengths of different observing systems and to better meet the needs of different communities. The Network idenitified key needs for progress towards meeting societal needs for surface temperature understanding and information, which will be reviewed and discussed in this contribution. A "whole-Earth" perspective is required with more integrated, collaborative approaches to observing and understanding Earth's various surface temperatures. It is necessary to build understanding of the relationships of different surface temperatures, where presently inadequate, and undertake large-scale systematic intercomparisons. Datasets need to be easier to obtain and exploit for a wide constituency of users, with the differences and complementarities communicated in readily understood terms, and realistic and consistent uncertainty information. Steps are also recommended to curate and make available data that are presently inaccessible, develop new observing systems and build capacities to accelerate progress in the accuracy and usability of surface temperature datasets.
Matthiesen, Stephan; Merchant, Chris; Rayner, Nick; Remedios, John; H�yer, Jacob L.; Jones, Phil; Olesen, Folke; Roquet, Herv�; Sobrino, Jos�; Thorne, Peter
NSDL National Science Digital Library
This self-contained module on Earth's crust includes a range of fun activities that students can perform in the classroom and at home with family members. They impart important concepts such as observation, identification, measurement, and differentiation.
Science, Houghton M.
No direct correlation between galactic cosmic rays and earth surface temperature
NASA Astrophysics Data System (ADS)
We have searched for a correlation between galactic cosmic rays (GCRs) and global earth surface air temperature (GST) datasets going back to the year 1900. The linear correlation coefficient between GCRs and GST varies erratically, exhibiting both positive and negative values over time scales varying from about 5-20 years. Since the finding of no persistent correlation is not supported by predictive theory but is what one should expect for two random, un-correlated time series, we infer that GCRs do not influence global surface air temperature.
Ahluwalia, H. S.
NSDL National Science Digital Library
This website is part of Visible Earth, which is hosted by the National Aeronautics and Space Administration (NASA), and contains a searchable directory of images, visualizations, and animations of the Earth. This section contains images pertaining to surface processes, including erosion, sedimentation, land temperature, land use, soils, topography, and more. Each image is available in a variety of resolutions and sizes, with a brief description, credit, date, and the satellite that took the image.
Earth System Science at NASA: Teleconnections Between Sea Surface Temperature and Epidemics in Africa
NASA Technical Reports Server (NTRS)
The research carried out in the Earth Sciences in NASA and at NASA's Goddard Space Flight Center will be the focus of the presentations. In addition, one research project that links sea surface temperature to epidemics in Africa will be highlighted. At GSFC research interests span the full breath of disciplines in Earth Science. Branches and research groups focus on areas as diverse as planetary geomagnetics and atmospheric chemistry. These organizations focus on atmospheric sciences (atmospheric chemistry, climate and radiation, regional processes, atmospheric modeling), hydrological sciences (snow, ice, oceans, and seasonal-to-interannual prediction), terrestrial physics (geology, terrestrial biology, land-atmosphere interactions, geophysics), climate modeling (global warming, greenhouse gases, climate change), on sensor development especially using lidar and microwave technologies, and on information technologies, that enable support of scientific and technical research.
Meeson, Blanche W.
Spatial scale dependence of the long-range memory properties of Earth surface temperature
NASA Astrophysics Data System (ADS)
We present a study of the long-range memory properties of the Earth surface temperature. Different spatial scales are analyzed, and it is observed that the persistence of the time series increases with increasing spatial scale. It is also observed that sea surface temperatures are more persistent than land temperatures. The analysis is performed by coarse-graining gridded temperature data, starting out with boxes of 5 x 5 degrees, and then averaging them up to global scales. As a measure of the strength of persistence we have the Hurst exponent, which we have estimated using methods like wavelet variance and maximum likelihood. In the search of an explanation for the differences in the degree of persistence we have studied the strength of the cross-covariances between the temperatures at different locations. If this is strong it will have an impact on the autocovariance function for the average temperature within the area studied. In this way we can see that the spatial covariance is closely linked to the temporal covariance.
Fredriksen, H.; Rypdal, K.; Rypdal, M.; L�vsletten, O.
HoloGlobe: Sea Surface Temperature and Temperature Anomaly on a Flat Earth
NSDL National Science Digital Library
This is one of a series of animations that were produced to be part of the narrated video shown in the HoloGlobe exhibit at the Smithsonian Museum of Natural History and the Earth Today exhibit at the Smithsonian Air and Space Museum.
Strong, Jim; Watters, Tom
HoloGlobe: Sea Surface Temperature and Temperature Anomaly on a Flat Earth (with Dates)
NSDL National Science Digital Library
This is one of a series of animations that were produced to be part of the narrated video shown in the HoloGlobe exhibit at the Smithsonian Museum of Natural History and the Earth Today exhibit at the Smithsonian Air and Space Museum.
Strong, Jim; Mitchell, Horace; Watters, Tom
NSDL National Science Digital Library
Overview: The Earth's Changing Surface SciPack explores how Earth's ever-changing surface is due to continuous natural processes such as tectonic activity, earthquakes, volcanic activities, weathering and erosion, and sedimentation and the reformation of rock. The focus is on topics supporting Standards and Benchmarks related to how and why these processes occur, and how elements cycle through the land, oceans, and atmosphere as a result of these processes. This SciPack looks at Earth as a system that exists in dynamic equilibrium. In addition to comprehensive inquiry-based learning materials tied to Science Education Standards and Benchmarks, the SciPack includes the following additional components: Pedagogical Implications section addressing common misconceptions, teaching resources and strand maps linking grade band appropriate content to standards. Access to one-on-one support via e-mail to content "Wizards". Final Assessment which can be used to certify mastery of the concepts. Learning Outcomes: Earth's Changing Surface: Changing Earth From Within Explain that both Earth's surface and interior are in motion and describe the causes the motion. Describe how heat within Earth comes from two main sources: radioactive decay and residual heat (gravitational energy left over from the formation of Earth). Explain the fact that the vast majority of earthquakes and volcanic activities which occur near plate boundaries are caused by the movement of the plates. Describe that changes on Earth's surface also happen on the ocean floor to create forms such as ocean basins, mountains and volcanoes. Earth's Changing Surface: Sculpting the Landscape Distinguish between changes in Earth's surface that are abrupt, such as earthquakes and volcanoes and changes that happen very slowly such as uplift and wearing down of mountains. Identify rates of landscape formation. Infer from present data that the processes that shape the earth today are similar to events that occurred in the past. Identify agents of change as destructive, constructive, or both. Describe how erosion by way of waves, wind, glaciers, gravity, running water, etc., causes change in geological features. Earth's Changing Surface: Humans as Agents of Change Distinguish natural processes that shape the surface of Earth from human impact factors that change the surface of Earth. Explain how human activities such as river control, mining, and deforestation have had an effect on the shape of Earth's surface. Describe how human activities do not create new processes but cause changes in the rate and scale of natural processes.
National Science Teachers Association (NSTA)
The inner core and the surface heat flow as clues to estimating the initial temperature of the Earth's core
This paper attempts to estimate the temperature of the deep interior of the early Earth. The initial temperature cannot be too high or too low in order to realize the present-day thermal state, such as the surface heat flow and the inner core size. Two constraints have been placed: (1) The age of the core is 4.4�109 years, comprised of
Takesi Yukutake
Earth Exploration Toolbook Chapter: Detecting El Ni�o in Sea Surface Temperature Data
NSDL National Science Digital Library
DATA: Sea Surface Temperature (SST). TOOL: My World GIS. SUMMARY: Examine 15 years of SST data from the Pacific Marine Environmental Laboratory. Create and analyze average SST maps to identify El Nino and La Nina events.
Smith, David; Youngman, Betsy
Relationship Between the Clouds and the Earth's Radiant Energy System (CERES) Measurements and Surface Temperatures of Selected Ocean Regions
NASA Technical Reports Server (NTRS)
Clear sky longwave radiances and fluxes are compared with the sea surface temperatures for three oceanic regions: Atlantic, Indian, and Pacific. The Clouds and the Earth's Radiant Energy System (CERES) measurements were obtained by the three thermistor bolometers: total channel which measures the radiation arising from the earth-atmosphere system between 0.3 - greater than 100 micrometers; the window channel which measures the radiation from 8-12 micrometers; and the shortwave channel which measures the reflected energy from 0.3 - less than 5.0 micrometers. These instruments have demonstrated measurement precisions of approximately 0.3% on the International Temperature Scale of 1990 (ITS-90) between ground and on-orbit sensor calibrations. In this work we have used eight months of clear sky earth-nadir-view radiance data starting from January 1998 through August 1998. We have found a very strong correlation of 0.97 between the CERES window channel's weekly averaged unfiltered spectral radiance values at satellite altitude (350 km) and the corresponding weekly averaged sea surface temperature (SST) data covering all the oceanic regions. Such correlation can be used in predicting the sea surface temperatures using the present CERES Terra's window channel radiances at satellite altitude very easily.
Pandey, Dhirendra, K.; Lee, Robert B., III; Brown, Shannon B.; Paden, Jack; Spence, Peter L.; Thomas, Susan; Wilson, Robert S.; Al-Hajjah, Aiman
Modeling Hot and Cold Planets: Activity C Approximating the Average Surface Temperature of the Earth
NSDL National Science Digital Library
In this activity, students explore the importance of adequate sampling strategies when conducting a scientific investigation. They are tasked with determining the average temperature of the Earth, using data sets easily found on the Internet, and determine the kind and size of sample necessary to calculate a representative average. The resource includes a student data sheet and an authentic assessment for the module, where students discuss the establishment of a habitation site on Mars. This is Activity C in module 2, titled "Modeling Hot and Cold Planets," of the resource, Earth Climate Course: What Determines a Planet's Climate? The course aims to help students to develop an understanding of our environment as a system of human and natural processes that result in changes that occur over various space and time scales.
The inner core and the surface heat flow as clues to estimating the initial temperature of the Earth's core
NASA Astrophysics Data System (ADS)
This paper attempts to estimate the temperature of the deep interior of the early Earth. The initial temperature cannot be too high or too low in order to realize the present-day thermal state, such as the surface heat flow and the inner core size. Two constraints have been placed: (1) The age of the core is 4.4�10 9 years, comprised of periods of liquid phase and liquid-solid phase, (2) the present-day heat flow is 4.4�10 13 W at the Earth's surface. Global energy balance equations for a parameterized convection model are solved to obtain the initial temperature that satisfies the constraints. The model includes the effect of the inner core growth as well as partial layering of mantle convection. The effect of the partial layering is taken into the model by assuming enhanced thermal conduction across the mid-mantle transition zone, with conductivity ?K times as high as the background. The parameter ? in the Nusselt-Rayleigh number relationship is also employed as an adjustable parameter. Our preferred model for the mantle with a homogeneous distribution of radioactive elements gives 4200�80 K as the initial temperature at the core mantle boundary with parameters ?K=3, ?=0.1, based on Boehler's model of melting temperature of the core. ?K can be related to partial layering parameter representing the mass flux across the transition zone. ?K=3 implies about 70% mass flux, in comparison with whole mantle convection, flowing across the transition zone. The initial temperature 4200 K leads to the present-day temperature of 3820 K at the core mantle boundary. Temperature of the thermal boundary layer at the base of the mantle has been estimated to be 2940 K at its the top surface, producing 880 K decrease across the boundary with a thickness of 180 km. Total heat flow from the core to the mantle is obtained to be 7.5�10 12 W, while it was 8.0�10 12 W when the inner core began to solidify 1.9�10 9 years ago.
Yukutake, Takesi
Effects of temperature-dependent molecular absorption coefficients on the thermal infrared remote sensing of the earth surface
NASA Technical Reports Server (NTRS)
The effect of temperature-dependent molecular absorption coefficients on thermal infrared spectral signatures measured from satellite sensors is investigated by comparing results from the atmospheric transmission and radiance codes LOWTRAN and MODTRAN and the accurate multiple scattering radiative transfer model ATRAD for different atmospheric profiles. The sensors considered include the operational NOAA AVHRR and two research instruments planned for NASA's Earth Observing System (EOS): MODIS-N (Moderate Resolution Imaging Spectrometer-Nadir-Mode) and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer). The difference in band transmittance is as large as 6 percent for some thermal bands within atmospheric windows and more than 30 percent near the edges of these atmospheric windows. The effect of temperature-dependent molecular absorption coefficients on satellite measurements of sea-surface temperature can exceed 0.6 K. Quantitative comparison and factor analysis indicate that more accurate measurements of molecular absorption coefficients and better radiative transfer simulation methods are needed to achieve SST accuracy of 0.3 K, as required for global numerical models of climate, and to develop land-surface temperature algorithms at the 1-K accuracy level.
Wan, Zhengming; Dozier, Jeff
The Carbon Dioxide Concentration in Earth�s atmosphere and Its Possible Influence on the Temperature at the Surface - as discussed in Sweden in 1894-96
NASA Astrophysics Data System (ADS)
On November 15, 1894, Arvid H�gbom, geologist, presented a paper at a meeting of the Swedish Chemical Society (�Kemistsamfundet) in Uppsala. His title: �On the probability of secular changes in the atmosphere�s carbonic acid concentration�. The possibility that changes in the carbon dioxide concentration would produce changes in the surface temperature came up in the discussion after the talk. In the audience was Svante Arrhenius. In early 1896, at another meeting of Kemistsamfundet, Arrhenius followed up on this with a paper �The influence of the carbonic acid concentration on the temperature at the surface of the Earth�. Both papers were published in Svensk Kemisk Tidscrift - Vol. 6 and Vol. 7 - as part of the minutes of the corresponding meetings. Arrhenius continued to pursue the idea, presenting and writing about it outside of Sweden. Most histories credit Arrhenius�s work as the first on global warming, although some mention H�gbom�s prior report. H�gbom�s paper has never been translated from the Swedish, at least not so far as I have been able to discover. I will present a translation and review of H�gbom�s elegant paper and Arrhenius's initial response.
Willson, Lee Anne M.
Long-range memory in Earth surface temperatures: spatial scale dependence and land-sea differences
NASA Astrophysics Data System (ADS)
We present a study of how the long-range memory in temperature time series on scales from months to decades varies between land and sea, and with different degrees of spatial averaging. Earlier analyses suggest that sea temperatures are more persistent than land temperatures, and that global temperatures are more persistent than regional temperatures. As a measure of the long-range memory we estimate the Hurst exponent H by parametric as well as non-parametric methods, and by performing spatial averaging of global gridded temperatures we make a systematic investigation of how the Hurst exponent varies on different spatial scales and between ocean/coastal and continental interior data records. Increasing spatial scale from local records up to the global scale implies that for these data aggregation of relatively weakly persistent records produce records with strong long-range persistence (H?1). We propose some statistical models that may give rise to this phenomenon and discuss their physical relevance.
Fredriksen, Hege-Beate; Rypdal, Kristoffer; Rypdal, Martin
NSDL National Science Digital Library
Explore the relationship between sea surface temperature (SST) and Earth's climate system, and consider the effects that changes in SST are having in the Arctic and beyond in this interactive activity produced for Teachers' Domain featuring data and visualization from NOAA.
Foundation, Wgbh E.
Our contaminated atmosphere: The danger of climate change, phases 1 and 2. [effect of atmospheric particulate matter on surface temperature and earth's radiation budget
NASA Technical Reports Server (NTRS)
The effects of increased concentrations of atmospheric particulate matter on average surface temperature and on the components of the earth's radiation budget are studied. An atmospheric model which couples particulate loading to surface temperature and to changes in the earth's radiation budget was used. A determination of the feasibility of using satellites to monitor the effect of increased atmospheric particulate concentrations is performed. It was found that: (1) a change in man-made particulate loading of a factor of 4 is sufficient to initiate an ice age; (2) variations in the global and hemispheric weighted averages of surface temperature, reflected radiant fluz and emitted radiant flux are nonlinear functions of particulate loading; and (3) a black satellite sphere meets the requirement of night time measurement sensitivity, but not the required day time sensitivity. A nonblack, spherical radiometer whose external optical properties are sensitive to either the reflected radiant fluz or the emitted radiant flux meets the observational sensitivity requirements.
Cimorelli, A. J.; House, F. B.
Rare Earth Optical Temperature Sensor
NASA Technical Reports Server (NTRS)
A new optical temperature sensor suitable for high temperatures (greater than 1700 K) and harsh environments is introduced. The key component of the sensor is the rare earth material contained at the end of a sensor that is in contact with the sample being measured. The measured narrow wavelength band emission from the rare earth is used to deduce the sample temperature. A simplified relation between the temperature and measured radiation was verified experimentally. The upper temperature limit of the sensor is determined by material limits to be approximately 2000 C. The lower limit, determined by the minimum detectable radiation, is found to be approximately 700 K. At high temperatures 1 K resolution is predicted. Also, millisecond response times are calculated.
Chubb, Donald L.; Wolford, David S.
Surface Temperature Data Analysis
NASA Technical Reports Server (NTRS)
Small global mean temperature changes may have significant to disastrous consequences for the Earth's climate if they persist for an extended period. Obtaining global means from local weather reports is hampered by the uneven spatial distribution of the reliably reporting weather stations. Methods had to be developed that minimize as far as possible the impact of that situation. This software is a method of combining temperature data of individual stations to obtain a global mean trend, overcoming/estimating the uncertainty introduced by the spatial and temporal gaps in the available data. Useful estimates were obtained by the introduction of a special grid, subdividing the Earth's surface into 8,000 equal-area boxes, using the existing data to create virtual stations at the center of each of these boxes, and combining temperature anomalies (after assessing the radius of high correlation) rather than temperatures.
Hansen, James; Ruedy, Reto
NSDL National Science Digital Library
This section of the Windows to the Universe web site provides information and images about Earth including detailed information about Earth's interior layers, Earth's surface, and plate tectonics. Windows to the Universe is a user-friendly learning system pertaining to the Earth and Space sciences. The objective of this project is to develop an innovative and engaging web site that spans the Earth and Space sciences and includes a rich array of documents, including images, movies, animations, and data sets that explore the Earth and Space sciences and the historical and cultural ties between science, exploration and the human experience. Links at the top of each page allow users to navigate between beginner, intermediate and advanced levels.
Johnson, Roberta
Surface temperatures at the nearside of the Moon as a record of the radiation budget of Earth�s climate system
Understanding the balance between incoming radiation from the Sun and outgoing radiation from Earth is of critical importance in the study of climate change on Earth. As the only natural satellite of Earth, the Moon is a unique platform for the study of the disk-wide radiation budget of Earth. There are no complications from atmosphere, hydrosphere, or biosphere on the
Shaopeng Huang
Arctic Land-Surface Temperatures Increasing From 2000 Through 2012 Derived By MODIS Sensors on NASA Earth Observing Satellites
NASA Astrophysics Data System (ADS)
Heating of land surfaces by solar irradiance is a fundamental parameter of environment and climate. Across the Arctic changes in active layer, melting of glaciers and ground ice, thawing of permafrost and sequestration changes of carbon storage are driven in part by variations of land surface heat absorption and conduction. In permafrost regions taliks are important for water movement and heat advection into the ground. We investigate land-surface temperature changes and regional variations derived by the MODIS sensors (Terra EOS-AM and Aqua EOS-PM) at the spatial and temporal resolutions of 1-km and daily across the Arctic from March 2000 through July 2012. Since 2000 the number of days with daytime Land-surface temperatures above 0 degree C increases by fourteen. On average Arctic land-surface daytime temperature increase is 2.1 +/- 0.2 degree C with a P-Value of 0.01 and R-Square of 0.97. Regional increases are 1.7 +/- 0.3 degree C for Northern Eurasia, 1.9 +/- 0.2 degree C for Northern Far East Russia-Western North America and 2.5 +/- 0.3 degree C for Eastern North America-Greenland-Northwestern Europe with significant P-Value and R-Square. Coordination of terrestrial measurement network stations with satellite-based measurement systems is required for assessment, evaluation and prognoses of impacts of land-surface temperature changes to the Arctic environment, communities and infrastructures.
Muskett, R. R.
Desorption of radon at the Earth's surface
Measurements of the sorption coefficient for trace amounts of radon in carrier air were made for a variety of porous materials common at the Earth's surface. The technique used was specific for sorption, so some of the ambiguities in previous studies were avoided. Generally, sorption coefficients decrease significantly with increasing moisture and temperature. Model calculations were carried out to relate
S. D. Schery; S. Whittlestone
Earth's Changing Surface: Unit Outlines
NSDL National Science Digital Library
This article assembles free resources from the Earth's Changing Surface issue of the Beyond Penguins and Polar Bears cyberzine into a unit outline based on the 5E learning cycle framework. Outlines are provided for Grades K-2 and 3-5.
Fries-Gaither, Jessica
Temperature, Pressure, and the Earth
NSDL National Science Digital Library
This is a lesson where learners explore the effects of pressure on temperature and states of matter and use this information to infer the conditions of the interior of the Earth. The lesson models scientific inquiry using the 5E instructional model and includes teacher notes, prerequisite concepts, common misconceptions, student journal and reading. This is lesson 2 in the Astro-Venture Geology Training Unit that was developed to increase students' awareness of and interest in astrobiology and the many career opportunities that utilize science, math and technology skills. The lessons are designed for educators to use with the Astro-Venture multimedia modules.
NSDL National Science Digital Library
This illustration of Earth's sea surface temperature was obtained from two weeks of infrared observations by the Advanced Very High Resolution Radiometer (AVHRR), an instrument on board NOAA-7, during July 1984. Temperatures are color coded with red being warmest and decreasing through oranges, yellows, greens, and blues. The caption provides a brief description of the features seen in the image.
NSDL National Science Digital Library
Users can search for and view sea surface temperature imagery. They may choose from the latest image, or browse archived imagery that dates back approximately two weeks. Links to other sea surface temperature datasets are included.
Dropping Two Balls Near the Earth's Surface
NSDL National Science Digital Library
The representation depicts two balls being dropped near the Earth's surface in an interactive simulation. The user can control the initial horizontal speed of one ball and observe the path and acceleration of both balls as they fall and hit the Earth's surface at the same time.
Harrison, David M.
NSDL National Science Digital Library
The purpose of this activity is to measure surface temperature with a handheld Infrared Thermometer (IRT). The instrument is pointed at the ground to take surface temperature readings. Intended outcomes are that students will learn to use an infrared thermometer, and understand how different surfaces radiate energy. Supporting background materials for both student and teacher are included.
The GLOBE Program, UCAR (University Corporation for Atmospheric Research)
How Do Map Projections Distort Earth's Surface?
NSDL National Science Digital Library
This site, part of Exploring Earth Investigation by McDougal Littell and TERC, examines how map projects distort Earth's surface. The investigations "were designed to build students' knowledge of Earth Science concepts�and to raise student awareness of Earth as a system of interconnected components and processes." On the site, visitors will find information on representing the spherical Earth on a flat map, the different common projections used, and how to measure the properties of the projections. Many sections contain interactive features and questions which allow students to investigate and understand the ways that flattening the Earth creates problems with maps and what cartographers have done to minimize the distortion. This is an excellent site for any Earth Science classroom as an introductory lecture or out-of-class exploration.
NSDL National Science Digital Library
This site, NASA GISS Surface Temperature (GISTEMP) analysis, provides a measure of the changing global surface temperature with monthly resolution for the period since 1880, when a reasonably global distribution of meteorological stations was established. Data for individual stations, aggregate data, graphs, charts, maps, and animations are included, and tables of data are also linked to the site.
Goddard Institute for Space Studies (GISS); Nasa
Tilts in the earth's surface caused by atmospheric pressure variations
The drift detected by tide-recording tiltmeters is thought to result from nonperiodic atmospheric pressure and temperature variations which produce elastic deformations that are transmitted downwards from the surface. These deformations can be detected in distant areas of the earth's surface. Examples are presented which show good correlation between the drift detected by tiltmeters and daily atmospheric pressure variations. A lag
K. Z. Kartvelishvili; V. I. Mirianashvili
Surface Reflectance and Ocean Temperature
NASA Technical Reports Server (NTRS)
MODIS's 36 spectral bands provide scientists the chance to study many of Earth's terrestrial and oceanic characteristics with a single instrument, for example, Sea Surface Temperature (SST) and Land Surface Reflectance (LSR). This image was made from data collected during the month of May 2001. The LSR portion of the image is made from data collected at three wavelengths: 645 nm (red), 555 nm (green), and 469 nm (blue). This combination is similar to what our eyes would see. Combined with the land surface data are MODIS's measurements of SST in May, using detectors that capture thermal radiation at 4.0 um, a design innovation that improves measurements in moist areas, such as the tropics, where persistent clouds often interfere with satellite measurements of SST. Large-scale temperature patterns are apparent, such as the Gulf Stream off the east coast of the United States, and the Kuroshio Circulation southeast of Japan
Initiation of clement surface conditions on the earliest Earth.
In the beginning the surface of the Earth was extremely hot, because the Earth as we know it is the product of a collision between two planets, a collision that also created the Moon. Most of the heat within the very young Earth was lost quickly to space while the surface was still quite hot. As it cooled, the Earth's surface passed monotonically through every temperature regime between silicate vapor to liquid water and perhaps even to ice, eventually reaching an equilibrium with sunlight. Inevitably the surface passed through a time when the temperature was around 100 degrees C at which modern thermophile organisms live. How long this warm epoch lasted depends on how long a thick greenhouse atmosphere can be maintained by heat flow from the Earth's interior, either directly as a supplement to insolation, or indirectly through its influence on the nascent carbonate cycle. In both cases, the duration of the warm epoch would have been controlled by processes within the Earth's interior where buffering by surface conditions played little part. A potentially evolutionarily significant warm period of between 10(5) and 10(7) years seems likely, which nonetheless was brief compared to the vast expanse of geological time. PMID:11259665
Sleep, N H; Zahnle, K; Neuhoff, P S
Ocean Currents and Sea Surface Temperature
NSDL National Science Digital Library
Students will make predictions by linking current scientific satellite data to concerns about global climate change. Using maps of sea surface temperature (SST) and ocean surface winds, students will learn how differential heating of Earth results in circulation patterns in the atmosphere and oceans that globally distribute the heat. Students will learn the relationship between the rotation of Earth and the circular motions of ocean currents and air in pressure centers.
We update the Goddard Institute for Space Studies (GISS) analysis of global surface temperature change, compare alternative analyses, and address questions about perception and reality of global warming. Satellite-observed night lights are used to identify measurement stations located in extreme darkness and adjust temperature trends of urban and periurban stations for nonclimatic factors, verifying that urban effects on analyzed global
J. Hansen; R. Ruedy; M. Sato; K. Lo
Surface Temperature: Contouring Isotherms
NSDL National Science Digital Library
This interactive feature shows how an isothermal map of surface temperature is drawn. Students can select an individual contour value and watch as a virtual 'pencil' correctly places the line with respect to temperature values on the map. The animation also permits the user to color the spaces between the contour lines on the map.
Editor's Roundtable: Sculpting the Earth's surface
NSDL National Science Digital Library
Our students need to know about the structure of the Earth and about the geological processes that shape its surface--both the long-term and the everyday processes, the abrupt shifts of faults, the sustained movements of tectonic plates, and slow uplift of mountains. Therefore, this issue of Science Scope focuses on Earth processes. Use this collection of activities to awaken your students to the factors that shape the continents and the hills, valleys, rivers, fields, lakes, and oceans around them.
Liftig, Inez
NiO-Alkaline Earth Oxide Catalysts for Oxidative Methane-to-Syngas Conversion: Influence of Alkaline Earth Oxide on the Surface Properties and Temperature-Programmed Reduction\\/Reaction by H 2and Methane
Temperature-programmed reaction of pure methane from 100�900�C with NiO-MgO, NiO-CaO, NiO-SrO, and NiO-mixed alkaline earth oxides (viz., MgO-CaO, MgO-SrO, MgO-BaO, CaO-SrO, CaO-BaO, and SrO-BaO) with Ni\\/alkaline earth element(s) ratio of 1.0 (calcined at 930�C for 4 h) has been studied. Temperature-programmed reduction of these catalysts and NiO-MgO with different Ni\\/Mg ratios by H2from 100�C to 900�C has also been thoroughly
V. R. Choudhary; A. M. Rajput; A. S. Mamman
Global Surface Temperature Change
NASA Astrophysics Data System (ADS)
We update the Goddard Institute for Space Studies (GISS) analysis of global surface temperature change, compare alternative analyses, and address questions about perception and reality of global warming. Satellite-observed night lights are used to identify measurement stations located in extreme darkness and adjust temperature trends of urban and periurban stations for nonclimatic factors, verifying that urban effects on analyzed global change are small. Because the GISS analysis combines available sea surface temperature records with meteorological station measurements, we test alternative choices for the ocean data, showing that global temperature change is sensitive to estimated temperature change in polar regions where observations are limited. We use simple 12 month (and n � 12) running means to improve the information content in our temperature graphs. Contrary to a popular misconception, the rate of warming has not declined. Global temperature is rising as fast in the past decade as in the prior 2 decades, despite year-to-year fluctuations associated with the El Ni�o-La Ni�a cycle of tropical ocean temperature. Record high global 12 month running mean temperature for the period with instrumental data was reached in 2010.
Hansen, J.; Ruedy, R.; Sato, M.; Lo, K.
Influence of Land-Surface Evapotranspiration on the Earth's Climate
Calculations with a numerical model of the atmosphere show that the global fields of rainfall, temperature, and motion strongly depend on the landsurface evapotranspiration. This confirms the long-held idea that the surface vegetation, which produces the evapotransporation, is an important factor in the earth's climate.
J. Shukla; Y. Mintz
National Center for Earth-surface Dynamics
NSDL National Science Digital Library
NCED (the National Center for Earth-surface Dynamics) is a National Science Foundation Science and Technology Center. We began operation in August, 2002; we're headquartered at the St. Anthony Falls Laboratory at the University of Minnesota. Our purpose is to catalyze development of an integrated, predictive science of the processes shaping the surface of the Earth in order to transform management of ecosystems, resources, and land use. In concert with our integrative research efforts, we strive to bring our methods and results to students, the public, and practitioners in agencies and industry.
Dynamics, National C.
Global Surface Temperature Change
We update the Goddard Institute for Space Studies (GISS) analysis of global surface temperature change, compare alternative analyses, and address questions about perception and reality of global warming. Satellite-observed nightlights are used to identify measurement stations located in extreme darkness and adjust temperature trends of urban and peri-urban stations for non-climatic factors, verifying that urban effects on analyzed global change
J. Hansen; R. Ruedy; M. Sato
Deformation of the Earths Surface by Local Mass Loading
NASA Astrophysics Data System (ADS)
The mass of big building cause a deformation of the Earth crust up to long distance from area of realization. The elastic and rheological effects are modelled as viscoelastic and plastic. In both cases exists new factor-time. More deeply knowledge of mechanical properties of materials and modern computer equipment allow construct very precise model reaction of the Earth surface on loading in time. Geodesists and geophysicists need to know this laws of surface deformation and theirs time evolution for geodetic nets design, for analysis of repeated measurements or analysis time series. The poster contents the mathematical modelling of the Earth elastic surface deformation caused by symmetric loading of its boundary, time evolution of vertical displacements and local deformation caused temperature effects.
Mojzes, Marcel; Kollar, Pavol; Valko, Milos
Adsorption of polyvinylalcohol onto Fuller's earth surfaces
The adsorption of polyvinyl alcohol (PVA) onto Fuller's earth surfaces has been studied at fixed pH (4.8) and ionic strength of the medium. The adsorption isotherm obtained resembles with LIII type of isotherm, which indicates that multilayer formation of polymer chains begins after a certain time period when the monolayer formation is complete. The study of concentration effect and kinetics
A. K. Bajpai; N. Vishwakarma
A wide-field color-coded infra-red imaging device was applied to the measurement of i) the temperature profile across the ocular surface and ii) the temporal stability of central corneal temperature, on 21 subjects. The thermographs showed a pattern of ellipsoidal isotherms (major axis horizontal) approximately concentric about a temperature apex (coldest point) which was slightly inferior to the geometric center of the cornea (GCC). The GCC had a mean temperature (+/- SD) of 34.3 +/- 0.7 degrees C (range 32.8 to 35.4 degrees C). Temperature increased towards the periphery of the cornea with the limbus being 0.45 degrees C warmer than the GCC (p less than 0.0001). Following a blink, the GCC cooled at a mean (+/- SD) rate of 0.033 +/- 0.024 degrees C/s (p less than 0.0001) over the first 15s. Subjects whose corneas cooled more slowly following a blink demonstrated a greater capacity to avoid blinking for a prolonged period (p less than 0.05). This improved method of measuring ocular surface temperature has important applications in modeling corneal physiology and pathology. PMID:2791634
Efron, N; Young, G; Brennan, N A
Pliocene Sea Surface Temperature Variability
Anthropogenic greenhouse gas emissions and modification of land surfaces are expected to cause the earth's climate to warm. However the amount and details of the warming are still highly uncertain. Identifying and predicting human related changes must take into account natural climate variability and the complex interactions of the different components of the Earth's climate system. The USGS PRISM (Pliocene
H. J. Dowsett; M. A. Chandler
NSDL National Science Digital Library
This NASA (National Aeronautics and Space Administration) planet profile provides data and images of the planet Earth. These data include planet size, orbit facts, distance from the Sun, rotation and revolution times, temperature, atmospheric composition, density, surface materials and albedo. Images with descriptions show Earth features such as the Ross Ice Shelf in Antarctica, Simpson Desert in Australia, Mt. Etna in Sicily, the Cassiar Mountains in Canada, the Strait of Gibraltar, Mississippi River, Grand Canyon, Wadi Kufra Oasis in Libya, and Moon images such as Hadley Rille, Plum Crater, massifs and Moon rocks. These images were taken with the Galileo Spacecraft and by the Apollo missions.
The Earth surface slide movement at Soledad
NASA Astrophysics Data System (ADS)
The Earth surface slide movement at Soledad is a mountain-slide type of movement. Estimations of the thickness of the layer which is moving range between 10 and 100 m. There is no proof that the movement is water induced, but it could be influenced by the water household. The slope of the slide area is H: D = 1: 2. The height difference in the moving area studied, according to this paper, is 1 km. The actual rate of movement is about 12 cm/yr.
Moreno, A.
Did surface temperatures constrain microbial evolution?
NASA Technical Reports Server (NTRS)
The proposition that glaciation may not have occurred before the Cenozoic--albeit not yet a consensus position--nevertheless raises for reconsideration the surface temperature history of the earth. Glacial episodes, from the Huronian (2.3 billion years ago; BYA) through the late Paleozoic (320 to 250 million years ago; MYA) have been critical constraints on estimation of the upper bounds of temperature (Crowley 1983, Kasting and Toon 1989). Once removed, few if any constraints on the upper temperature limit other than life remain. Walker (1982) recognized that life provides an upper limit to temperature in the Precambrian. We propose a more radical concept: the upper temperature limit for viable growth of a given microbial group corresponds to the actual surface temperature at the time of the group's first appearance. In particular, we propose here that two major evolutionary developments--the emergence of cyanobacteria and aerobic eukaryotes--can be used to determine surface temperature in the Precambrian, and that only subsequent cooling mediated by higher plants and then angiosperms permitted what may possibly be the earth's first glaciation in the late Cenozoic.
Schwartzman, D.; McMenamin, M.; Volk, T.
Stability of hydrocarbons at deep Earth pressures and temperatures
Determining the thermochemical properties of hydrocarbons (HCs) at high pressure and temperature is a key step toward understanding carbon reservoirs and fluxes in the deep Earth. The stability of carbon-hydrogen systems at depths greater than a few thousand meters is poorly understood and the extent of abiogenic HCs in the Earth mantle remains controversial. We report ab initio molecular dynamics simulations and free energy calculations aimed at investigating the formation of higher HCs from dissociation of pure methane, and in the presence of carbon surfaces and transition metals, for pressures of 2 to 30�GPa and temperatures of 800 to 4,000�K. We show that for T?2,000�K and P?4�GPa HCs higher than methane are energetically favored. Our results indicate that higher HCs become more stable between 1,000 and 2,000�K and P?4�GPa. The interaction of methane with a transition metal facilitates the formation of these HCs in a range of temperature where otherwise pure methane would be metastable. Our results provide a unified interpretation of several recent experiments and a detailed microscopic model of methane dissociation and polymerization at high pressure and temperature.
Spanu, Leonardo; Donadio, Davide; Hohl, Detlef; Schwegler, Eric; Galli, Giulia
Surface Temperature Estimation Over Land Using Satellite Microwave Radiometry
NASA Technical Reports Server (NTRS)
Surface temperature is an important parameter of the physical processes that govern the fluxes of energy and water at the biosphere-atmosphere interface. The energy and water fluxes have major influences on the Earth's weather and climate.
Njoku, E. G.
Accelerated Multiscale Analysis on the Earth's Surface
NASA Astrophysics Data System (ADS)
By the use of an underlying Runge sphere harmonic scaling functions and wavelets can be constructed on regular surfaces such as the surface of the Earth. They allow a space-frequency decomposition of geopotentials on the surface. Moreover, due to their localizing properties regional modeling or the improvement of a global model is possible. The acceleration of the convolution by the fast multipole method is possible for certain types of harmonic scaling functions and wavelets. The main idea of the fast multipole algorithm consists of a hierarchical decomposition of the computational domain into cubes and a kernel approximation for the more distant points. The kernel evaluation is performed directly only for points in neighboring cubes on the finest level. The contributions of the other points are transferred into a set of coefficients. The kernel approximation is applied on the coarsest possible level using translations of these coefficients. This reduces the numerical effort of the convolution for a prescribed accuracy of the kernel approximation. Multiscale methods are known to possess a tree algorithm that allows the computation of the lower frequency scales from a starting scale that contains the highest frequency parts of the signal. The application of the fast multipole method can accelerate the computation of this starting point as well as the tree algorithm itself. The presentation includes applications to gravitational field modeling.
Gutting, Martin
Surface Temperature Assimilation in Land Surface Models
NASA Technical Reports Server (NTRS)
This paper examines the utilization of surface temperature as a variable to be assimilated in offline land surface hydrological models. Comparisons between the model computed and satellite observed surface temperatures have been carried out. The assimilation of surface temperature is carried out twice a day (corresponding to the AM and PM overpass of the NOAA10) over the Red-Arkansas basin in the Southwestern United States (31 degs 50 sec N - 36 degrees N, 94 degrees 30 seconds W - 104 degrees 3 seconds W) for a period of one year (August 1987 to July 1988). The effect of assimilation is to reduce the difference between the surface soil moisture computed for the precipitation and/or shortwave radiation perturbed case and the unperturbed case compared to no assimilation.
Lakshmi, Venkataraman
Geodiversity of the Earth's surface and environment
NASA Astrophysics Data System (ADS)
Geologic and geographic objects can be successfully systemized based on the mathematical theories of diversity and sets. This can give us a clear understanding of the nomenclature of the Earth's surface: its elements, forms, as well as their combinations and structures. All these surface structural units are closely related to elementary landscapes, or geotops (other elementary locations such as biotops, lythotops, edafotops, hydrotops, climatops, and etc. can also be considered). Both surface structural units and corresponding geotops should be studied on two systematic levels: 1) the morphological one that provides us with the taxonomic (by unit size) and meronomic (by unit complexity) information, and 2) the dynamical one that allows working out various interpretations: geo-flows and their influence on the Earth's surface (including new formation and complete destruction of elements and forms), sustainability of geodiversity, etc. At the present time, the dynamical level is in a process of defining clear criteria and developing relevant classification. The morphological level has in turn three sub-levels: a) relief elements, b) landforms (geomorphosystems), and c) regions (super-geomorphosystems). The entire set of two-dimensional surface elements comprises 52 variants (elementary surfaces) and more than 2,700 three-dimensional geotops. Each of the geotops is characterized by four different exposures: gravitational (hypso- and bathymetric position, steepness, vertical and horizontal curvature), insolational (dip azimuth of the location), circulating (orientation against prevailing flows - frontal, rear or flank position), and anthropogenic ones. The most contrasting geotops are tied to the upper (tops, crests and their adjacent areas) and lower (bottoms, thalwegs and their adjacent areas) relief elements. Slope elements (faces, cliffs, terraces, and feet) serve as the linking areas and determine not the diversity as such but, first of all, commonalities of the territory. The second morphological level - landforms - comprises 145 variants of geomorphosystems. They are classified according to the sign and shape in plan and profile, inner structure presented by vector lines (circle, ellipse, hyperbola, parabola, and lattice figures), outer structure presented by contours (isometric, brachy-, hemi-, bilateral, and linear ones), as well as their determinants and dominants. The determinants (in the number of 18) are the elements - mainly structural lines - that determine the whole landform (ridge, valley, trough, swell, volcanic cone, etc.); elementary surfaces dominating the landform serve as its dominants (37). The third morphological level - geomorphologic regions - reflects geodiversity of a larger scale. It follows to a certain extent the classification on the first, elementary, level but is also supplemented with the analysis of extended symmetry and anisotropy carried out on a geomorphologic map. All abovementioned fundamentals in a much more detailed way can be easily found in the monograph by Alexander Lastochkin "General theory of geosystems" (St. Petersburg, 2011, in Russian) and in the "Geomorphologic Atlas of the Antarctic" (St. Petersburg, 2012 - in Russian; 2013 - in English) produced by the team of authors.
Lastochkin, Alexander; Zhirov, Andrey; Boltramovich, Sergei
HCMM satellite to take earth's temperature
NASA Technical Reports Server (NTRS)
The heat capacity mapping mission (HCMM), a low cost modular spacecraft built for the Applications Explorer Missions (AEM), was designed to allow scientists to determine the feasibility of using day/night thermal infrared remote sensor-derived data to: (1) discriminate various rock types and locate mineral resources; (2) measure and monitor surface soil moisture changes; (3) measure plant canopy temperatures at frequent intervals to determine transpiration of water and plant stress; and (4) measure urban heat islands. The design of the spacecraft (AEM-A), its payload, launch vehicle, orbit, and data collection and processing methods are described. Projects in which the HCMM data will be applied by 12 American and 12 foreign investigators are summarized.
Temperature coefficients of rare earth permanent magnets
A new approach for calculating the temperature coefficients of magnetic parameters is proposed in order to more accurately describe high temperature characteristics of magnetic materials. Using this new approach, the �true� (or instantaneous) temperature coefficient of any magnetic parameter at a specific temperature can be determined and a plot of temperature coefficient vs. temperature can be obtained. This new type
Sam Liu; G. Edward Kuhl
Local Sounding of the Earth Due to Interference of Electromagnetic Waves Near Earth's Surface
The theory of electromagnetic sounding of the earth, based on interference effects in the spatial structure of a pair of coupled waves, propagating along the earth's surface with the same frequency but different wavelengths, is proposed. A hitherto unknown heterogeneous structure of surface impedance, the conductivity being constant, is analysed by means of new exact analytical solutions of Maxwellian equations,
A. B. Shvartsburg; M. A. Zuev
UV 380 nm Reflectivity of the Earth's Surface.
National Technical Information Service (NTIS)
The 380 nm radiance measurements of TOMS (Total Ozone Mapping Spectrometer) have been converted into a global data set of daily (1979 to 1992) Lambert equivalent reflectivities R of the Earth's surface and boundary layer (clouds, aerosols, surface haze, a...
J. R. Herman E. Celarier D. Larko
Global surface temperatures and the atmospheric electrical circuit
To monitor future global temperature trends, it would be extremely useful if parameters nonlinearly related to surface temperature could be found, thereby amplifying any warming signal that may exist. Evidence that global thunderstorm activity is nonlinearly related to diurnal, seasonal and interannual temperature variations is presented. Since global thunderstorm activity is also well correlated with the earth's ionospheric potential, it
Colin Price
Flexible Multiplexed Surface Temperature Sensor
NASA Technical Reports Server (NTRS)
Unitary array of sensors measures temperatures at points distributed over designated area on surface. Useful in measuring surface temperatures of aerodynamic models and thermally controlled objects. Made of combination of integrated-circuit microchips and film circuitry. Temperature-sensing chips scanned at speeds approaching 10 kHz. Operating range minus 40 degrees C to 120 degrees C. Flexibility of array conforms to curved surfaces. Multiplexer eliminates numerous monitoring cables. Control of acquisition and recording of data effected by connecting array to microcomputers via suitable interface circuitry.
Daryabeigi, Kamran; Dillon-Townes, L. A.; Johnson, Preston B.; Ash, Robert L.
Temperature profiles in the earth of importance to deep electrical conductivity models
Deep in the Earth, the electrical conductivity of geological material is extremely dependent on temperature. The knowledge of temperature is thus essential for any interpretation of magnetotelluric data in projecting lithospheric structural models. The measured values of the terrestrial heat flow, radiogenic heat production and thermal conductivity of rocks allow the extrapolation of surface observations to a greater depth and
Vladim�r ?erm�k; Marcela Lastovickov�
Rare Earth Doped High Temperature Ceramic Selective Emitters
NASA Technical Reports Server (NTRS)
As a result of their electron structure, rare earth ions in crystals at high temperature emit radiation in several narrow bands rather than in a continuous blackbody manner. This study develops a spectral emittance model for films of rare earth containing materials. Although there are several possible rare earth doped high temperature materials, this study was confined to rare earth aluminum garnets. Good agreement between experimental and theoretical spectral emittances was found for erbium, thulium and erbium-holmium aluminum garnets. Spectral emittances of these films are sensitive to temperature differences across the film. Emitter efficiency is also a sensitive function of temperature. For thulium aluminum garnet the efficiency is 0.38 at 1700 K but only 0.19 at 1262 K.
Chubb, Donald L.; Pal, AnnaMarie; Patton, Martin O.; Jenkins, Phillip P.
The Temperature of the Earth in 2020
NASA Technical Reports Server (NTRS)
In spite of the confusion in the public discourse about global warming, there is no doubt that the Earth has been warming for the past century. The chemistry of the Earth's atmosphere is complex, and it is sometimes difficult to claim cause-and-effect with certainty. Nevertheless, the evidence seems clear that CO2 and non-CO2 forcings such as methane and air pollution are causally related to this warming trend. Our dependence on fossil fuels make it difficult to expect that massive reductions in CO2 will be feasible in the near-term, however. In this talk I will consider the evidence for global warming, the extent to which we can extrapolate current trends into the future if no changes in global policy are introduced, and those near-term policies that might be realistically introduced to significantly affect those trends.
Hansen, James; Einaudi, Franco (Technical Monitor)
How much have variations in the meridional overturning circulation contributed to sea surface temperature trends since 1850? A study with the EC-Earth global climate model
NASA Astrophysics Data System (ADS)
The surface of the worlds' oceans has been warming since the beginning of industrialisation mainly due to larger atmospheric greenhouse gas concentrations. In addition to that multidecadal SST variations of internal origin exist. Evidence points to the North Atlantic Ocean as exhibiting the strongest multidecadal SST variations and that these variations are connected to the overturning circulation. In this work we investigate the extent to which these internal multidecadal variations have contributed to enhancing or diminishing the trend induced by the external radiative forcing globally and in the North Atlantic. We do so in a model study where we combine the analysis of a long control simulation with constant forcing corresponding to preindustrial conditions and an ensemble of simulations with historical forcing from 1850 until 2005. First we note that global SST trends calculated from the different historical simulations are similar, while there is a large disagreement between the North Atlantic SST trends. Then we analyse the control simulation, where we identify a relationship between SST anomalies and anomalies in the Atlantic Meridional Overturning Circulation (AMOC) for multidecadal and longer time scales. This relationship enables us to extract the AMOC-related SST variability from each individual member of the ensemble of historical simulations and then to calculate the SST trends with the AMOC-related variability excluded. For the global SST trends this causes only a little difference while SST trends with AMOC related variability excluded for the North Atlantic show closer agreement than with the AMOC-related variability included. From this we conclude that AMOC variability contributed significantly to North Atlantic SST trends since the mid 19th century.
Schmith, Torben; Yang, Shuting; Gleeson, Emily; Semmler, Tido
Earth Surface Patterns in 200 Years (Invited)
NASA Astrophysics Data System (ADS)
What kinds of patterns will characterize Earth's surface in 200 years? This question is addressed using a complex systems dynamical framework for distinct levels of description in a hierarchy, in which time scale and spatial extent increase and number of variables decrease with level, and in which levels are connected nonlinearly to each other via self-organization and slaving and linearly to the external environment. Self-organized patterns linking the present to 200 years in the future must be described dynamically on a level with a time scale of centuries. Human-landscape coupling will play a prominent role in the formation of these patterns as population peaks and interactions become nonlinear over these time scales. Three related examples illustrate this approach. First, the response of human-occupied coastlines to rising sea level. Coastlines in wealthy regions develop a spatially varying boom and bust pattern, with response amplified by structures meant to delay the effects of sea level rise. Coastlines in economically disadvantaged regions experience a subdued response, with populations developing a culture of displacement that minimizes human-landscape interactions in a context of scarce resources. Second, the evolution of nation-state borders with degrading ecosystems, declining resource availability and increasing transportation costs. The maintenance of strong borders as selective filtration systems (goods, capital and people) is based on a cost-benefit analysis in which the economic benefits accruing from long distance, globalized resource exploitation are weighed against policing and infrastructure costs. As costs rise above benefits, borders fragment, with a transition to local barriers and conflicts, and mobile peoples moving to resources. Third, trends in urbanization and development of megacities under economic and environmental stress. The pattern of rapid growth of megacities through inward migration, with displaced people occupying high-risk urban landscapes such as flood plains or steep slopes and existing on the margins of the formal economic system, switches to outmigration as precarious slum dwellers respond to human-induced natural disasters, crumbling infrastructure and economic decline. Inefficient foraging along outward migration pathways from the urban center drives positive feedbacks that propel a radiating pattern and eventually lead to dispersal. These anticipated patterns represent a fragmentation of economic and power concentrations and networks, and localization of the presently globalized coupled human-landscape system. Long-time-scale models illustrating the fragmentation process and prospects for model testing will be discussed. Supported by the Geomorphology and Land Use Dynamics Program of the US National Science Foundation.
Werner, B.
Mass Loads, Surface Deformation, and the Earth's Rotation
A fluid, mobile atmosphere and oceans surrounds the solid Earth and upon its land surface lies a continually changing global distribution of ice, snow, and ground water. The changing distribution of mass associated with the motion of these surficial fluids changes the load on the solid Earth, thereby causing its shape to change. It has recently been demonstrated that large-scale
R. S. Gross; G. Blewitt; P. J. Clarke; D. A. Lavallee
Precision levels and measurements of tilts of the earth's surface
Measurements of earth-surface tilts during the Tolbachik, Kamchatka volcano eruption are interpreted as being due to displacements of vast masses of the earth's matter. The design of a tiltmeter employing precision cylindrical levels as sensors is described. The properties of levels as a capillary system are discussed, and the sensitivity threshold and instrument error of the tiltmeter are evaluated. Results
Iu. S. Dobrokhotov
Mission to Earth: LANDSAT Views the World. [Color imagery of the earth's surface
NASA Technical Reports Server (NTRS)
The LANDSAT program and system is described. The entire global land surface of Earth is visualized in 400 color plates at a scale and resolution that specify natural land cultural features in man's familiar environments. A glossary is included.
Short, N. M.; Lowman, P. D., Jr.; Freden, S. C.; Finch, W. A., Jr.
Decadal predictability of tropical basin average and global average sea surface temperatures in CMIP5 experiments with the HadCM3, GFDL-CM2.1, NCAR-CCSM4, and MIROC5 global Earth System Models
NASA Astrophysics Data System (ADS)
This paper describes initial results from a broadscale study to assess decadal climate hindcast skills of the HadCM3, GFDL-CM2.1, NCAR-CCSM4, and MIROC5 global Earth System Models (ESMs) in experiments conducted under the Coupled Model Intercomparison Project 5. Analyses of decadal hindcast and simulation experiments using historical aerosol optical depths show statistically significant decadal predictability skill of global average and tropical sea surface temperature (SST) anomalies during 1961-2010. The skill, however, varies by averaging region and decade. It was also found that volcanic eruptions influence SSTs and are one of the sources of decadal SST hindcast skill. In the actual climate system, however, volcanic eruptions themselves are not predictable, and therefore, their effects on the climate system can only be predicted after eruptions. In the four ESMs utilized in this study, decadal hindcast skills of SST anomalies over ocean basin size averaging regions generally improve due to model initialization with observed data.
Mehta, Vikram M.; Wang, Hui; Mendoza, Katherin
Middle Pliocene sea surface temperatures: a global reconstruction
Identification and analyses of Pliocene marine microfossils from 64 globally distributed stratigraphic sequences have been used to produce a middle Pliocene sea surface temperature reconstruction of the Earth. This reconstruction shows little or no change from current conditions in low latitude regions and significant warming of the ocean surface at mid and higher latitudes of both hemispheres. This pattern of
Harry Dowsett; John Barron; Richard Poore
Estimation of Surface Air Temperature from MODIS High Resolution Land Surface Temperature over Northern China
NASA Astrophysics Data System (ADS)
Surface air temperature is a critical variable to describe energy and water cycle of the Earth-atmosphere system and is a key input element for hydrology and land surface models. It is a very important variable in agriculture application and climate change studies. Traditionally, surface air temperatures are obtained from meteorology stations at 2 meter above ground. In general, meteorology stations are distributed sparsely that is not enough for higher resolution model. Recent studies have shown that surface air minimum/maximum temperatures estimated from MODIS Land Surface Temperature (LST) are statistical meaningful in some regions. In this study, we have examined statistical relationship between surface air temperatures and MODIS LST over the Northern China at selected locations. Results indicate that the statistical significance of the estimations depends on the surface type and conditions. As part of the Monsoon Asia Integrated Regional Study (MAIRS) project, NASA GES DISC has processed standard 8-day 1km MODIS product by mosaicing and re-projecting 10x10 degree tiled data files (MOD11A2 and MYD11A2) over the entire monsoon Asia region (60-150E, 0-60N) and made the data accessible through the online visualization and analysis system, Giovanni.
Shen, S.; Leptoukh, G. G.; Gerasimov, I. V.
Intercomparison of the seasonal cycle of Titan's and Earth's surface climatology
NASA Astrophysics Data System (ADS)
The characteristics of the seasonal cycle of Titan's surface temperature, surface pressure and surface wind and their implication for weather are compared with the terrestrial counterpart. The surface climatology of Titan predicted by a GCM and partly observed by Cassini is presented side by side with the well-known Earth's climatology. Even though the surface temperature varies only by a few K in the course of a Titan year, the seasonality of Titan's surface climate is partly more pronounced than on Earth in a qualitative sense. The seasonal forcing can completely reverse the global circulation and precipitation pattern on almost entire Titan in a monsoon-like fashion. This high sensitivity of Titan's climate to small seasonal temperature variations can be mainly ascribed to Titan's slow rotation.
Tokano, T.
Earthing: Health Implications of Reconnecting the Human Body to the Earth's Surface Electrons
Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits�including better sleep and reduced pain�from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance.
Chevalier, Gaetan; Sinatra, Stephen T.; Oschman, James L.; Sokal, Karol; Sokal, Pawel
Earthing: health implications of reconnecting the human body to the Earth's surface electrons.
Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding) refers to the discovery of benefits-including better sleep and reduced pain-from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance. PMID:22291721
Chevalier, Ga�tan; Sinatra, Stephen T; Oschman, James L; Sokal, Karol; Sokal, Pawel
Valence state at the surface of rare-earth metals
The valence state of a rare-earth metal surface is investigated by using general properties of the surface tension of metals. Thereby it is concluded that samarium is likely to have a divalent or partly divalent surface on top of its trivalent bulk phase, which agrees with recent spectroscopic observations. Also californium metal is discussed from this point of view. Finally,
B�rje Johansson
Method for measuring surface temperature
The present invention relates to a method for measuring a surface temperature using is a fluorescent temperature sensor or optical thermometer. The sensor includes a solution of 1,3-bis(1-pyrenyl)propane within a 1-butyl-1-1-methyl pyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid solvent. The 1,3-bis(1-pyrenyl)propane remains unassociated when in the ground state while in solution. When subjected to UV light, an excited state is produced that exists in equilibrium with an excimer. The position of the equilibrium between the two excited states is temperature dependent.
Baker, Gary A. (Los Alamos, NM); Baker, Sheila N. (Los Alamos, NM); McCleskey, T. Mark (Los Alamos, NM)
Indicatrices of the earth's surface reflection from Landsat MSS data.
A method of obtaining an indicatrix or a scattering diagram of the earth's surface is developed. When we regard the earth's surface as a kind of irregular surface, the indicatrix of scattered radiation is a way of effective representation of its surface roughness. The indicatrices of radiation over the sands of a seashore, a downtown area of Tokyo, and some of its suburban areas are obtained from Landsat MSS data. The radiant intensity decreases within the range of 32 degrees to 65 degrees of scattering angles in accordance with the degree of urbanization. Experimental results obtained by a remote sensing simulator are compared with those of Landsat MSS data analysis. PMID:18200248
Okayama, H; Ogura, I
Temperature Dependence of Elastic Constants of Alkaline Earth Oxide Solids
NASA Astrophysics Data System (ADS)
A simple and straightforward theoretical model is developed to investigate the elastic constants of alkaline earth oxide solids under the effect of temperature. The calculation are performed with the help of high temperature equation of state (EOS) derived from Tallon's method based on thermodynamic analysis. The results obtained for these solids are discussed and compared with experimental data under the effect of high temperature. The results are found to be in good agreement with available experimental results
Singh, S. P.
Rare-earth doped optical fibers for temperature sensing
The feasibility of using a variety of rare-earth doped optical fibers for measuring spatially averaged temperatures from ~0 to ~100�C over distances of 10 to 20 m is discussed. Such distributed temperature sensors would be particularly well-suited for building climate control systems and industrial processing applications. The temperature-dependent absorption spectra of 6 MCVD processed fibers containing different concentrations of Nd3+,
Kathryn W. Quoi; Robert A. Lieberman; Leonard G. Cohen; D. Scott Shenk; Jay R. Simpson
MY NASA DATA: Ocean Currents and Sea Surface Temperature
NSDL National Science Digital Library
Satellite data analysis of both ocean currents and sea surface temperatures will allow students to discover the link that exists between them. Students will download data-based maps on which they will determine and then draw directional movement of currents. Then, in both groups and individually, they will discuss the relationship between the currents and sea surface temperatures, answer a set of questions, and predict changes in the appearance of the maps if Earth continues its warming trend. This lesson uses student- and citizen science-friendly microsets of authentic NASA Earth system science data from the MY NASA DATA project. It also includes related links, extensions, and an online glossary.
Using Vegetation, Precipitation, and Surface Temperature to Study Climate Zones
NSDL National Science Digital Library
The type of climate present in a particular location depends on several variables, including surface temperature and annual precipitation. One indicator of a locale' s climate is the vegetation present, a relationship used by the Koeppen system of climate classification. Using a microset of satellite data to investigate vegetation of a particular climate zone, students will identify factors that influence an area's climate. They will explore the relationship between amount of vegetation, precipitation, and surface temperature to study Earth's climate zones.
Aspects Of The Atmospheric Surface Layers On Mars And Earth
The structures of mean flow and turbulence in the atmospheric surface boundary layer have been extensively studied on Earth, and to a far less extent on Mars, where only the Viking missions and the Pathfinder mission have delivered in-situ data. Largely the behaviour of surface-layer turbulence and mean flow on Mars is found to obey the same scaling laws as
S. E. Larsen; H. E. J�rgensen; L. Landberg; J. E. Tillman
Molodensky's theory of the Earth's figure determination using topographic reductions and integration over the Earth's surface.
NASA Astrophysics Data System (ADS)
Molodensky's theory is developed with due regard for the topographic gravity reduction, which can lead to the Earth's mass center displacement from the rotation axis. The possibility of integration over the Earth's surface without transfer to the telluroid is shown. Various measurement data can be used to provide a single solution of this problem, for example land gravity anomalies and results of sea altimetric and gravimetric surveying.
Yurkina, M. I.
NASA's Space Lidar Measurements of Earth and Planetary Surfaces
NASA Technical Reports Server (NTRS)
A lidar instrument on a spacecraft was first used to measure planetary surface height and topography on the Apollo 15 mission to the Moon in 1971, The lidar was based around a flashlamp-pumped ruby laser, and the Apollo 15-17 missions used them to make a few thousand measurements of lunar surface height from orbit. With the advent of diode pumped lasers in the late 1980s, the lifetime, efficiency, resolution and mass of lasers and space lidar all improved dramatically. These advances were utilized in NASA space missions to map the shape and surface topography of Mars with > 600 million measurements, demonstrate initial space measurements of the Earth's topography, and measured the detailed shape of asteroid. NASA's ICESat mission in Earth orbit just completed its polar ice measurement mission with almost 2 billion measurements of the Earth's surface and atmosphere, and demonstrated measurements to Antarctica and Greenland with a height resolution of a few em. Space missions presently in cruise phase and in operation include those to Mercury and a topographic mapping mission of the Moon. Orbital lidar also have been used in experiments to demonstrate laser ranging over planetary distances, including laser pulse transmission from Earth to Mars orbit. Based on the demonstrated value of the measurements, lidar is now the preferred measurement approach for many new scientific space missions. Some missions planned by NASA include a planetary mission to measure the shape and dynamics of Europa, and several Earth orbiting missions to continue monitoring ice sheet heights, measure vegetation heights, assess atmospheric CO2 concentrations, and to map the Earth surface topographic heights with 5 m spatial resolution. This presentation will give an overview of history, ongoing work, and plans for using space lidar for measurements of the surfaces of the Earth and planets.
Abshire, James B.
Magnetic trapping of rare-earth atoms at millikelvin temperatures.
The ability to create quantum degenerate gases has led to the realization of Bose-Einstein condensation of molecules, atom-atom entanglement and the accurate measurement of the Casimir force in atom-surface interactions. With a few exceptions, the achievement of quantum degeneracy relies on evaporative cooling of magnetically trapped atoms to ultracold temperatures. Magnetic traps confine atoms whose electronic magnetic moments are aligned anti-parallel to the magnetic field. This alignment must be preserved during the collisional thermalization of the atomic cloud. Quantum degeneracy has been reached in spherically symmetric, S-state atoms (atoms with zero internal orbital angular momentum). However, collisional relaxation of the atomic magnetic moments of non-S-state atoms (non-spherical atoms with non-zero internal orbital angular momentum) is thought to proceed rapidly. Here we demonstrate magnetic trapping of non-S-state rare-earth atoms, observing a suppression of the interaction anisotropy in collisions. The atoms behave effectively like S-state atoms because their unpaired electrons are shielded by two outer filled electronic shells that are spherically symmetric. Our results are promising for the creation of quantum degenerate gases with non-S-state atoms, and may facilitate the search for time variation of fundamental constants and the development of a quantum computer with highly magnetic atoms. PMID:15372025
Hancox, Cindy I; Doret, S Charles; Hummon, Matthew T; Luo, Linjiao; Doyle, John M
EA Level and Global Earth Temperature Changes have Common Oscillations
NASA Astrophysics Data System (ADS)
Singular Spectrum Analysis (SSA) of Global Mean Sea Level (GMSL) and Global Average Earth Temperature (HadCRUT4) data revealed presence of quasiperiodic components with periods of 60, 20 and 10 years in both time series. 60-year component of sea level is anticorrelated with long-periodic changes in temperature, while 10 and 20-year components are correlated. The question what can be the nature of these common oscillations is discussed.
Zotov, L. V.
Image Representations of Complete Urban Surface Temperatures
Urban areas are characterized by a strongly three?dimensional structure in which vertical surfaces can comprise a significant component of the total surface area. Two?dimensional images of radiometric surface temperature obtained from remote sensors suffer from anisotropy and may provide biased representations of the actual complete urban surface temperature. In this paper, directional radiometric surface temperatures and a GIS of building
J. A. Voogt
High-temperature Mars-to-Earth transfer of meteorite ALH84001
Martian meteorites provide crucial insights into Martian evolution and interplanetary mass transfer, including the potential for exogenesis. ALH84001 is the oldest Martian meteorite discovered so far, and has been used to derive important conclusions about Martian surface temperatures and very low-temperature Mars-to-Earth transfer. To better constrain the thermal evolution and shock metamorphic history of ALH84001, we applied (U�Th)\\/He thermochronometry to
Kyoungwon Min; Peter W. Reiners
MODIS Global Sea Surface Temperature
NASA Technical Reports Server (NTRS)
Every day the Moderate-resolution Imaging Spectroradiometer (MODIS) measures sea surface temperature over the entire globe with high accuracy. This false-color image shows a one-month composite for May 2001. Red and yellow indicates warmer temperatures, green is an intermediate value, while blues and then purples are progressively colder values. The new MODIS sea surface temperature product will be particularly useful in studies of temperature anomalies, such as El Nino, as well as research into how air-sea interactions drive changes in weather and climate patterns. In the high resolution image, notice the amazing detail in some of the regional current patterns. For instance, notice the cold water currents that move from Antarctica northward along South America's west coast. These cold, deep waters upwell along an equatorial swath around and to the west of the Galapagos Islands. Note the warm, wide currents of the Gulf Stream moving up the United States' east coast, carrying Caribbean warmth toward Newfoundland and across the Atlantic toward Western Europe. Note the warm tongue of water extending from Africa's east coast to well south of the Cape of Good Hope. MODIS was launched in December 1999 aboard NASA's Terra satellite. For more details on this and other MODIS data products, please see NASA Unveils Spectacular Suite of New Global Data Products from MODIS. Image courtesy MODIS Ocean Group, NASA GSFC, and the University of Miami
Isotope fractionation in surface ionization ion source of alkaline-earth iodides
The relationship between the isotope fractionation of alkaline-earth elements in the surface ionization ion source and the evaporation filament current, i.e., filament temperature, was studied. It was confirmed that the isotope fractionation depends on the evaporation filament temperature; the isotope fractionation in the case of higher temperature of filament becomes larger. The ionization and evaporation process in the surface ionization ion source was discussed, and it was concluded that the isotope fractionation is suppressed by setting at the lower temperature of evaporation filament because the dissociations are inhibited on the evaporation filament.
Suzuki, T.; Kanzaki, C.; Nomura, M.; Fujii, Y. [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8550 (Japan)
Earth's field NMR; a surface moisture detector?
NASA Astrophysics Data System (ADS)
Earth's field NMR (EFNMR), being free of magnets, would be an ideal teaching medium as well as a mobile NMR technique except for its weak S/N. The common EFNMR apparatus uses a powerful prepolarization field to enhance the spin magnetization before the experiment. We introduce a coil design geared to larger but manageable samples with sufficient sensitivity without prepolarization to move EFNMR closer to routine use and to provide an inexpensive teaching tool. Our coil consists of parallel wires spread out on a plywood to form a current sheet with the current return wires separated so they will not influence the main part of the coil assembly. The sensitive region is a relatively thin region parallel to the coil and close to it. A single turn of the coil is wound to be topologically equivalent to a figure-8. The two crossing segments in the center of a figure-8 form two of the parallel wires of the flat coil. Thus, a two-turn figure-8 has four crossing wires so its topologically equivalent coil will have four parallel wires with currents in phase. Together with the excellent sensitivity, this coil offers outstanding interference rejection because of the figure-8 geometry. An example of such a coil has 328 parallel wires covering a �1 meter square plywood which yields a good NMR signal from 26 liters of water spread out roughly over the area of the coil in less than one minute in a nearby park.
Fukushima, Eiichi; Altobelli, Stephen; McDowell, Andrew; Zhang, Tongsheng
Historical Landsat data comparisons: illustrations of the Earth's changing surface
The U.S. Geological Survey's (USGS) EROS Data Center (EDC) has managed the Landsat data archive for more than two decades. This archive provides a rich collection of information about the Earth's land surface. Major changes to the surface of the planet can be detected, measured, and analyzed using Landsat data. The effects of desertification, deforestation, pollution, cataclysmic volcanic activity, and other natural and anthropogenic events can be examined using data acquired from the Landsat series of Earth-observing satellites. The information obtainable from the historical and current Landsat data play a key role in studying surface changes through time. This document provides an overview of the Landsat program and illustrates the application of the data to monitor changes occurring on the surface of the Earth. To reveal changes that have taken place within the past 20 years, pairs and triplicates of images were constructed from the Landsat multispectral scanner (MSS) and thematic mapper (TM) sensors. Landsat MSS data provide a historical record of the Earth's land surface from the early 1970's to the early 1990's. Landsat TM data provide land surface information from the early 1980's to the present.
U.S. Geological Survey
External Resource: Surface Air Temperature Trends of the Caribbean
NSDL National Science Digital Library
This activity allows learners/students to use real satellite data to determine the changes in near-surface air temperature at different times of the year over the Caribbean Sea. Upon completion of the activity, learners should be able to state how Earth's
Daily High-Resolution-Blended Analyses for Sea Surface Temperature
Two new high-resolution sea surface temperature (SST) analysis products have been developed using optimum interpolation (OI). The analyses have a spatial grid resolution of 0.25� and a temporal resolution of 1 day. One product uses the Advanced Very High Resolution Radiometer (AVHRR) infrared satellite SST data. The other uses AVHRR and Advanced Microwave Scanning Radiometer (AMSR) on the NASA Earth
Richard W. Reynolds; Thomas M. Smith; Chunying Liu; Dudley B. Chelton; Kenneth S. Casey; Michael G. Schlax
Current Tropical Sea Surface Temperatures
NSDL National Science Digital Library
This animation shows the most recent Sea Surface Temperature (SST) data available for the Gulf of Mexico and the Atlantic Coast region. Users can see the progression of warm waters (shown in yellow, orange, and red) slowly filling the Gulf of Mexico. This natural annual warming contributes to the possible formation of hurricanes in the Gulf. The animation updates every 24 hours, and still images of the data are also available. There is also imagery of the most recent 10-day average of SST anomalies in the Pacific Ocean, which is used by scientists for studying El Nino and La Nina. Warmer colors (yellow, red, orange) indicate positive anomalies (temperatures above normal). The imagery is from the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard the National Aeronautics and Space Administration's (NASA) Aqua satellite.
A Low Temperature Limit for Life on Earth
There is no generally accepted value for the lower temperature limit for life on Earth. We present empirical evidence that free-living microbial cells cooling in the presence of external ice will undergo freeze-induced desiccation and a glass transition (vitrification) at a temperature between ?10�C and ?26�C. In contrast to intracellular freezing, vitrification does not result in death and cells may survive very low temperatures once vitrified. The high internal viscosity following vitrification means that diffusion of oxygen and metabolites is slowed to such an extent that cellular metabolism ceases. The temperature range for intracellular vitrification makes this a process of fundamental ecological significance for free-living microbes. It is only where extracellular ice is not present that cells can continue to metabolise below these temperatures, and water droplets in clouds provide an important example of such a habitat. In multicellular organisms the cells are isolated from ice in the environment, and the major factor dictating how they respond to low temperature is the physical state of the extracellular fluid. Where this fluid freezes, then the cells will dehydrate and vitrify in a manner analogous to free-living microbes. Where the extracellular fluid undercools then cells can continue to metabolise, albeit slowly, to temperatures below the vitrification temperature of free-living microbes. Evidence suggests that these cells do also eventually vitrify, but at lower temperatures that may be below ?50�C. Since cells must return to a fluid state to resume metabolism and complete their life cycle, and ice is almost universally present in environments at sub-zero temperatures, we propose that the vitrification temperature represents a general lower thermal limit to life on Earth, though its precise value differs between unicellular (typically above ?20�C) and multicellular organisms (typically below ?20�C). Few multicellular organisms can, however, complete their life cycle at temperatures below ??2�C.
Clarke, Andrew; Morris, G. John; Fonseca, Fernanda; Murray, Benjamin J.; Price, Hannah C.
A study of surface temperatures, clouds and net radiation
NASA Technical Reports Server (NTRS)
The study is continuing and it is focused on examining seasonal relationships between climate parameters such as the surface temperatures, the net radiation and cloud types and amount on a global basis for the period February 1985 to January 1987. The study consists of an analysis of the combined Earth Radiation Budget Experiment (ERBE) and International Satellite Cloud Climatology Program (ISCCP) products. The main emphasis is on obtaining the information about the interactions and relationships of Earth Radiation Budget parameters, cloud and temperature information. The purpose is to gain additional qualitative and quantitative insight into the cloud climate relationship.
Dhuria, Harbans
MY NASA DATA Lesson Plan A: Circle the Earth-Explore Surface Types on a Journey around Earth
NSDL National Science Digital Library
This lesson plan uses NASA Clouds and Earth's Radiant Energy System (CERES) instrument percent coverage surface data with a world map to locate landmasses and bodies of water at the Earth's Equator. When using satellites to study Earth system processes, especially atmospheric processes, it is important to know what is the background that one is seeing on the Earth. This lesson provides an introduction to exploring Earth surface types. The percent water along the Equator is about 77 percent, which is surprisingly representative of the entire planet. At 40N latitude, the percentage water is about 55 percent, so any single latitude is not necessarily representative of the Earth as a whole.
Surface Temperature Estimation of Gangotri Glacier Using Thermal Remote Sensing
NASA Astrophysics Data System (ADS)
Land surface temperature (LST) is important factor in global climate change studies, for estimating radiation into heat balance studies and as a control for climate change models. The knowledge of surface temperature is important to a range of issues and themes in earth sciences, climate change and human interactions with environment. In this investigation an attempt has been made to estimate surface temperature from ASTER and Landsat Thermal Band data for the Gangotri Glacier. ASTER and Landsat Calibration had been performed to convert digital numbers to exoatmospheric radiance using published post-launch gains and offsets. The exoatmospheric radiance is then converted to surface radiance by applying the Emissivity Normalization method, assuming the emissivity of the Investigation area is constant (0.97, the emissivity of glacier ice). The surface temperature is then extracted from the surface radiance. Based on images from Oct 1990, 2001 and 2010 mean temperatures of 15.763, 15.893 and 17.154 respectively, are inferred. The extracted temperature data were compared to observed temperatures and showed a good correlation, with differences of 1-2oc.The variability of these retrieved Land surface Temperatures has been investigated with respect snout point, ELA and highest point of Gangotri Glacier determined from the Landsat visible bands and ASTER DEM. The emissivity per pixel is retrieved directly from satellite data and has been estimated as narrow band emissivity at the satellite sensor channel in order to minimize the errors in the land surface temperature estimation of study area.
Anul Haq, M.; Jain, K., , Dr.; Menon, K. P. R., , Dr.
Ocean surfaces on Snowball Earth: implications for survival of surface life
NASA Astrophysics Data System (ADS)
The ocean surfaces on a Neoproterozoic Snowball Earth would vary with latitude and evolve through time. The high-latitude and mid-latitude oceans would consist of snow-covered sea-glaciers (self-sustaining ice shelves), with surface albedo 0.8. At low latitudes in regions of net sublimation, the ocean surfaces would consist of (1) bare sea ice with salt inclusions, (2) an evaporite deposit of hydrohalite, and (3) bubbly glacier ice emerging from equatorward flow of sea-glaciers. Their albedos would be 0.6-0.75. These high albedos, when used in climate models for the early part of the snowball event, imply surface air temperatures well below freezing at all latitudes in all seasons. Yet there is evidence that photosynthetic eukaryotic algae survived the snowball events, requiring liquid water at or near the surface. Possible locations for survival of surface life are (a) at geothermal hotspots on coastlines, (b) in the ocean under widespread thin tropical sea ice, and (c) in enclosed tropical seas or lakes under thin ice. Radiative transfer modeling of the penetration of sunlight, estimates of sublimation rates from climate models, and computation of ice velocities from ice-flow models of sea-glaciers, indicate that ice on the tropical ocean would have been several hundred meters thick, ruling out (b). Thin ice might survive on a lake or nearly-landlocked sea with low salt content, beyond reach of the sea-glaciers. However, only a narrow range of conditions would allow a refugium under such ice to persist. The most likely refugium is therefore isolated geothermal hotspots, as proposed by Hoffman and Schrag. References: (1) Warren, S.G., R.E. Brandt, T.C. Grenfell, and C.P. McKay, 2002: Snowball Earth: Ice thickness on the tropical ocean. J. Geophys. Res. (Oceans), 107, 10.1029/2001JC001123. (2) Warren, S.G., D. Pollard, and R.E. Brandt, 2002: Ocean surfaces on Snowball Earth. In preparation.
Warren, S.
Global distribution of Earth's surface shortwave radiation budget
The monthly mean shortwave (SW) radiation budget at the Earth's surface (SRB) was computed on 2.5-degree longitude-latitude resolution for the 17-year period from 1984 to 2000, using a radiative transfer model accounting for the key physical parameters that determine the surface SRB, and long-term climatological data from the International Satellite Cloud Climatology Project (ISCCP-D2). The model input data were supplemented
N. Hatzianastassiou; C. Matsoukas; A. Fotiadi; K. G. Pavlakis; E. Drakakis; D. Hatzidimitriou; I. Vardavas
Characteristics of the solar signal on the Earth's surface through stratosphere-troposphere coupled process
NASA Astrophysics Data System (ADS)
Solar influence on climate has been discussed since long time on the assumption that the total solar irradiance (TSI) directly affects Earth's surface. Recent measurements from the space revealed that the variation of the TSI associated with the 11-year solar cycle is about 0.1%, which cannot produce little effect on Earth's climate without a feedback from the atmosphere-ocean system. Several amplifying mechanism are proposed for different variation of solar origin, cosmic ray, visible light, solar ultra violet. To determine which process is actually operating in the Earth's atmosphere, it needs to investigate not only the global mean temperature, but also its spatial structure. Observed 11-year solar signals in surface temperature can be characterizes by warming in midlatitudes and the absence of warming (or even slight cooling) in the tropics. Midlatitudes warming of the surface temperature occurs in associated with a downward penetration of stratospheric polar-night jet or the polar-night jet oscillation. Little change in tropical surface temperature is consistent with dynamical nature. Meridional circulation change produces a warming in the tropical lower stratosphere, but little effect on the tropospheric temperature. Such characteristics of solar signal can be expected from that produced through change of the solar ultraviolet. Change of the solar heating in the middle atmosphere modulates wave mean-flow interaction in the stratosphere through two processes: one is the polar-night jet oscillation, and the other is a modulation of the meridional circulation.
Kodera, Kunihiko
Amplification of surface temperature trends and variability in thetropical atmosphere
The month-to-month variability of tropical temperatures is larger in the troposphere than at the Earth's surface. This amplification behavior is similar in a range of observations and climate model simulations, and is consistent with basic theory. On multi-decadal timescales, tropospheric amplification of surface warming is a robust feature of model simulations, but occurs in only one observational dataset. Other observations
B. D. Santer; T. M. L. Wigley; C. Mears; F. J. Wentz; S. A. Klein; D. J. Seidel; K. E. Taylor; P. W. Thorne; M. F. Wehner; P. J. Gleckler; J. S. Boyle; W. D. Collins; K. W. Dixon; C. Doutriaux; M. Free; Q. Fu; J. E. Hansen; G. S. Jones; T. R. Karl; J. R. Lanzante; G. A. Meehl; V. Ramaswamy; G. Russell; G. A. Schmidt
MY NASA DATA: Circle the Earth - Explore Surface Types on a Journey around Earth
NSDL National Science Digital Library
The CERES (Clouds and Earth's Radiant Energy System) satellite instrument gathers data on Earth's surface coverage; this lesson provides an introduction to coverage types and percentages by using that data from two geographic areas: the equator and 40°N. Students will use a world map to locate a series of points by latitude and longitude, determine if each point is covered by land or water, and then compare their findings to those from the CERES data. Accompanying questions prompt students to offer possible explanations for differences between their assessment of coverage type and the satellite data. This lesson uses student- and citizen science-friendly microsets of authentic NASA Earth system science data from the MY NASA DATA project. It also includes related links, extensions, and an online glossary.
Eutectic melting temperature of the lowermost Earth's mantle
NASA Astrophysics Data System (ADS)
Partial melting of the Earth's deep mantle probably occurred at different stages of its formation as a consequence of meteoritic impacts and seismology suggests that it even continues today at the core-mantle boundary. Melts are important because they dominate the chemical evolution of the different Earth's reservoirs and more generally the dynamics of the whole planet. Unfortunately, the most critical parameter, that is the temperature profile inside the deep Earth, remains poorly constrained accross the planet history. Experimental investigations of the melting properties of materials representative of the deep Earth at relevant P-T conditions can provide anchor points to refine past and present temperature profiles and consequently determine the degree of melting at the different geological periods. Previous works report melting relations in the uppermost lower mantle region, using the multi-anvil press [1,2]. On the other hand, the pyrolite solidus was determined up to 65 GPa using optical observations in the laser-heated diamond anvil cell (LH-DAC) [3]. Finally, the melting temperature of (Mg,Fe)2SiO4 olivine is documented at core-mantle boundary (CMB) conditions by shock wave experiments [4]. Solely based on these reports, experimental data remain too sparse to draw a definite melting curve for the lower mantle in the relevant 25-135 GPa pressure range. We reinvestigated melting properties of lower mantle materials by means of in-situ angle dispersive X-ray diffraction measurements in the LH-DAC at the ESRF [5]. Experiments were performed in an extended P-T range for two starting materials: forsterite and a glass with chondrite composition. In both cases, the aim was to determine the onset of melting, and thus the eutectic melting temperatures as a function of pressure. Melting was evidenced from drastic changes of diffraction peak shape on the image plate, major changes in diffraction intensities in the integrated pattern, disappearance of diffraction rings, and changes in the relation between sample-temperature and laser-power. In this work, we show that temperatures higher than 4000 K are necessary for melting mean mantle at the 135 GPa pressure found at the core mantle boundary (CMB). Such temperature is much higher than that from estimated actual geotherms. Therefore, melting at the CMB can only occur if (i) pyrolitic mantle resides for a very long time in contact with the outer core, (ii) the mantle composition is severely affected by additional elements depressing the solidus such as water or (iii) the temperature gradient in the D" region is amazingly steep. Other implications for the temperature state and the lower mantle properties will be presented. References (1) Ito et al., Phys. Earth Planet. Int., 143-144, 397-406, 2004 (2) Ohtani et al., Phys. Earth Planet. Int., 100, 97-114, 1997 (3) Zerr et al., Science, 281, 243-246, 1998 (4) Holland and Ahrens, Science, 275, 1623-1625, 1997 (5) Schultz et al., High Press. Res., 25, 1, 71-83, 2005.
Andrault, D.; Lo Nigro, G.; Bolfan-Casanova, N.; Bouhifd, M.; Garbarino, G.; Mezouar, M.
Surface reactions on rare earth metals monitored by work function measurements
Surface reactions on clean, oxidized, and partially hydrided rare earth metal films with O/sub 2/, H/sub 2/, H/sub 2/O, CO, and CO/sub 2/ were monitored by dynamic work function measurements under ultrahigh vacuum conditions. The work function data are discussed in the light of electron spectroscopic evidence, where available. The main results of this study are: Initial oxidation of Yb seems to follow a different oxidation mechanism as compared to other rare earth metals. Reaction of H/sub 2/O with clean oxidized, and hydrided rare earth metal surfaces yields surface hydroxyl species. H/sub 2/ uptake on divalent Yb metal is much slower than on trivalent Er metal, but occurs at a comparable rate on the oxidized systems. On oxidized surfaces, surface OH formation is substantiated for room-temperature reaction with H/sub 2/. The ..delta.. phi data indicate high reactivity of CO and CO/sub 2/ toward clean rare earth metal surfaces and are consistent with dissociative adsorption of both molecules.
Strasser, G.; Bertel, E.; Netzer, F.P.
Common oscillations in Global Earth Temperature, Sea Level, and Earth rotation
NASA Astrophysics Data System (ADS)
Singular Spectrum Analysis (SSA) of Global Mean Sea Level (GMSL) and Global Average Earth Temperature (HadCRUT4) data after global warming trends subtraction revealed presence of quasi-periodic components with periods of 60, 20 and 10 years in both time series. 60-year component of sea level is anticorrelated with long-periodic changes in temperature, while 10 and 20-year components are correlated. Simultaneous presence of 60-year component in secular Earth rotation rate changes rises a question of interrelations between Earth rotation and Climate. Quasi-20-year changes in GMSL and HadCRUT4 have maxima and minima well corresponding to the amplitude changes of recently reconstructed Chandler wobble excitation, which could be caused by the 18.6-year cycle of the Moon orbital nodes regression. The cause of 10-year oscillations in climate characteristics is enigmatic. It could be related to El Nino variability, Volcanoes, or Solar activity, but correlation with each of those processes found to be small. Looks like it is correlated with 9.3 yr tidal wave.
Zotov, Leonid; Bizouard, Christian; Sidorenkov, Nikolay
Concept of a space optoelectronic system for environmental monitoring of the near-earth space, atmosphere, and earth surface
The sharp increase of the man-induced pressure on the environment and hence the need to predict and monitor natural anomalies makes global monitoring of the ecosphere of planet Earth an issue of vital importance. The notion of the ecosphere covers three basic shells closely interacting with each other: the near-Earth space, the atmosphere and the Earth surface. In the near-Earth
Anatoli V. Eltsov; Vladimir I. Karasev; Vjacheslav V. Kolotkov; Timothy V. Kondranin
The aim of our study to develop a method for the estimation of the early night-time near-surface air UHI pattern based on surface temperature data in Szeged, Hungary. The surface temperature data have been collected by airplane based thermal infrared sensor. The study area was covered by several hundreds of images with the spatial resolution of about 2 m. Simultaneous
J�nos Unger; Tam�s G�l; J�nos Rakonczai; L�szl� Mucsi; J�nos Szatm�ri; Zal�n Tobak
A much warmer Earth surface for most of geologic time: implications to biotic weathering
NASA Technical Reports Server (NTRS)
The authors present two scenarios for the temperature history of Earth. One scenario is conventional, the other relies on a warmer history. Both scenarios include surface cooling determined by the evolution of the biosphere and are similar until the Proterozoic period. The warmer scenario requires a higher plant/lichen terrestrial biota to increase weathering intensity. Justification for a warmer surface includes period temperatures from the oxygen isotope record of coexisting phosphates and cherts, an upper limit of 58 degrees C from primary gypsum precipitation, and the lack of fractionation of sulfur isotopes between sulfide and sulfates in Archean sediments.
Schwartzman, D. W.; McMenamin, M.
Concept of a space optoelectronic system for environmental monitoring of the near-earth space, atmosphere, and earth surface
NASA Astrophysics Data System (ADS)
The sharp increase of the man-induced pressure on the environment and hence the need to predict and monitor natural anomalies makes global monitoring of the ecosphere of planet Earth an issue of vital importance. The notion of the ecosphere covers three basic shells closely interacting with each other: the near-Earth space, the atmosphere and the Earth surface. In the near-Earth space (covering 100 to 2000 km altitudes) the primary objects of monitoring are: functioning artificial space objects, the fragments of their constructions or space rubbish (which by estimation amounts to 3.5 million pieces including 30,000 to 70,000 objects having dimensions sufficient for heavy damaging or even destroying functioning space objects) and objects of space origin (asteroids, meteorites and comets) whose trajectories come closely enough to the Earth. Maximum concentrations of space rubbish observed on orbits with altitudes of 800, 1000 and 1500 km and inclinations of 60 to 100 deg. are related in the first place to spacecraft launch requirements. Taking into account the number of launches implemented by different countries in the framework of their own space programs the probability of collision of functioning spacecraft with space rubbish may be estimation increase from (1.5 - 3.5)% at present to (15 - 40)% by 2020. Besides, registration of space radiation flow intensity and the solar activity is no less important in this space area. Subject to control in the atmosphere are time and space variations in temperature fields, humidity, tracing gas concentrations, first of all ozone and greenhouse gases, the state of the cloud cover, wind velocity, etc. The range of objects to be under environmental management of Earth surface is just as diverse and essentially should include the state of the surface and the near-surface layer of seas and oceans, internal reservoirs, the cryosphere and the land surface along with vegetation cover, natural resources and human activities. No matter how large the space (from several meters to hundreds of kilometers) and time (from an hour to several months) scales of the above monitoring might be there is a common dominating factor which could favor creation of a general- purpose observation and control system based on passive optoelectronic instrumentation of different levels of sophistication. This dominating factor refers to the possibility of obtaining information about the state of objects by way to recording parameters of radiation emitted by them in wavelengths of 250 nm to tens of microns. The fact that phenomena and processes occurring in the atmosphere are closely interrelated gives implications as to the structure of such a system which is supposed to be a common information network basically consisting of an orbiting constellation of a number of small-size spacecraft equipped with optoelectronic instrumentation of different complexity, and a ground segment to provide acquisition and processing of information about the status of every ecosphere shell including comprehensive thematic analysis. The existing domestic (based on the `Meteor', `Resurs-O', `Okean', etc. spacecraft) and foreign (NOAA, SPOT, LANDSAT, ERS, etc.) space systems are designed for solution of only a limited number of atmosphere monitoring issues, namely those related to meteorology and studies of natural resources. As for the near-Earth space there are at present only ground facilities whose monitoring capabilities are also limited. It should be noted that in recent years in the USA similar activities have been in full swing targeted at creation of a system like the one mentioned above (the Earth Observation System). A system comprising four spacecraft of the NOAA series and a distributed ground network for receiving analog (with 4 km spatial resolution) and digital (with 1 km spatial resolution) multispectral data pertaining to the status of the atmosphere and the underlying surface is currently operational. This system presents some unique features which make it in several applications superior to existing counterparts. The
Eltsov, Anatoli V.; Karasev, Vladimir I.; Kolotkov, Vjacheslav V.; Kondranin, Timothy V.
Ocean Currents and Sea Surface Temperature
NSDL National Science Digital Library
In this classroom activity, students access sea surface temperature and wind speed data from a NASA site, plot and compare data, draw conclusions about surface current and sea surface temperature, and link their gained understanding to concerns about global climate change.
Carter, Joan; Collection, Nasa -.
GISS analysis of surface temperature change
We describe the current GISS analysis of surface temperature change for the period 1880-1999 based primarily on meteorological station measurements. The global surface temperature in 1998 was the warmest in the period of instrumental data. The rate of temperature change was higher in the past 25 years than at any previous time in the period of instrumental data. The warmth
J. Hansen; R. Ruedy; J. Glascoe; M. Sato
Twentieth-century sea surface temperature trends
An analysis of historical sea surface temperatures provides evidence for global warming since 1900, in line with land-based analyses of global temperature trends, and also shows that over the same period, the eastern equatorial Pacific cooled and the zonal sea surface temperature gradient strengthened. Recent theoretical studies have predicted such a pattern as a response of the coupled ocean-atmosphere system
M. A. Cane; A. C. Clement; A. Kaplan
The face of the Earth and the changing sea surface
NASA Astrophysics Data System (ADS)
During the last decades, altimeter satellites have provided high-resolution mapping of the sea surface height, with high-precision and global coverage. The sea surface height above a reference ellipsoid consists of two components: a permanent component, called 'mean sea surface' that coincides with the geoid (an equipotential surface of the Earth's gravity field) and a time-variable component above the geoid, resulting from ocean dynamics (tides, currents, etc.). Altimeter satellites have revealed that at short and medium wavelengths (~ 500 km or less), highs and lows of the mean sea surface reflect seafloor tectonic features, hence ocean bottom topography. Satellite-based mean sea surface data have thus been used to provide global, high-resolution bathymetric maps. With the ever increasing precision of altimetry-based sea surface height measurements (now on the order of 1-2 cm) and of space-based geoid models, it has become possible to measure the so-called 'ocean dynamic topography' (the sea surface topography above the geoid caused by large-scale ocean circulation), hence ocean currents. Since the early 1990s, altimeter satellites also measure global mean sea level rise due to ocean warming and land ice melt (two consequences of present-day anthropogenic global warming). They also provide unique information on the regional variability in sea level change. Regional trend patterns in sea level result from a variety of factors, including non-uniform thermal expansion of sea waters and changes in ocean salinity, as well as deformations of ocean basins (and gravitational changes) due to the viscous/elastic response of the solid Earth to changing loads, in particular those associated with last deglaciation and current land ice melt.
Cazenave, Anny
Anthropogenic disturbance of element cycles at the Earth's surface.
The extent to which humans are modifying Earth's surface chemistry can be quantified by comparing total anthropogenic element fluxes with their natural counterparts (Klee and Graedel, 2004). We quantify anthropogenic mass transfer of 77 elements from mining, fossil fuel burning, biomass burning, construction activities, and human apportionment of terrestrial net primary productivity, and compare it to natural mass transfer from terrestrial and marine net primary productivity, riverine dissolved and suspended matter fluxes to the ocean, soil erosion, eolian dust, sea-salt spray, cosmic dust, volcanic emissions, and for helium, hydrodynamic escape from the Earth's atmosphere. We introduce an approach to correct for losses during industrial processing of elements belonging to geochemically coherent groups, and explicitly incorporate uncertainties of element mass fluxes through Monte Carlo simulations. We find that at the Earth's surface anthropogenic fluxes of iridium, osmium, helium, gold, ruthenium, antimony, platinum, palladium, rhenium, rhodium and chromium currently exceed natural fluxes. For these elements mining is the major factor of anthropogenic influence, whereas petroleum burning strongly influences the surficial cycle of rhenium. Our assessment indicates that if anthropogenic contributions to soil erosion and eolian dust are considered, anthropogenic fluxes of up to 62 elements surpass their corresponding natural fluxes. PMID:22803636
Sen, Indra S; Peucker-Ehrenbrink, Bernhard
Synthesis of complex hydrocarbon systems at temperatures and pressures corresponding to the Earth�s upper mantle conditions
In this work, we presented the results of analyzing the products of abiotic synthesis at temperatures and pressures corresponding to the Earth�s upper mantle conditions. We showed for the first time that the syn? thesis products are petroleum systems the composition of which is similar to that of the hydrocarbon part of natural gas. It was also found that the
V. G. Kutcherov; A. Yu. Kolesnikov; T. I. Dyuzheva; L. F. Kulikova; N. N. Nikolaev; O. A. Sazanova; V. V. Braghkin
Microclimatic Temperature Relationships over Different Surfaces.
ERIC Educational Resources Information Center
Describes a study of temperature variations over different surfaces in an urban campus setting. Explains that researchers sampled temperatures over grass, bare soil, gravel, concrete, and blacktop. Reports that grassy areas registered the highest morning temperatures and lowest afternoon temperatures. (SG)
Williams, Thomas B.
Transport of radon and thoron at the earth's surface
This report covers progress under the current funding period Jan. 1, 1991 to Jan. 1, 1992 and presents the continuation proposal for Jan. 1, 1992 to Jan. 1, 1993. The previous progress report was submitted in May 1990, so activities during the last half of 1990 will also be included. Major activities over the last year have centered on the study of disequilibrium of radon progeny near the earth's surface and the sources of thoron in indoor air. In addition, we have carried out supplemental measurements of radon sorption coefficients in porous materials focusing on the physical mechanism of sorption.
Schery, S.D.
Factors Changing Earth's Surface (title provided or enhanced by cataloger)
NSDL National Science Digital Library
This Classroom Connectors lesson plan discusses the factors which cause changes to the surface of the Earth. This includes identifying various types of landforms, geologic structures and movements, processes that form rocks, and understanding rock and soil cycles. The site provides goals, objectives, an outline, time required, materials, activities, and closure ideas for the lesson. The Classroom Connectors address content with an activity approach while incorporating themes necessary to raise the activity to a higher cognition level. The major motivation is to employ instructional strategies that bring the students physically and mentally into touch with the science they are studying.
Assimilation of Surface Temperature in Land Surface Models
NASA Technical Reports Server (NTRS)
Hydrological models have been calibrated and validated using catchment streamflows. However, using a point measurement does not guarantee correct spatial distribution of model computed heat fluxes, soil moisture and surface temperatures. With the advent of satellites in the late 70s, surface temperature is being measured two to four times a day from various satellite sensors and different platforms. The purpose of this paper is to demonstrate use of satellite surface temperature in (a) validation of model computed surface temperatures and (b) assimilation of satellite surface temperatures into a hydrological model in order to improve the prediction accuracy of soil moistures and heat fluxes. The assimilation is carried out by comparing the satellite and the model produced surface temperatures and setting the "true"temperature midway between the two values. Based on this "true" surface temperature, the physical relationships of water and energy balance are used to reset the other variables. This is a case of nudging the water and energy balance variables so that they are consistent with each other and the true" surface temperature. The potential of this assimilation scheme is demonstrated in the form of various experiments that highlight the various aspects. This study is carried over the Red-Arkansas basin in the southern United States (a 5 deg X 10 deg area) over a time period of a year (August 1987 - July 1988). The land surface hydrological model is run on an hourly time step. The results show that satellite surface temperature assimilation improves the accuracy of the computed surface soil moisture remarkably.
Lakshmi, Venkataraman
Sea surface temperature measurements with AIRS
NASA Technical Reports Server (NTRS)
The comparison of global sea surface skin temperature derived from cloud-free AIRS super window channel at 2616 cm-1 (sst2616) with the Real-Time Global Sea Surface Temperature for September 2002 shows surprisingly small standard deviation of 0.44K.
Aumann, H.
Dynamic Surface Temperature Measurements in ICs
Measuring techniques of the die surface temperature in integrated circuits are reported as very appropriate for failure analysis, for thermal characterization, and for testing modern devices. The paper is arranged as a survey of techniques oriented towards measuring the temperature dynamics of the circuit surface and presenting and discussing both the merits and drawbacks of each technique with regard to
Josep Altet; Wilfrid Claeys; Stefan Dilhaire; Antonio Rubio
Surface temperature excess in heterogeneous catalysis
In this dissertation we study the surface temperature excess in heterogeneous catalysis. For heterogeneous reactions, such as gas-solid catalytic reactions, the reactions take place at the interfaces between the two phases: the gas and the solid catalyst. Large amount of reaction heats are released at the interface for strong exothermic reactions, which makes it possible that the catalyst surface temperatures
L. Zhu
Middle Pliocene sea surface temperatures: A global reconstruction
Identification and analyses of Pliocene marine microfossils from 64 globally distributed stratigraphic sequences have been used to produce a middle Pliocene sea surface temperature reconstruction of the Earth. This reconstruction shows little or no change from current conditions in low latitude regions and significant warming of the ocean surface at mid and higher latitudes of both hemispheres. This pattern of warming is consistent with terrestrial records and suggests a combination of enhanced meridional ocean heat transport and enhanced greenhouse effect were responsible for the middle Pliocene warmth.
Dowsett, H.; Barron, J.; Poore, R.
Synthetic Temperature Profile in the Gulf of Mexico. Part 1. Statistical Relationship Between Modal Amplitudes and Dynamic Height at Surface.
National Technical Information Service (NTIS)
The feasibility of estimating temperature profiles (synthetic temperature profiles) from Geodetic Earth Orbiting Satellite (GEOSAT) altimeter-derived sea-surface heights in the Gulf Stream region has been explored. The scheme was based on a statistical re...
D. S. Ko
On the R- approximations of the Earth's surface topography
NASA Astrophysics Data System (ADS)
The determination of a function describing the Earth's surface topography on a generally irregular grid is important for the interpretation of gravity data, calculation of the corrections for the topography and construction of maps of plumb line deviations. Thus, we have the problem of describing a surface D, or more specifically, the problem of constructing an approximation of a surface D that will be used in the calculation of the function (the derivative of the potential with respect to the coordinate ). We can write where are the observation points. If the model of the plane Earth is adopted, the surface D may be represented by a function of two variables , parametrizing points on an equipotential surface. Then, the correction for topographic masses (the gravity reduction) is calculated by the approximate formula , (1) where, in the case of a detailed survey, the plane must be such that (a) approximate formula (1) (ensuring a required accuracy) can be used for all , where is a finite simply connected area in the plane and (b) for all . (2) The main computational procedure consists of the construction of an analytical approximation of the function (3) From its values given on a set of points ; this approximation should be valid on the entire integration domain. The analytical approximation can be constructed by the R-approximation method, which is a variant of the linear integral representation method based upon the Radon-transform. The values used for the construction of the analytical approximation are given, first, immediately at the observation points; second, on a certain set of points of topographic maps on an adequate scale (for example, it is desirable to use topographic maps on a 1:10 000 scale in the case of a detailed gravity survey on a scale 1:25 000); third, on a certain set of characteristic points of the relief (these values must be measured during gravity surveys). The method proposed in this topic for the Earth's topography description with the help of R-approximations is effective for solving various geophysical, geomorphological, an geodetic problems. Using this method, the values of the function describing the topography can be determined on an arbitrary grid. Therefore, the preliminary regularization of initial data, their ordering, and so on, are not required. A smoother topography is reconstructed to within a few centimeters, whereas mountainous topography is reconstructed less accurately (1-3 sm with a height contrast of about 1000 m).
Stepanova, I. E.
30 CFR 717.15 - Disposal of excess rock and earth materials on surface areas.
Code of Federal Regulations, 2013 CFR
...2013-07-01 false Disposal of excess rock and earth materials on surface areas. 717.15 ...§ 717.15 Disposal of excess rock and earth materials on surface areas. Excess rock and earth materials produced from an underground...
Transient electromagnetic field generated by a vertical electric dipole on the surface of a dissipative earth
The problem of electromagnetic pulse propagation over a dissipative earth surface, excited by a vertical electric dipole located on the earth surface, is investigated. By deforming related integrals in the complex frequency domain it is shown that the scattering contribution of the earth, which is formally expressed in terms of several double inf'mite integrals, can be efficiently computed from some
Hussain Haddad; D. C. Chang
Inference of ground surface temperature history from subsurface temperature data: Interpreting ensembles of borehole logs
Ground surface temperature histories (GSTHs) inferred from borehole temperaturedepth (T-z) data are often degraded, to a various extent, by random or systematic noise in theT-z data and in the measurements of thermophysical properties of the earth. To minimize the effects of noise, and hence improve the fidelity of the inferred GSTH, a plausible approach is to perform a simultaneous inversion,
Henry N. Pollack; Po Yu Shen; Shaopeng Huang
Land-surface atmosphere coupling in an earth system model
NASA Astrophysics Data System (ADS)
The interaction between the atmosphere and the strongly heterogeneous land surface is one of the central scientific topics within Earth system sciences and especially climate research. Many processes, such as vegetation dynamics and the development of spatial patterns in the Subtropics and permafrost regions, take place on scales much below the scale of model resolution. Thus, it is an important scientific challenge to consider the influence of sub-scale heterogeneity on the vertical near-surface fluxes of energy and water. Most climate models do not take into account the actual scale of surface heterogeneities. When coupling a heterogeneous surface to the atmosphere often coupling methods are employed, which include the underlying assumption that the horizontal extent of the individual heterogeneity is so small that the turbulent vertical fluxes stemming from the different surface heterogeneities within one grid-box have mixed horizontally below the lowest model level of the atmosphere. This assumption allows a comparatively simple land-surface-atmosphere coupling with a horizontally homogeneous state of the atmosphere, but it may also be the source of significant errors. In order to access the extent of error introduced we designed an experiment in which the results of three different coupling schemes were compared. The first one is a parameter-aggregation scheme, the second a flux-aggregation scheme based on the assumption of a horizontally homogeneous atmosphere on the lowest atmospheric model level and the third one is a coupling scheme which allows, up to a given height, for the atmosphere to be horizontally heterogeneous within a grid-box. These coupling methods were implemented in the land-surface model JSBACH which was then coupled to the general circulation model ECHAM6, both part of the Max Planck Institute for Meteorology's earth system model MPI-ESM. In a first step sensitivity studies are being carried out to gain process understanding and to disentangle the direct effects of the land-surface-atmosphere coupling and the atmospheric response. To evaluate the overall impact, of a given coupling scheme, 20-year-AMIP-type simulations were performed. First analysis indicates that the results obtained with the three coupling schemes do significantly differ. These differences are not only visible on a sub-grid scale e.g. the sub-grid fluxes, but also on the grid-scale the choice of the coupling scheme significantly affects the simulated global climate and large-scale patterns. Furthermore the difference in the simulated climate between using the improved and the standard flux-aggregation scheme are in the same order of magnitude as those between the parameter aggregation scheme and the standard flux-aggregation scheme.
de Vrese, Philipp; Hagemann, Stefan
Pyrometric Gas and Surface Temperature Measurements
NASA Technical Reports Server (NTRS)
A multiwavelength pyrometer possessing advantages over the one- and two-wavelength designs is described. Results of its application to surface temperature measurements of ceramics is presented. Also described is a probe suitable for gas temperature measurements to temperatures > 2600 K. The design of the probe includes a multiwavelength pyrometer with fiber optic input.
Fralick, Gustave; Ng, Daniel
Geologists Use Particles from Galaxy's Far Reaches to Understand Processes at Earth's Surface
... Earth's surface changes from such forces as erosion by rivers. "As scientists who use geochronology ... Earth's past climate cycles, changes in soil erosion, frequency of floods and landslides, and how ...
Progress of Space Studies of the Earth Surface, Meteorology, and Climate 1992- 1993
NASA Technical Reports Server (NTRS)
This report briefly summarizes the progress made by satellite-dependent systems that are necessary to accomplish global earth monitoring and associated studies of the interactions between the earth's atmosphere, land surface, and ocean.
Halpern, D.
Estimation of Surface Air Temperature Over Central and Eastern Eurasia from MODIS Land Surface Temperature
NASA Technical Reports Server (NTRS)
Surface air temperature (T(sub a)) is a critical variable in the energy and water cycle of the Earth.atmosphere system and is a key input element for hydrology and land surface models. This is a preliminary study to evaluate estimation of T(sub a) from satellite remotely sensed land surface temperature (T(sub s)) by using MODIS-Terra data over two Eurasia regions: northern China and fUSSR. High correlations are observed in both regions between station-measured T(sub a) and MODIS T(sub s). The relationships between the maximum T(sub a) and daytime T(sub s) depend significantly on land cover types, but the minimum T(sub a) and nighttime T(sub s) have little dependence on the land cover types. The largest difference between maximum T(sub a) and daytime T(sub s) appears over the barren and sparsely vegetated area during the summer time. Using a linear regression method, the daily maximum T(sub a) were estimated from 1 km resolution MODIS T(sub s) under clear-sky conditions with coefficients calculated based on land cover types, while the minimum T(sub a) were estimated without considering land cover types. The uncertainty, mean absolute error (MAE), of the estimated maximum T(sub a) varies from 2.4 C over closed shrublands to 3.2 C over grasslands, and the MAE of the estimated minimum Ta is about 3.0 C.
Shen, Suhung; Leptoukh, Gregory G.
Do planetary encounters reset surfaces of near Earth asteroids?
NASA Astrophysics Data System (ADS)
Processes such as the solar wind sputtering and micrometeorite impacts can modify optical properties of surfaces of airless bodies. This explains why spectra of the main belt asteroids, exposed to these 'space weathering' processes over eons, do not match the laboratory spectra of ordinary chondrite (OC) meteorites. In contrast, an important fraction of Near Earth Asteroids (NEAs), defined as Q-types in the asteroid taxonomy, display spectral attributes that are a good match to OCs. Here we study the possibility that the Q-type NEAs underwent recent encounters with the terrestrial planets and that the tidal gravity (or other effects) during these encounters exposed fresh OC material on the surface (thus giving it the Q-type spectral properties). We used numerical integrations to determine the statistics of encounters of NEAs to planets. The results were used to calculate the fraction and orbital distribution of Q-type asteroids expected in the model as a function of the space weathering timescale, tsw (see main text for definition), and maximum distance, r?, at which planetary encounters can reset the surface. We found that tsw � 10 6 yr (at 1 AU) and r? � 5 Rpl, where Rpl is the planetary radius, best fit the data. Values tsw < 10 5 yr would require that r? > 20 Rpl, which is probably implausible because these very distant encounters should be irrelevant. Also, the fraction of Q-type NEAs would be probably much larger than the one observed if tsw > 10 7 yr. We found that tsw ? q2, where q is the perihelion distance, expected if the solar wind sputtering controls tsw, provides a better match to the orbital distribution of Q-type NEAs than models with fixed tsw. We also discuss how the Earth magnetosphere and radiation effects such as YORP can influence the spectral properties of NEAs.
Nesvorn�, David; Bottke, William F.; Vokrouhlick�, David; Chapman, Clark R.; Rafkin, Scot
Radar Polarimetric Studies of Near-Earth Asteroid Surface Properties
NASA Astrophysics Data System (ADS)
We use a radar polarimetric technique to study the surface physical properties of a small sample of Near Earth Asteroids (NEAs), to search for evidence of regolith cover, and to correlate the radar polarimetric properties with size and shape. In radar experiments, an analysis of the degree of linear polarization in the received echo can be used to investigate whether there is sub-surface scattering of the incident wave, which would imply the presence of a low dielectric constant surface covering such as a regolith. If a circularly polarized radar wave refracts into a surface that is smooth at wavelength scales and is backscattered toward the radar by embedded scatterers or by an underlying structure, the returned radar echo will have a net linearly polarized component (it will be elliptically polarized). This technique has been applied to 1999 JM8, 4179 Toutatis, and 2004 VG64 (Carter et al., 38th DPS, 2006). Our sample now includes the recently observed objects 2006 VV2 and 2006 AM4 as well as archival asteroid targets selected from past NEA observations at Arecibo Observatory. We will present current results from the new data and reprocessed archival data. This research is funded through the NASA Planetary Astronomy program. Arecibo Observatory is part of the National Astronomy and Ionosphere Center, which is operated by Cornell University under a cooperative agreement with the National Science Foundation.
Carter, Lynn M.; Campbell, D. B.; Nolan, M. C.
UV 380 nm Reflectivity of the Earth's Surface
NASA Technical Reports Server (NTRS)
The 380 nm radiance measurements of TOMS (Total Ozone Mapping Spectrometer) have been converted into a global data set of daily (1979 to 1992) Lambert equivalent reflectivities R of the Earth's surface and boundary layer (clouds, aerosols, surface haze, and snow/ice). Since UV surface reflectivity is between 2 and 8% for both land and water during all seasons of the year (except for ice and snow cover), reflectivities larger than the surface value indicates the presence of clouds, haze, or aerosols in the satellite field of view. Statistical analysis of 14 years of daily data show that most snow/ice-free regions of the Earth have their largest fraction of days each year when the reflectivity is low (R less than 10%). The 380 nm reflectivity data shows that the true surface reflectivity is 2 to 3% lower than the most frequently occurring reflectivity value for each TOMS scene. The most likely cause of this could be a combination of frequently occurring boundary-layer water or aerosol haze. For most regions, the observation of extremely clear conditions needed to estimate the surface reflectivity from space is a comparatively rare occurrence. Certain areas (e.g., Australia, southern Africa, portions of northern Africa) are cloud-free more than 80% of the year, which exposes these regions to larger amounts of UV radiation than at comparable latitudes in the Northern Hemisphere. Regions over rain-forests, jungle areas, Europe and Russia, the bands surrounding the Arctic and Antarctic regions, and many ocean areas have significant cloud cover (R greater than 15%) more than half of each year. In the low to middle latitudes, the areas with the heaviest cloud cover (highest reflectivity for most of the year) are the forest areas of northern South America, southern Central America, the jungle areas of equatorial Africa, and high mountain regions such as the Himalayas or the Andes. The TOMS reflectivity data show the presence of large nearly clear ocean areas and the effects of the major ocean currents on cloud production.
Herman, J. R.; Celarier, E.; Larko, D.
Estimation of ground surface temperatures from borehole temperature data
To infer past climatic changes from temperatures measured in boreholes, one must obtain reliable estimates of ground surface temperature (GST) histories from these data. This paper presents a method that uses a Bayesian inverse technique to estimate the GST in the Fourier frequency domain. By assuming the a priori GST to be stationary, with a prescribed standard deviation and a
Kelin Wang
Longitude: Linking Earth's ancient surface to its deep interior
NASA Astrophysics Data System (ADS)
Earth scientists have had no direct way of calculating longitudes for times before those of the oldest hotspot track eruption sites in the Cretaceous (~ 130 Myr ago). For earlier times palaeomagnetic data constrain only ancient latitudes and continental rotations. We have recently devised a hybrid plate motion reference frame that permits the calculation of longitude back to Pangean assembly at ~ 320 Ma. This reference frame, here corrected for True Polar Wander (TPW), places most reconstructed Large Igneous Provinces (LIPs) of the past 300 Myr radially above the edges of the Large Low Shear wave Velocity Provinces (LLSVPs) in Earth's lowermost mantle. This remarkable correlation between surface and deep mantle features, which is also discernible for all hotspots with a deep-plume origin, provides a new way of reconstructing the original positions of LIP sites, and therefore the position of continents whose longitudes have hitherto been unknown. We place the 258 Ma Emeishan LIP eruption of South China at 4�N and 140�E, in that way constraining the width and the geometry of the Palaeotethys Ocean during the Late Permian. If LLSVPs have remained stable for even longer and TPW has been small, we can, under these assumptions, also restore Siberia and Gondwana longitudinally for Late Devonian (~ 360 Ma) and Late Cambrian (~ 510 Ma) times.
Torsvik, Trond H.; Steinberger, Bernhard; Cocks, L. Robin M.; Burke, Kevin
Method and apparatus for measuring temperature of an earth formation in the presence of a radio frequency electromagnetic field
A method and apparatus for measuring the temperature in a subsurface earth formation that is being heated in situ by subjection to a radio frequency electromagnetic field. It includes lowering a maximum registering thermometer into the formation on a non-conductive flexible line, and holding it there long enough to reach the ambient temperature at that location. Then, the thermometer is raised to the surface fast enough to avoid any significant change on the way up to read that registered maximum.
Kunetka, R.E.; Dowling, D.J.
Urban aerosol effects on surface insolation and surface temperature
NASA Astrophysics Data System (ADS)
Urban aerosol particulates may play a fundamental role in urban microclimates and city-generated mesoscale circulations via its effects on energy balance of the surface. Key questions that need to be addressed include: (1) How do these particles affect the amount of solar energy reaching the surface and resulting surface temperature? (2) Is the effect the same in all cities? and (3) How does it vary from city to city? Using NASA AERONET in-situ observations, a radiative transfer model, and a regional climate mode (MM5), we assess aerosol effects on surface insolation and surf ace temperature for dense urban-polluted regions. Two big cities, one in a developing country (Beijing, P.R. China) and another in developed country (New York City, USA), are selected for inter-comparison. The study reveals that aerosol effects on surface temperature depends largely on aerosols' optical and chemical properties as well as atmosphere and land surface conditions, such as humidity and land cover. Therefore, the actual magnitudes of aerosol effects differ from city to city. Aerosol measurements from AERONET show both average and extreme cases for aerosol impacts on surface insolation. In general, aerosols reduce surface insolation by 30Wm-2. Nevertheless, in extreme cases, such reduction can exceed 100 Wm-2. Consequently, this reduces surface skin temperature 2-10C in an urban environment.
Jin, M.; Burian, S. J.; Remer, L. A.; Shepherd, M. J.
Climatic change by cloudiness linked to the spatial variability of sea surface temperatures
NASA Technical Reports Server (NTRS)
An active role in modifying the earth's climate is suggested for low cloudiness over the circumarctic oceans. Such cloudiness, linked to the spatial differences in ocean surface temperatures, was studied. The temporal variations from year to year of ocean temperature patterns can be pronounced and therefore, the low cloudiness over this region should also show strong temporal variations, affecting the albedo of the earth and therefore the climate. Photographs are included.
Otterman, J.
Climate Data Records of Sea Surface Temperatures
Sea-surface temperature (SST) is a geophysical variable intimately involved in the climate system. It provides the bottom boundary condition for much of the atmosphere, being the primary source of heat for atmospheric energy, and is a potential \\
P. J. Minnett
Laboratory investigations: Low Earth orbit environment chemistry with spacecraft surfaces
NASA Technical Reports Server (NTRS)
Long-term space operations that require exposure of material to the low earth orbit (LEO) environment must take into account the effects of this highly oxidative atmosphere on material properties and the possible contamination of the spacecraft surroundings. Ground-based laboratory experiments at Los Alamos using a newly developed hyperthermal atomic oxygen (AO) source have shown that not only are hydrocarbon based materials effected but that inorganic materials such as MoS2 are also oxidized and that thin protective coatings such as Al2O3 can be breached, producing oxidation of the underlying substrate material. Gas-phase reaction products, such as SO2 from oxidation of MoS2 and CO and CO2 from hydrocarbon materials, have been detected and have consequences in terms of spacecraft contamination. Energy loss through gas-surface collisions causing spacecraft drag has been measured for a few select surfaces and has been found to be highly dependent on the surface reactivity.
Cross, Jon B.
Evaluation of Flat Surface Temperature Probes
NASA Astrophysics Data System (ADS)
The objective of this paper is elaboration of elements related to metrological analysis in the field of surface temperature measurement. Surface temperature measurements are applicable in many fields. As examples, safety testing of electrical appliances and a pharmaceutical production line represent case studies for surface temperature measurements. In both cases correctness of the result of the surface temperature has an influence on final product safety and quality and thus conformity with specifications. This paper deals with the differences of flat surface temperature probes in measuring the surface temperature. For the purpose of safety testing of electrical appliances, surface temperature measurements are very important for safety of the user. General requirements are presented in European standards, which support requirements in European directives, e.g., European Low Voltage Directive 2006/95/EC and pharmaceutical requirements, which are introduced in official state legislation. This paper introduces a comparison of temperature measurements of an attached thermocouple on the measured surface and measurement with flat surface temperature probes. As a heat generator, a so called temperature artifact is used. It consists of an aluminum plate with an incorporated electrical heating element with very good temperature stability in the central part. The probes and thermocouple were applied with different forces to the surface in horizontal and vertical positions. The reference temperature was measured by a J-type fine-wire (0.2 mm) thermocouple. Two probes were homemade according to requirements in the European standard EN 60335-2-9/A12, one with a fine-wire (0.2 mm) thermocouple and one with 0.5mm of thermocouple wire diameter. Additional commercially available probes were compared. Differences between probes due to thermal conditions caused by application of the probe were found. Therefore, it can happen that measurements are performed with improper equipment or in an improper way for a particular application. Therefore, knowledge and awareness regarding all facts related to the used measuring equipment are essential to avoid the risk of a wrong decision on safety measures.
Beges, G.; Rudman, M.; Drnovsek, J.
Earthquake Lights: Time-dependent Earth Surface - Ionosphere Coupling Model
NASA Astrophysics Data System (ADS)
Co-seismic luminescence, commonly referred to as Earthquake lights (EQLs), is an atmospheric luminous phenomenon occurring during strong earthquakes and lasting from a fraction of a second to a few minutes [e.g., Derr, J. S., Bull. Seismol. Soc. Am., 63, 2177, 1973; St-Laurent, F., et al., Phys. Chem. Earth, 31, 305, 2006; Herauld and Lira, Nat. Hazards Earth Syst. Sci., 11, 1025, 2011]. Laboratory experiments of Freund, F. T., et al. [JGR, 105, 11001, 2000; JASTP, 71, 1824, 2009, and references therein] demonstrate that rocks subjected to stress force can generate electric currents. During earthquakes these currents can deliver significant amounts of net positive charge to the ground-air interface leading to enhancements in the electric field and corona discharges around ground objects [Freund et al., 2009]. The eyewitness reports [Herauld and Lira, 2011] indicate similarities of the blue glow observed during EQLs to St. Elmo's fire observed during thunderstorms around wing tips of airplanes or around the tall masts of sailing ships [e.g., Wescott, E.M., et al., GRL, 23, 3687, 1996]. Recent work indicates that the vertical currents induced in the stressed rock can map to ionospheric altitudes and create 10s of % variations in the total electron content in the Earth's ionosphere above the earthquake active region [Kuo, C. L., et al., JGR, 116, A10317, 2011]. The magnitudes of the vertical currents estimated by Kuo et al. [2011] based on work by Freund et al. [2009] range from 0.01 to 10 ?A/m2. In this talk we report results from a new time-dependent model allowing to calculate currents induced in the ambient atmosphere and corona currents under application of vertical stressed rock currents with arbitrary time variation. We will report test results documenting the model performance under conditions: (1) relaxation toward the classic global electric circuit conditions in fair weather regions when ionosphere is maintained at 300 kV with respect to the ground; (2) relaxation toward the steady state conditions when the earth-air surface charge is maintained by balance of the current induced by stressed rock and ambient atmospheric current [Kuo et al., 2011]; and (3) a 2 min duration model episode in which the stressed rock current reaches value of 0.4 ?A/m2 producing electric fields at the ground on the order of 0.5 kV/cm leading to an additional injection of positive corona current. One of the interesting results of this modeling is that the reduced electric field (i.e., field normalized by air density) remains low at the ground-air interface due to the injection of the positive corona charge and at high altitudes due to the naturally high conductivity of the Earth's atmosphere. At the intermediate altitudes in clear air above earthquake region the reduced electric field can dynamically reach values exceeding both relativistic (~2 kV/cm when scaled to the ground level) and conventional (~30 kV/cm ground value) breakdown thresholds. The exact geometry would depend on the spatial extent of the earthquake active region, ambient atmospheric conductivity and the time dynamics of the driving stress rock current. We suggest that the enhancements of the reduced electric field in clear air at high altitudes in the Earth atmosphere is a likely scenario leading to transient (sub-second duration) flashes some time observed during earthquakes [Herauld and Lira, 2011].
Pasko, V. P.
Ocean Remote Sensing: Sea Surface Temperature Imagery
NSDL National Science Digital Library
This site presents rapidly processed estimates of sea surface temperature for various regions along the east coast of the United States, including the Gulf Stream, Chesapeake Bay, the Gulf of Mexico and the Bahamas. The imagery includes both single pass data and composite data from multiple passes. Included at this site is a primer on the measurement of sea surface temperature. Additional links satellite links are provided. See related links for the topics.
Precision radiometric surface temperature (PRST) sensor
NASA Astrophysics Data System (ADS)
There is a need for a Precision Radiometric Surface Temperature (PRST) measurement capability that can achieve noncontact profiling of a sample's surface temperature when heated dynamically during laser processing, aerothermal heating or metal cutting/machining. Target surface temperature maps within and near the heated spot provide critical quantitative diagnostic data for laser-target coupling effectiveness and laser damage assessment. In the case of metal cutting, this type of measurement provides information on plastic deformation in the primary shear zone where the cutting tool is in contact with the workpiece. The challenge in these cases is to measure the temperature of a target while its surface's temperature and emissivity are changing rapidly and with incomplete knowledge of how the emissivity and surface texture (scattering) changes with temperature. Bodkin Design and Engineering, LLC (BDandE), with partners Spectral Sciences, Inc. (SSI) and Space Computer Corporation (SCC), has developed a PRST Sensor that is based on a hyperspectral MWIR imager spanning the wavelength range 2-5 ?m and providing a hyperspectral datacube of 20-24 wavelengths at 60 Hz frame rate or faster. This imager is integrated with software and algorithms to extract surface temperature from radiometric measurements over the range from ambient to 2000K with a precision of 20K, even without a priori knowledge of the target's emissivity and even as the target emissivity may be changing with time and temperature. In this paper, we will present a description of the PRST system as well as laser heating test results which show the PRST system mapping target surface temperatures in the range 600-2600K on a variety of materials.
Daly, James T.; Roberts, Carson; Bodkin, Andrew; Sundberg, Robert; Beaven, Scott; Weinheimer, Jeffrey
Seasonal Changes in Surface Temperatures on Titan
NASA Technical Reports Server (NTRS)
The surface brightness temperatures on Titan have been measured by the Composite Infrared Spectrometer (CIRS) aboard Cassini during the period spanning late northern winter through vernal equinox. CIRS observes radiance from the surface through a spectral window at 19 microns where the atmosphere has an opacity minimum [I]. CIRS is now seeing a shift in the latitudinal distribution of temperatures froth a distinctly warmer south to a more symmetrical north -south pattern, similar to that found by Voyager IRIS [2,3] at the time of the previous vernal equinox. Near the equator the temperatures remain close to the 93.7 K value found at the surface by Huygens [4]. From the equator to the poles the temperature gradients are 2-3 K. When compared with predictions froth general circulation models [5] the measured temperatures and their seasonal changes constrain the possible types of surface material. As Cassini continues through Titan's northern spring CiRS will extend its, global coverage to took for correlations between surface temperatures and albedo and to search for diurnal temperature variations
Jennings, D. E.; Cottini, V.; Nixon, C. A.
Corneal surface temperature decreases with age.
Infrared temperature measurement has found numerous applications in the detection and diagnosis of ocular and systemic disease. In the study of ocular temperature it is important to consider all parameters which might influence recorded measurements. Examples of such parameters include room temperature, time of day and age of subject. This communication discusses the effect of age on ocular temperatures measured with a modern, wide field, colour-coded infrared detector. It is demonstrated that ocular surface temperature decreases by -0.010 degrees C per year throughout life, although the rate of change increases after middle age. PMID:16303398
Morgan, P B; Soh, M P; Efron, N
High-temperature Mars-to-Earth transfer of meteorite ALH84001
NASA Astrophysics Data System (ADS)
Martian meteorites provide crucial insights into Martian evolution and interplanetary mass transfer, including the potential for exogenesis. ALH84001 is the oldest Martian meteorite discovered so far, and has been used to derive important conclusions about Martian surface temperatures and very low-temperature Mars-to-Earth transfer. To better constrain the thermal evolution and shock metamorphic history of ALH84001, we applied (U-Th)/He thermochronometry to single grains of phosphate (merrillite) from ALH84001. The (U-Th)/He ages of individual phosphate grains in ALH84001 range from 60 Ma to 1.8 Ga, with a weighted mean of ~830 Ma. This broad age distribution reflects multiple diffusion domains, and requires a relatively high-temperature resetting event younger than � 60 Ma. These new data are combined with the published whole-rock (maskelynite as a main Ar reservoir) 40Ar/ 39Ar age spectra which show 5-8% fractional loss of radiogenic 40Ar since 4.0 Ga. He diffusion in both terrestrial and extraterrestrial apatite has a significantly higher activation energy (138 � 184 kJ/mol) than Ar diffusion in maskelynite (75 kJ/mol), leading to an important "kinetic crossover" in fractional loss contours for these systems. Taken together, the phosphate (U-Th)/He and whole-rock 40Ar/ 39Ar ages require both very low surface temperatures on Mars, and one or more short-lived, high-temperature, shock events after 4.0 Ga. We suggest that the last shock event occurred with ejection of ALH84001 from Mars, and reached a peak temperature of approximately 400 �C. These results undermine the proposed low-temperature ejection hypothesis for ALH84001, but support long-lived extremely cold Martian surface temperatures.
Min, Kyoungwon; Reiners, Peter W.
Derivation of Surface Temperature from AVHRR.
National Technical Information Service (NTIS)
The AVHRR on board NOAA satellites observes the underlying surface at different zenith angles within Theta approx. or equal +/- 68 deg. around nadir. The algorithms for retrieval of Sea Surface Temperature (SST) t(sub s) from the angle-dependent Brightnes...
A. Ignatov G. Gutman I. Dergileva
Current GISS Global Surface Temperature Analysis
We update the Goddard Institute for Space Studies (GISS) analysis of global surface temperature change. We use satellite nightlight measurements to identify measurement stations located in extreme darkness. These stations are used to adjust temperature trends of urban and peri-urban stations for non-climatic factors and to help verify that urban effects on analyzed global change are small. As the GISS
J. Hansen; R. Ruedy; M. Sato
Global trends of measured surface air temperature
We analyze surface air temperature data from available meteorological stations with principal focus on the period 1880-1985. The temperature changes at mid- and high latitude stations separated by less than 1000 km are shown to be highly correlated; at low latitudes the correlation falls off more rapidly with distance for nearby stations. We combine the station data in a way
James Hansen; Sergej Lebedeff
Satellite and surface temperature data at odds?
Based on a series of scientific papers, from Spencer and Christy (1990) to Christy and McNider (1994), a perception has been created in the popular media that satellite measurements of global temperature change are inconsistent with surface measurements and with climate model predictions of global warming rates. Such conclusions, if warranted, would be important. Global temperature change is the most
James Hansen; Helene Wilson; Makiko Sato; Reto Ruedy; Kathy Shah; Erik Hansen
A Method of Analysis of Annual Variations of Harbor Water and Earth Temperatures
In this paper, an analysis is made of the variation of ambienit temperatures of submarine and underground cable installations with respect to time and depth. A method of mathematical analysis of the initial temperature distribution is given for earth exposed to air and for earth under a relatively thick body of slowly moving water such as Baltimore Harbor. The average
W. N. McDaniel; E. F. Wolf
Surface modification of high temperature iron alloys
A method and article of manufacture of a coated iron based alloy are disclosed. The method includes providing an iron based alloy substrate, depositing a silicon containing layer on the alloy surface while maintaining the alloy at a temperature of about 700--1200 C to diffuse silicon into the alloy surface and exposing the alloy surface to an ammonia atmosphere to form a silicon/oxygen/nitrogen containing protective layer on the iron based alloy. 13 figs.
Park, J.H.
A global comparison between station air temperatures and MODIS land surface temperatures reveals the cooling role of forests
NASA Astrophysics Data System (ADS)
Most global temperature analyses are based on station air temperatures. This study presents a global analysis of the relationship between remotely sensed annual maximum LST (LSTmax) from the Aqua/Moderate Resolution Imaging Spectroradiometer (MODIS) sensor and the corresponding site-based maximum air temperature (Tamax) for every World Meteorological Organization station on Earth. The relationship is analyzed for different land cover types. We observed a strong positive correlation between LSTmax and Tamax. As temperature increases, LSTmax increases faster than Tamax and captures additional information on the concentration of thermal energy at the Earth's surface, and biophysical controls on surface temperature, such as surface roughness and transpirational cooling. For hot conditions and in nonforested cover types, LST is more closely coupled to the radiative and thermodynamic characteristics of the Earth than the air temperature (Tair). Barren areas, shrublands, grasslands, savannas, and croplands have LSTmax values between 10�C and 20�C hotter than the corresponding Tamax at higher temperatures. Forest cover types are the exception with a near 1:1 relationship between LSTmax and Tamax across the temperature range and 38�C as the approximate upper limit of LSTmax with the exception of subtropical deciduous forest types where LSTmax occurs after canopy senescence. The study shows a complex interaction between land cover and surface energy balances. This global, semiautomated annual analysis could provide a new, unique, monitoring metric for integrating land cover change and energy balance changes.
Mildrexler, David J.; Zhao, Maosheng; Running, Steven W.
High temperature langasite surface acoustic wave sensors
NASA Astrophysics Data System (ADS)
High temperature sensors are a key enabling technology for advanced control and optimization of many industry processes. This thesis reports on the development of the langasite surface acoustic wave (SAW) temperature and oxygen sensors for sensing applications in high temperature, harsh environments. The conductivity-based surface acoustic wave sensor was selected for the high temperature oxygen sensing application in this work. A series of finite element simulations of surface acoustic wave propagation in langasite SAW devices were performed to understand the effect of sensing and spacer layer on the sensor sensitivity. Langasite SAW sensors with Pt/Ti as the IDT metallization, and ZnO and SiO2 as the oxygen sensing layer and spacer layer materials, respectively, were designed, fabricated and packaged for high temperature sensing applications. Langasite SAW temperature sensors were tested successfully from room temperature up to 700 �C in wireless mode and 900 �C in wired mode. The ZnO/langasite SAW oxygen sensors were tested in wired mode and showed effective oxygen sensing response up to 700 �C. A multi-sensor with both temperature and oxygen sensing capability was also designed and tested. Understanding the input characteristic of the transducer is important when designing the SAW sensor for wireless operation. Langasite SAW device IDT transducers were characterized in frequency domain at room temperature. Conductance loss caused by the finite resistance of Pt electrode finger was observed and investigated.
Zheng, Peng
Enceladus Near-Fissure Surface Temperatures
NASA Astrophysics Data System (ADS)
Recently reported Cassini VIMS observations of thermal emission from the Enceladus south-pole fissures (Goguen et al. 2013) when combined with previous longer wavelength Cassini CIRS observations (Spencer et al. 2006) allow us to better constrain the highest temperatures present, but also require more detailed modeling of the processes which control those highest temperatures. The simplest interpretation of the VIMS observations is that the 3-5 �m thermal radiation comes from the walls within a fissure, rather than the adjacent surface. But as part of investigating that latter alternative it became clear that very high sublimation rates are implied by some predicted surface temperatures. Abramov and Spencer (2009) produced models of the expected surface temperature distribution, assuming conduction of heat through the ice, balanced by thermal radiation at the surface. However as temperature is raised, at 186K sublimation cooling equals radiation, and because it depends exponentially on temperature, it quickly dominates. We have found that including the surface sublimation cooling suppresses the higher temperatures. Regardless of the fissure temperature, surface temperatures above 200K can only be maintained by conduction within a few tens of centimeters of the assumed fissure wall. The high sublimation erosion rates (0.25 m/yr at 180K, rising to over 100 m/yr at 220K) imply that the fixed boundaries we have previously assumed are unrealistic. If these surface temperatures are maintained then either a sublimation lag of non-ice components will accumulate, inhibiting sublimation, or the geometry of the fissure vent will rapidly change. However the rate of change will be limited by the available heat provided by conduction. We are now developing numerical models with moving boundary conditions to explore the time evolution. The simplest result may be that the lip of the fissure erodes back till it no longer remains in thermal contact with the rising vapor which maintains the high fissure temperatures. Ingersoll and Pankine (2010) have explored the importance of vapor/ice equilibrium within the fissure. Those same physical principles will also control the surface temperature near the fissures.
Howell, Robert R.; Goguen, J. D.; Spencer, J. R.
Surface temperature measurement of turbine disks
NASA Astrophysics Data System (ADS)
A new method of temperature measurement with a single-wire thermocouple - slip ring system is introduced to measure the surface temperature of the turbine disks in the turbojet engines, and the accuracy of this method is considered. In this case, the limited channels of the slip ring are fully utilized and the measured surface temperatures of the disk are actual and believable enough. The problems in its application, such as the installation of the thermocouples, the cooling of the slip ring, and the balance of the turbine rotor with this system, are discussed briefly.
Wu, Hongdao; Qu, Yuwu; Li, Xungguang; Du, Shengqin
Spatial correlations of interdecadal variation in global surface temperatures
NASA Technical Reports Server (NTRS)
We have analyzed spatial correlation patterns of interdecadal global surface temperature variability from an empirical perspective. Using multitaper coherence estimates from 140-yr records, we find that correlations between hemispheres are significant at about 95 percent confidence for nonrandomness for most of the frequency band in the 0.06-0.24 cyc/yr range. Coherence estimates of pairs of 100-yr grid-point temperature data series near 5-yr period reveal teleconnection patterns consistent with known patterns of ENSO variability. Significant correlated variability is observed near 15 year period, with the dominant teleconnection pattern largely confined to the Northern Hemisphere. Peak-to-peak Delta-T is at about 0.5 deg, with simultaneous warming and cooling of discrete patches on the earth's surface. A global average of this pattern would largely cancel.
Mann, Michael E.; Park, Jeffrey
Phytoplankton physiology can affect ocean surface temperatures
NASA Astrophysics Data System (ADS)
A key biological link between ocean geochemical cycles, ocean color and sea surface temperature (SST) is the nitrogen-to-chlorophyll a (N:chl a) ratio of phytoplankton. This is because nitrogen is the limiting factor over approximately 2/3 of the ocean surface and light absorption depends on the concentration of chlorophyll a. Recent work has demonstrated systematic variability in this ratio. Using one-dimensional models at two locations we show that varying N:Chl a, rather than keeping a fixed mean value (0-150m), leads to lower chlorophyll a in the mixed layer, less light absorption within the mixed layer and cooler sea surface temperatures. At the equator the temperature reduction is 0.15�C throughout the year whereas at 35�N, a temperature difference of about 1�C occurs during the summer. Although demonstrated at only two locations, this effect is likely to occur over large parts of the ocean.
Lef�vre, Nathalie; Taylor, Arnold H.; Geider, Richard J.
A Study of Surface Temperatures, Clouds and Net Radiation
NASA Technical Reports Server (NTRS)
This study focused on the seasonal relationships and interactions of climate parameters such as the surface temperatures, net radiation, long wave flux, short wave flux, and clouds on a global basis. Five years of observations (December 1984 to November 1989) from the Earth Radiation Budget Experiment (ERBE) and the International Satellite Cloud Climatology Program (ISCCP) were used to study both seasonal variations and interannual variations by use of a basic radiation budget equation. In addition, the study was extended to include an analysis of the cloud forcing due El-Nino's impact on the ERBE parameters.
Dhuria, Harbans
Titan Surface Temperatures from Cassini RADAR Radiometry
NASA Astrophysics Data System (ADS)
The Cassini Radar instrument includes a passive microwave radiometer that operates at 13.78 GHz (2.2 cm wavelength). The radiometer is used to observe the thermal emission from Titan's surface at resolutions ranging from 5 - 500 km and at a variety of emission angles and polarizations. Nearly the entire surface has been observed through T30, enabling the construction of a mosaiced global map of the surface brightness temperature at normal incidence and the dataset now permits the separation of various contributing factors (dielectric constant and roughness/subsurface scattering as well as physical temperature). Voyager infrared measurements at 530 cm-1 show contributions of flux from the surface and near-surface atmosphere and suggested a symmetric equator-pole gradient of the of the order of 2-3K. Pure surface temperatures may be expected to show some asymmetry, with the south showing some effects of heat deposition from the long summer. Our data are much less influenced by the atmosphere and probe slightly into the subsurface. We present our preliminary results on the variation of surface temperature with latitude, and with terrain height. Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration.
Lorenz, R. D.; Janssen, M. A.; Allison, M. D.; Paganelli, F.; Kirk, R. L.; Lopes, R. M.; Wall, S. D.; Cassini RADAR Team
Observations of Lightning on Earth from the Lunar Surface
NASA Technical Reports Server (NTRS)
The NASA Optical Transient Detector (OTD) launched into a 70deg inclination orbit in April 1995 aboard the MicroLab-1 satellite and the Lightning Imaging Sensor (LIS) launched into a 35deg inclination orbit in November 1997 (and still operating today) aboard the Tropical Rainfall Measuring Mission have produced the most comprehensive global observations of lightning activity on Earth. The OTD collected data for 5-yr from an altitude of 740 km while the LIS, in its 10th year of operations, is still collecting data from its current altitude of 402 km. From these altitudes the OTD observes an individual storm within its field of view for approx.3 min and the LIS for approx.90 sec as the satellites orbit the earth. Figures 1-4 show the combined LIS/OTD distribution of lightning for day and night during the Northern Hemisphere warm season from April through August (Fig. 1,2) and the cool season from October through February (Fig. 3,4) as might be observed from the lunar surface (12-h daylight and 12-h nighttime observations). The day and night plots are for the twelve hour periods centered on local noon and midnight. The total viewtime of the global lightning activity is 200 hours or less, depending on latitude (Fig. 5). Most of the observed lightning occurs over the northern hemisphere land areas as reported in previous studies. More lightning activity is seen at the higher northern latitudes during the day. The greatest lightning maxima occurs in the southeastern US, during the day. The corresponding region at night shows much less lightning activity. In contrast, there is a maxima in lightning activity at night over the high Plains area of the U.S. This region had lower lightning rates during the daytime period. During the cold season, the southern hemisphere has significantly more lightning. The maxima in Central Africa is still present, and a secondary maxima is observed in South Africa. In South America, the maxima in Argentina occurs at night in association with large-scale mesoscale convective storm complexes. This is the region on the earth having the greatest frequency of extreme storms with flash rates exceeding 1000 flashes/min. daytime maxima is seen extending from Northern Argentina to Brazil. In the US., the Gulf of Mexico and the Gulf Coast states exhibit a maximum in lightning activity both day and night.
Goodman, S. J.; Buechler, D. E.; Christian, H. J., Jr.; Stahl, H. P.
A new model of snowball Earth; the core controlled the surface T of the Earth
NASA Astrophysics Data System (ADS)
Previous model The snowball Earth at 0.75-0.60 Ga and presumably at 2.3 Ga has been regarded as caused by decrease of greenhouse effect by atmospheric CO2. Probably not, we will show a new model. We present two new data sets to constraint the model. (1)Growth curve of continental crust by Pb-isotope age of river mouth zircon Growth rate of continental crust is highly variable depending on the geologic age; the value at 2.6-2.8Ga and 2.0-2.2Ga is maximum about 10 times more than the minimum value at 2.4-2.5Ga or 0.9-0.8Ga. The snowball time at 0.75-0.60 Ga and at 2.3 Ga never coincide with the minimum periods mentioned above, when both plate tectonic and plume activities were minimum, hence CO2-input from the mantle into atmosphere were minimum. Instead, the snowball times correspond to the periods to produce the large amounts of continental crust, e.g., the period at 0.75-0.60 Ga was a maximum during the last 1.0Ga. Another possible period of snowball at 2.3Ga does not correspond to the minimum time at 2.4-2.5Ga, but three times higher than that at minimum period. These evidences suggest that the plate tectonic movement and mantle convection during the snowball time was active enough to transport the large amounts of mantle CO2 to the surface. Nevertheless, the surface T was minimum to yield snowball glaciation. (2) Secular change of magnetic intensity Relative intensity of geomagnetic field (dipole moment) through geologic time is compared with the periods of glaciation, particularly snowball times, using the � compilation by Kono and Tanaka (1995) and Yoshihara et al. (2003). The result indicates the large variation from 25% to 150%, compared with the modern value (8 x 1022Am2), roughly speaking, every 500-1000m.y. The maximum periods are 2.5-2.4Ga, 1.1-1.4Ga and 3.5Ga, whereas minimum period was 2.8Ga, 2.3 Ga, 2.0-1.8Ga, 0.75-0.40Ga. Global glaciation seems to have occurred at periods when geomagnetic fields was lowered than 50% of today's level. A new model To explain the two new data sets, the snowball Earth model must include the mechanism to relate the increasing albedo by decreasing geomagnetic intensity. Presumably, formation of cloud can be potentially promoted by input of solar plasma due to weak geomagnetic barrier, as originally pointed out by Ney (1959). If this is correct, the surface T of the Earth was controlled by the core dynamics, rather than the greenhouse effect of atmosphere.
Maruyama, S.; Rino, S.; Yoshihara, A.
Sensitivity of surface temperature and atmospheric temperature to perturbations in the stratospheric concentration of ozone and nitrogen dioxide
NASA Technical Reports Server (NTRS)
A radiative-convective model is proposed for estimating the sensitivity of the atmospheric radiative heating rates and atmospheric and surface temperatures to perturbations in the concentration of O3 and NO2 in the stratosphere. Contribution to radiative energy transfer within the atmosphere from H2O, CO2, O3, and NO2 is considered. It is found that the net solar radiation absorbed by the earth-atmosphere system decreases with a reduction in O3; if the reduction of O3 is accompanied by an increase in NO2, there is a compensating effect due to solar absorption by NO2. The surface temperature and atmospheric temperature decrease with decreasing stratospheric O3. Another major conclusion is the strong sensitivity of surface temperature to the vertical distribution of O3 within the atmosphere. The results should be considered as reflecting the sensitivity of the proposed model rather than the sensitivity of the actual earth-atmosphere system.
Ramanathan, V.; Callis, L. B.; Boughner, R. E.
GISS Analysis of Surface Temperature Changes
NASA Technical Reports Server (NTRS)
We describe the current GISS analysis of surface temperature change based primarily on meteorological station measurements. The global surface temperature in 1998 was the warmest in the period of instrumental data. The rate of temperature change is higher in the past 25 years than at any previous time in the period of instrumental data. The warmth of 1998 is too large and pervasive to be fully accounted for by the recent El Nino, suggesting that global temperature may have moved to a higher level, analogous to the increase that occurred in the late 1970s. The warming in the United States over the past 50 years is smaller than in most of the world, and over that period there is a slight cooling trend in the Eastern United States and the neighboring Atlantic ocean. The spatial and temporal patterns of the temperature change suggest that more than one mechanism is involved in this regional cooling.
Hansen, J.; Ruedy, R.; Glascoe, J.; Sato, M.
Comparison Of Land Surface Temperature Derived From MODIS And AVHRR Sensors
Sensors on board several satellites can measure the thermal infrared radiation emitted from the earth's surface. By applying specific algorithms, this data can be used to produce Land Surface Temperature (LST) maps. This data is very important in energy balance studies, climate modeling and global change studies. This paper compares LST data derived from the Advanced High Resolution Radiometer (AVHRR)
J. Atencio; R. Sanderson; M. P. Bleiweiss; R. Steiner
Amplification of Surface Temperature Trends and Variability in the Tropical Atmosphere
The month-to-month variability of tropical temperatures is larger in the troposphere than at Earth's surface. This amplification behavior is similar in a range of observations and climate model simulations and is consistent with basic theory. On multidecadal time scales, tropospheric amplification of surface warming is a robust feature of model simulations, but it occurs in only one observational data set.
B. D. Santer; T. M. L. Wigley; C. Mears; F. J. Wentz; S. A. Klein; D. J. Seidel; K. E. Taylor; P. W. Thorne; M. F. Wehner; P. J. Gleckler; J. S. Boyle; W. D. Collins; K. W. Dixon; C. Doutriaux; M. Free; Q. Fu; J. E. Hansen; G. S. Jones; R. Ruedy; J. R. Lanzante; G. A. Meehl; V. Ramaswamy; G. Russell; G. A. Schmidt
Evaluation of Split-Window Land Surface Temperature Algorithms for Generating Climate Data Records
Land surface temperature (LST) is a key indicator of the Earth's surface energy and is used in a range of hydrological, meteorological, and climatological applications. As needed for most modeling and climate analysis applications, LST products that are generated from polar-orbiting meteorological satellite sensors have spatial resolutions from several hundred meters to several kilometers and have (quasi) daily temporal resolution.
Yunyue Yu; Jeffrey L. Privette; Ana C. Pinheiro
Seasonal Changes in Titan's Surface Temperatures
NASA Technical Reports Server (NTRS)
Seasonal changes in Titan's surface brightness temperatures have been observed by Cassini in the thermal infrared. The Composite Infrared Spectrometer (CIRS) measured surface radiances at 19 micron in two time periods: one in late northern winter (Ls = 335d eg) and another centered on northern spring equinox (Ls = 0 deg). In both periods we constructed pole-to-pole maps of zonally averaged brightness temperatures corrected for effects of the atmosphere. Between late northern winter and northern spring equinox a shift occurred in the temperature distribution, characterized by a warming of approximately 0.5 K in the north and a cooling by about the same amount in the south. At equinox the polar surface temperatures were both near 91 K and the equator was 93.4 K. We measured a seasonal lag of delta Ls approximately 9 in the meridional surface temperature distribution, consistent with the post-equinox results of Voyager 1 as well as with predictions from general circulation modeling. A slightly elevated temperature is observed at 65 deg S in the relatively cloud-free zone between the mid-latitude and southern cloud regions.
Jennins, Donald E.; Cottini, V.; Nixon, C. A.; Flasar, F. M.; Kunde, V. G.; Samuelson, R. E.; Romani, P. N.; Hesman, B. E.; Carlson, R. C.; Gorius, N. J. P.; Coustenis, A.; Tokano, T.
Anthropogenic Disturbance of Element Cycles at the Earth's Surface
NASA Astrophysics Data System (ADS)
The extent to which humans are modifying Earth's surface chemistry can be quantified by comparing total anthropogenic element fluxes with their natural counterparts [1]. We determine anthropogenic mass transfer of 77 elements from mining, fossil fuel burning, biomass burning, construction activities, and human apportionment of terrestrial net primary productivity, and compared it to natural mass transfer from terrestrial and marine net primary productivity, riverine dissolved and suspended matter fluxes to the ocean, soil erosion, eolian dust, sea-salt spray, cosmic dust, volcanic emissions and - for helium - hydrodynamic escape from the Earth's atmosphere. In addition, we introduce an approach to correct for losses during industrial processing of elements belonging to geochemically coherent groups, and explicitly incorporated uncertainties of element mass fluxes through Monte Carlo simulations [2]. Our assessment indicates that anthropogenic fluxes of iridium, osmium, helium, gold, ruthenium, antimony, platinum, palladium, rhenium, rhodium and chromium are greater than the respective natural fluxes. For these elements mining is the major factor of human dominance, whereas petroleum burning strongly influence the surficial cycle of rhenium. Apart from these 11 elements there are 15 additional elements whose anthropogenic fluxes may surpass their corresponding natural fluxes. Anthropogenic fluxes of the remaining elements are smaller than their corresponding natural fluxes although a significant human influence is observed for all of them. For example, ~20% of the annual fluxes of C, N, and P can be attributed to human activities. Such disturbances, though small compared with natural fluxes, can significantly alter concentrations in near-surface reservoirs and affect ecosystems if they are sustained over time scales similar to or longer than the residence time of elements in the respective reservoir. Examples are the continuing input of CO2 to the atmosphere that has led to a 40% increase in atmospheric CO2 concentrations, and the atmospheric redistribution of reactive nitrogen and accumulation in remote ecosystems. We note that if anthropogenic contributions to soil erosion and eolian dust are considered, anthropogenic fluxes of up to 62 elements may surpass their corresponding natural fluxes. [1] Klee and Graedel (2004), Annu. Rev. Environ. Resour., 29, p. 69-107 [2] Sen and Peucker-Ehrenbrink (2012), Environ. Sci. Technol., dx.doi.org/10.1021/es301261x
Sen, I. S.; Peucker-Ehrenbrink, B.
Clear-Sky Longwave Irradiance at the Earth's Surface--Evaluation of Climate Models.
NASA Astrophysics Data System (ADS)
An evaluation of the clear-sky longwave irradiance at the earth's surface (LI) simulated in climate models and in satellite-based global datasets is presented. Algorithm-based estimates of LI, derived from global observations of column water vapor and surface (or screen air) temperature, serve as proxy `observations.' All datasets capture the broad zonal variation and seasonal behavior in LI, mainly because the behavior in column water vapor and temperature is reproduced well. Over oceans, the dependence of annual and monthly mean irradiance upon sea surface temperature (SST) closely resembles the observed behavior of column water with SST. In particular, the observed hemispheric difference in the summer minus winter column water dependence on SST is found in all models, though with varying seasonal amplitudes. The analogous behavior in the summer minus winter LI is seen in all datasets. Over land, all models have a more highly scattered dependence of LI upon surface temperature compared with the situation over the oceans. This is related to a much weaker dependence of model column water on the screen-air temperature at both monthly and annual timescales, as observed. The ability of climate models to simulate realistic LI fields depends as much on the quality of model water vapor and temperature fields as on the quality of the longwave radiation codes. In a comparison of models with observations, root-mean-square gridpoint differences in mean monthly column water and temperature are 4-6 mm (5-8 mm) and 0.5-2 K (3-4 K), respectively, over large regions of ocean (land), consistent with the intermodel differences in LI of 5-13 W m2 (15-28 W m2).
Garratt, J. R.
Ultraviolet radiation climatology of the Earth`s surface and lower atmosphere. Final report
Ultraviolet (UV) radiation is the driving force of tropospheric chemistry and is furthermore detrimental to most living tissues. A three year modeling program was carried out to characterize the UV radiation in the lower atmosphere, with the objective of development a climatology of UV biologically active radiation, and of photo-dissociation reaction rates that are key to tropospheric chemistry. A comprehensive model, the Tropospheric Ultraviolet-Visible (TUV) model, was developed and made available to the scientific community. The model incorporates updated spectroscopic data, recent advances in radiative transfer theory, and allows flexible customization for the needs of different users. The TUV model has been used in conjunction with satellite-derived measurements of total atmospheric ozone and cloud amount, to develop a global climatology of UV radiation reaching the surface of the Earth. Initial validation studies are highly encouraging, showing that model predictions agree with direct measurements to ca. 5--10% at times when environmental conditions are well known, and to 10--30% for monthly averages when local environmental conditions can only be estimated remotely from satellite-based measurements. Additional validation studies are continuing.
Madronich, S. [National Center for Atmospheric Research, Boulder, CO (United States). Atmospheric Chemistry Div.; Stamnes, K. [Univ. of Alaska, Fairbanks, AK (United States). Dept. of Physics
Hot as You Like It: Models of the Long-term Temperature History of Earth Under Different Geological Assumptions
NASA Astrophysics Data System (ADS)
The long-term temperature history of the Earth is a subject of continued, vigorous debate. Past models of the climate of early Earth that utilize paleosol contraints on carbon dioxide struggle to maintain temperatures significantly greater than 0�C. In these models, the incoming stellar radiation is much lower than today, consistent with an expectation that the Sun was significantly fainter at that time. In contrast to these models, many proxies for ancient temperatures suggest much warmer conditions. The surface of the planet seems to have been generally free of glaciers throughout this period, other than a brief glaciation at ~2.9 billion years ago and extensive glaciation at ~2.4 billion years ago. Such glacier-free conditions suggest mean surface temperatures greater than 15�C. Measurements of oxygen isotopes in phosphates are consistent with temperatures in the range of 20-30�C; and similar measurements in cherts suggest temperatures over 50�C. This sets up a paradox. Models constrained by one set of geological proxies cannot reproduce the warm temperatures consistent with another set of geological proxies. In this presentation, we explore several potential resolutions to this paradox. First, we model the early Earth under modern-day conditions, but with the lower solar luminosity expected at the time. The next simulation allows carbon dioxide concentrations to increase up to the limits provided by paleosol constraints. Next, we lower the planet's surface albedo in a manner consistent with greater ocean coverage prior to the complete growth of continents. Finally, we remove all constraints on carbon dioxide and attempt to maximize surface temperatures without any geological constraints on model parameters. This set of experiments will allow us to set up potential resolutions to the paradox, and to drive a conversation on which solutions are capable of incorporating the greatest number of geological and geochemical constraints.
Domagal-Goldman, S.; Sheldon, N. D.
Monitoring global monthly mean surface temperatures
NASA Technical Reports Server (NTRS)
The accuracy of the global surface air temperature (SST) estimates for a particular month over the past decade is assessed using all of the in situ observations available today. The sources of noise in the data, the numbers of observations, and the spatial coverage are appraised for the comparison with the climate signal, and different analyzed results are compared to determine their reproducibility. The data are further evaluated by comparing anomalies of near-global monthly mean surface temperatures with those of global satellite channel 2 microwave sounding unit temperatures for 144 months from 1979 to 1990. The results indicate that the inherent noise level in an SST observation is about 1.0 C, and this is compounded when the observation is made in regions of large temperature gradient.
Trenberth, Kevin E.; Christy, John R.; Hurrell, James W.
Radon progeny in hydrometeors at the earth's surface.
During atmospheric thermal inversions, dew and hoarfrost concentrate gamma emitting radionuclides of the short-lived (222)Rn progeny ((214)Pb and (214)Bi), causing an increase in the total natural gamma background from the ground. To highlight this phenomenon, a volcanic zone of high (222)Rn flux was studied during the winter season 2010-11. High-specific short-lived radon progeny activities up to 122 Bq g(-1) were detected in hydrometeors forming at the earth's surface (ESHs), corresponding to a mean increase of up to 17 % of the normal gamma background value. A theoretical model, depending on radon flux from soil and predicting the radon progeny concentrations in hydrometeors forming at the ESHs is presented. The comparison between model and field data shows a good correspondence. Around nuclear power plants or in nuclear facilities that use automatic NaI or CsI total gamma spectroscopy systems for monitoring radioactive contamination, hydrometeors forming at the ESHs in sites with a high radon flux could represent a relevant source of false alarms of radioactive contamination. PMID:22039270
Voltaggio, M
Distribution of UV radiation at the Earth's surface from TOMS-measured UV-backscattered radiances
Daily global maps of monthly integrated UV-erythemal irradiance (290-400 nm) at the Earth's surface are estimated using the ozone amount, cloud transmittance, aerosol amounts, and surface reflectivity from the solar UV radiation backscattered from the Earth's atmosphere as measured by the total ozone mapping spectrometer (TOMS) and independently measured values of the extraterrestrial solar irradiance. The daily irradiance values at
J. R. Herman; N. Krotkov; E. Celarier; D. Larko; G. Labow
MODIS Land Surface Temperature and Emissivity
NASA Astrophysics Data System (ADS)
Land surface temperature (LST) is a key parameter in the physics of land surface processes at regional and global scales, combining the results of all surface-�atmosphere interactions and energy fluxes between the atmosphere and the ground (Mannstein 1987; Sellers et al. 1988). The Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra and Aqua platforms produce high-quality LST products from data, which possess a number of strengths. They include global coverage, high radiometric resolution and wide dynamic ranges, accurate geolocation (Wolfe et al. 2002), and high-quality thermal infrared (TIR) calibration accuracy used in the LST retrieval (Barnes et al. 1998).
Wan, Zhengming; Li, Zhao-Liang
GISS analysis of surface temperature change
NASA Astrophysics Data System (ADS)
We describe the current GISS analysis of surface temperature change for the period 1880-1999 based primarily on meteorological station measurements. The global surface temperature in 1998 was the warmest in the period of instrumental data. The rate of temperature change was higher in the past 25 years than at any previous time in the period of instrumental data. The warmth of 1998 was too large and pervasive to be fully accounted for by the recent El Nino. Despite cooling in the first half of 1999, we suggest that the mean global temperature, averaged over 2-3 years, has moved to a higher level, analogous to the increase that occurred in the late 1970s. Warming in the United States over the past 50 years has been smaller than in most of the world, and over that period there was a slight cooling trend in the eastern United States and the neighboring Atlantic Ocean. The spatial and temporal patterns of the temperature change suggest that more than one mechanism was involved in this regional cooling. The cooling trend in the United States, which began after the 1930s and is associated with ocean temperature change patterns, began to reverse after 1979. We suggest that further warming in the United States to a level rivaling the 1930s is likely in the next decade, but reliable prediction requires better understanding of decadal oscillations of ocean temperature.
Hansen, J.; Ruedy, R.; Glascoe, J.; Sato, M.
The Breath of Planet Earth: Atmospheric Circulation. Assimilation of Surface Wind Observations
NASA Technical Reports Server (NTRS)
Differences in air pressure are a major cause of atmospheric circulation. Because heat excites the movement of atoms, warm temperatures cause, air molecules to expand. Because those molecules now occupy a larger space, the pressure that their weight exerts is decreased. Air from surrounding high-pressure areas is pushed toward the low-pressure areas, creating circulation. This process causes a major pattern of global atmosphere movement known as meridional circulation. In this form of convection, or vertical air movement, heated equatorial air rises and travels through the upper atmosphere toward higher latitudes. Air just above the equator heads toward the North Pole, and air just below the equator moves southward. This air movement fills the gap created where increased air pressure pushes down cold air. The ,cold air moves along the surface back toward the equator, replacing the air masses that rise there. Another influence on atmospheric. circulation is the Coriolis force. Because of the Earth's rotation, large-scale wind currents move in the direction of this axial spin around low-pressure areas. Wind rotates counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere. just as the Earth's rotation affects airflow, so too does its surface. In the phenomenon of orographic lifting, elevated topographic features such as mountain ranges lift air as it moves up their surface.
Atlas, Robert; Bloom, Stephen; Otterman, Joseph
Surface Temperature Observations from AVHRR in FIFE.
NASA Astrophysics Data System (ADS)
Observations of the surface radiometric temperature by the AVHRR sensor on board the NOAA-9 satellite during the First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment conducted in central Kansas during 1987 are presented. The satellite observations were corrected for atmospheric effects using a path radiance model (MODTRAN3) and radiosonde measurements. Problems with this approach include the nonsimultaneity of the soundings with the overpass and errors involved in profile measurements. For the former, soundings before and after the overpass were interpolated to the time of the overpass. For the latter, some of the errors arise from the �0.5�C uncertainty in the dry- and wet-bulb temperatures, which can produce up to a �14% relative uncertainty in the water vapor. To overcome this uncertainty, the water vapor profiles were adjusted until the channel 4 and 5 temperature differences over a large reservoir were reduced to zero. This adjusted profile was then used over the entire site. The results are compared to ground broadband temperature readings at 10 sites and to aircraft results from the thermal channel of the NS001 sensor on the C-130 aircraft. The AVHRR values were found to be 5� to 6�C warmer than the average of the ground measurements. This difference is attributed to the fact that the ground measurements were made preferentially on well-vegetated surfaces while the AVHRR integrates over the entire site, which includes many warm surfaces.
Schmugge, T. J.; Schmidt, G. M.
Global surface air temperatures: update through 1987
Data from meteorological stations show that surface air temperatures in the 1980s are the warmest in the history of instrumental records. The four warmest years on record are all in the 1980s, with the warmest years in our analysis being 1981 and 1987. The rate of warming between the mid 1960s and the present is higher than that which occurred
James Hansen; Sergej Lebedeff
High Resolution Sea Surface Temperature Field Derived.
National Technical Information Service (NTIS)
A procedure for deriving high resolution sea surface temperature field from digital AVHRR/HRPT data is described. For the purpose of reducing the processing time, only the reflective threshold or near infrared channel is used for selecting data over clear...
S. Zhou W. Chen L. Zhang
High temperature low friction surface coating
A high temperature, low friction, flexible coating for metal surfaces which are subject to rubbing contact includes a mixture of three parts graphite and one part cadmium oxide, ball milled in water for four hours, then mixed with thirty percent by weight of sodium silicate in water solution and a few drops of wetting agent. The mixture is sprayed 12--15
High temperature low friction surface coating
A high temperature, low friction, flexible coating for metal surfaces which are subject to rubbing contact includes a mixture of three parts graphite and one part cadmium oxide, ball milled in water for four hours, then mixed with thirty percent by weight of sodium silicate in water solution and a few drops of wetting agent. The mixture is sprayed 12-15
Bhushan; Bharat
Antarctic Surface Temperature and Pressure Data.
National Technical Information Service (NTIS)
This document presents monthly mean surface temperature and pressure data from 30 Antarctic stations. These data were assembled primarily from World Weather Records volumes for 1951--1960 and 1961--1979 and from Monthly Climatic Data for the World records...
P. D. Jones D. W. S. Limbert T. A. Boden
22 Years of Sea Surface Temperatures
NSDL National Science Digital Library
This NOAA visualization video on YouTube shows the seasonal variations in sea surface temperatures and ice cover for the 22 years prior to 2007 based on data collected by NOAA polar-orbiting satellites (POES). El Niño and La Niña are easily identified, as are the trends in decreasing polar sea ice.
NOAA (National Oceanic and Atmospheric Administration) Visualizations
Middle Pliocene sea surface temperature variability
Estimates of sea surface temperature (SST) based upon foraminifer, diatom, and ostracod assemblages from ocean cores reveal a warm phase of the Pliocene between about 3.3 and 3.0 Ma. Pollen records and plant megafossils, although not as well dated, show evidence for a warmer climate at about the same time. Increased greenhouse forcing and altered ocean heat transport are the
Harry J. Dowsett; Mark A. Chandler; Thomas M. Cronin; Gary S. Dwyer
Detection of Regional Surface Temperature Trends
Trends in surface temperature over the last 100, 50, and 30 yr at individual grid boxes in a 5� latitude longitude grid are compared with model estimates of the natural internal variability of these trends and with the model response to increasing greenhouse gases and sulfate aerosols. Three different climate models are used to provide estimates of the internal variability
David J. Karoly; Qigang Wu
Trends in Surface Temperature at High Latitudes
NASA Technical Reports Server (NTRS)
The earliest signal of a climate change is expected to be found in the polar regions where warming is expected to be amplified on account of ice-albedo feedbacks associated with the high reflectivity of snow and ice. Because of general inaccessibility, there is a general paucity of in situ data and hence the need to use satellite data to observe the large-scale variability and trends in surface temperature in the region. Among the most important sensors for monitoring surface temperature has been the Advanced Very High Resolution Radiometer (AVHRR) which was first launched in 1978 and has provided continuous thermal infrared data since 1981. The top of the atmosphere data are converted to surface temperature data through various schemes that accounts for the unique atmospheric and surface conditions in the polar regions. Among the highest source of error in the data is cloud masking which is made more difficult in the polar region because of similar Signatures of clouds and snow lice covered areas. The availability of many more channels in the Moderate Resolution Imaging Spectroradiometer (MODIS) launched on board Terra satellite in December 1999 and on board Aqua in May 2002 (e.g., 36 visible and infrared channels compared to 5 for AVHRR) made it possible to minimize the error. Further capabilities were introduced with the Advanced Microwave Scanning Radiometer (AMSR) which has the appropriate frequency channels for the retrieval of sea surface temperature (SST). The results of analysis of the data show an amplified warming in the Arctic region, compared with global warming. The spatial distribution of warming is, however, not uniform and during the last 3 decades, positive temperature anomalies have been most pronounced in North America, Greenland and the Arctic basin. Some regions of the Arctic such as Siberia and the Bering Sea surprisingly show moderate cooling but this may be because these regions were anomalously warm in the 1980s when the satellite record started. Also, the SST in the Arctic basin is observed to be anomalously high in 2007 when the perennial ice cover declined dramatically to its lowest extent. In the Antarctic, surface temperature trends are much more moderate with the most positive trends occurring in the Antarctic Peninsula and parts of Western Antarctica while some cooling are observed in the Antarctic Plateau and the Ross Sea. The trends in SST in the region is similar to global averages but precipitation from more evaporation may have a key role in the spatial distribution of surface temperature in the ice covered region
Comiso, Josefino C.
Potential for extreme loss in high-latitude Earth surface processes due to climate change
NASA Astrophysics Data System (ADS)
driven Earth surface processes (ESPs) govern landscape and ecosystem dynamics in high-latitude regions. However, climate change is expected to alter ESP activity at yet uncertain rate and amplitude. We examined the sensitivity of key ESPs (cryoturbation, solifluction, nivation, and palsa mires) to changing climate by modeling their distribution in regard to climate, local topography, and soil variables in northern Fennoscandia. The distributions of ESPs were then forecasted under two future time periods, 2040-2069 and 2070-2099, using ensemble modeling and three emission scenarios. Increase of 2�C in current temperature conditions caused an almost complete loss of ESPs, highlighting the extreme climatic sensitivity of high-latitude geomorphic processes. Forecasts based on three scenarios suggest a disappearance of suitable climate for studied ESPs by the end of this century. This could initiate multiple opposing feedback between land surface and atmosphere through changes in albedo, heat fluxes, and biogeochemical cycles.
Aalto, Juha; Ven�l�inen, Ari; Heikkinen, Risto K.; Luoto, Miska
Trends in surface air temperature and temperature extremes in the Great Basin during 1901-2010
NASA Astrophysics Data System (ADS)
Guoping Tang and John A. Arnone III Division of Earth and Ecosystem Sciences, Desert Research Institute, Reno, Nevada 89512, USA Abstract: We analyzed natural trends in surface air temperature and temperature extremes in the Great Basin during 1901-2010. We found that annual average daily minimum temperature increased significantly (0.9�0.2 �C) during the study period, with daily maximum temperature increasing only slightly. The asymmetric increase in daily minimum and maximum temperature resulted in daily diurnal temperature range (DTR) decreasing significantly from 1901 to 2010. Seasonally, increase in daily minimum temperature and decrease in DTR occurred in all seasons but more significantly in summer. In contrast, daily maximum temperature showed no significant trend in any season. Increases in daily minimum temperature resulted in a decrease in the number of frost days (0.14�0.05 day yr-1) and cool nights (0.13�0.04 night yr-1) during each year from 1901 to 2010, while the number of warm nights increased significantly (0.17�0.03 night yr-1). Surprisingly, the number of warm and cool days and the length of the annual growing season showed no significant trend during the study period. None of these temporal patterns differed by elevation of the station. Thus, the results of this study suggest that continuation of these trends would lead to markedly warmer conditions in upcoming decades that may be drier than in past decades if precipitation does not increase.t;
Tang, G.; Arnone, J. A., III
Low earth orbiting Nadir Etalon Sounding Spectrometer instrument concept for temperature, moisture and trace species, LeoNESS
NASA Technical Reports Server (NTRS)
A concept for a low earth orbiting nadir etalon spectrometer sounder (LeoNESS) is described which can achieve retrieval of temperature, H2O, surface, boundary conditions, cloudiness, and trace species with an accuracy that meets or exceeds the AIRS specifications. Options employing 65-K and 30-K detectors are examined; the former may be implemented via passive radiative cooling. The concept, which is derived from the Cryogenic Limb Array Etalon Spectrometer, has the potential for improving the horizontal and vertical resolution.
Kumer, J. B.; Sterritt, L. W.; Roche, A. E.; Rosenberg, W. J.; Morrow, H. E.; Shenk, W. E.; Susskind, J.
Changes in the Annual Cycle in the Earth's Temperature
The annual cycle in temperature is massive relative to most climate variations, generally exceeding even the amplitude of glacial-interglacial temperature changes. Here we explore the spatial and temporal variability in the structure of the annual cycle using the CRU monthly gridded temperature records from 1950 to 2005, as well as a collection of individual long temperature records. The seasonal cycle
A. R. Stine; P. Huybers; I. Y. Fung
Long-term changes in net radiation at the Earth's surface: uncertainties and implications
NASA Astrophysics Data System (ADS)
Net radiation at the earth's surface plays a key role in terrestrial water, energy and carbon fluxes, but there is large uncertainty in its variation over decadal time scales. Globally, surface and satellite measurements indicate global dimming in solar radiation over many regions since the mid-20th century and then brightening over recent decades due to changes in cloudiness and aerosols. Changes in longwave radiation are driven by long-term increases in greenhouse gases and inter-annual variations in short-lived constituents such as dust and black carbon. These increases are partially offset, however, by increases in surface temperature. Current estimates of these components of the net radiation balance from satellite remote sensing are inconsistent because of inhomogeneities from changes in satellites, sensor calibration, retrieval algorithms, and so on, in addition to systematic biases. Estimates from direct ground observations are hampered by sparse spatial networks and often short-term records, and estimates based on denser networks of meteorological data are affected by errors in empirical radiation models. Some of the largest uncertainties are in the characterization of the global distribution and temporal changes in surface shortwave albedo and infrared emissivity, especially in regions with seasonal and patchy snow cover. This paper presents comparisons of legacy satellite-derived datasets (e.g. ISCCP, GEWEX/SRB) and recently developed datasets based on updated algorithms and homogenized data sources (e.g. NASA Princeton-Measures, HIRS) in the context of long-term changes in the net radiation balance at the earth's surface. We compare these with ground observations and empirical estimates based on meteorological data from in-situ sources and reanalysis. In particular we focus on the uncertainties in the magnitude and variation in surface albedo and emissivity, and their contribution to uncertainties in net radiation. We discuss the implications of these uncertainties on estimates of long-term changes in the terrestrial water cycle and trends in drought severity.
Sheffield, Justin; Coccia, Gabriele; Siemann, Amanda; Wood, Eric
Amplification of surface temperature trends and variability in thetropical atmosphere
The month-to-month variability of tropical temperatures is larger in the troposphere than at the Earth's surface. This amplification behavior is similar in a range of observations and climate model simulations, and is consistent with basic theory. On multi-decadal timescales, tropospheric amplification of surface warming is a robust feature of model simulations, but occurs in only one observational dataset. Other observations show weak or even negative amplification. These results suggest that either different physical mechanisms control amplification processes on monthly and decadal timescales, and models fail to capture such behavior, or (more plausibly) that residual errors in several observational datasets used here affect their representation of long-term trends.
Santer, B.D.; Wigley, T.M.L.; Mears, C.; Wentz, F.J.; Klein,S.A.; Seidel, D.J.; Taylor, K.E.; Thorne, P.W.; Wehner, M.F.; Gleckler,P.J.; Boyle, J.S.; Collins, W.D.; Dixon, K.W.; Doutriaux, C.; Free, M.; Fu, Q.; Hansen, J.E.; Jones, G.S.; Ruedy, R.; Karl, T.R.; Lanzante, J.R.; Meehl, G.A.; Ramaswamy, V.; Russell, G.; Schmidt, G.A.
Gravitational large bolides influence on the Earth's surface
NASA Astrophysics Data System (ADS)
The authors consider the zones of elongate negative gravity anomalies that accompany some astroblemes and conclude that the formation of such "tails" associated with the energy influence of the asteroids. After analyzing the morphological elements of Popigai crater and concluding that the ballistic trajectory of Popigai cosmic body (CB) had orientation from SE to NW [1], the authors found that this direction corresponds to the position of the linear zone of negative gravity anomalies [2]. Earlier, in the analysis of this zone with using a gravity model EGM08, Czech researchers concluded that it was formed by the fall of three satellites of Popigai CB. However, traces of large impact events here are unknown and unlikely to be detected. Earlier analysis of the Russian Gravity maps 2010, scale 1:2500,000 [2], showed the presence of gravity tails for all large craters (D ? 15 km) produced by bodies for which we can assume a trajectory with a relatively low angle to the Earth's surface. However, the proven structures of large diameter are quite few in Russia. That is why it is important to check this pattern on a global scale. Indeed, the gravity imprints of CB trajectories show up in the new shaded model of "Global marine gravity" [3] for hundreds of astroblemes not specified in [2]. The data obtained can be an additional basis for definition of the CB trajectory direction along with other morphological elements of astroblemes considered by the authors earlier [4]. Furthermore, gravity can be useful to prove the impact origin of many less certain structures, such as submerged structures. Visual observation of submerged craters is difficult, and analysis of geophysical evidence in this case is simpler than the analysis of morphology. The surface gravity anomalies mimic round shape of craters and it can be assigned to the impact category in the presence of tails, even if in the absence of data, which can reveal rootless anomalies. Question "what are the linear tail zones of negative gravity anomalies and how were they formed" is waiting for his answer. Taking into account the often-observed bends of tail-shaped depressions, a more likely explanation would be in terms of gradual destruction of the body on its way through the atmosphere. As a result, there forms a chain of smaller fragments and particles after the body (the tail), which impacts a longer area of land. References 1. Khazanovitch-Wulff K.K., Mikheeva A.V. and Kuznetsov V.F. Structural elements of some astroblemes indicating directions of cosmic body trajectories // New Concepts in Global Tectonics JOURNAL, Volume 1, Number 3, p.11-19. September 2013. www.ncgt.org 2. Khazanovitch-Wulff K. K. and Mikheeva A. V. Negative gravity anomalies as the tails of astroblemes // NCGT Journal, v. 1, no. 2, p.4-15. June 2013. www.ncgt.org 3. Sandwell D.T., Smith W. H. F. Global marine gravity from retracked Geosat and ERS-1 altimetry: Ridge segmentation versus spreading rate. J. Geophys. Res., 2009. V.114, B01411. 4. Mikheeva A.V. The complete catalog of the Earth's impact structures - 2013. URL: labmpg.sscc.ru/impact/index1.html.
Mikheeva, Anna; Khazanovitch-Wulff, Konstantin
Prediction of the speciation of alkaline earths adsorbed on mineral surfaces in salt solutions
NASA Astrophysics Data System (ADS)
Despite the fact that the bulk compositions of most low temperature natural surface waters, groundwaters, and porewaters are heavily influenced by alkaline earths, an understanding of the development of proton surface charge in the presence of alkaline earth adsorption on the surfaces of minerals is lacking. In particular, models of speciation at the mineral-water interface in systems involving alkaline earths need to be established for a range of different minerals. In the present study, X-ray standing wave results for Sr 2+ adsorption on rutile as a tetranuclear complex [Fenter, P., Cheng, L., Rihs, S., Machesky, M., Bedyzk, M.D., Sturchio, N.C., 2000. Electrical double-layer structure at the rutile-water interface as observed in situ with small-period X-ray standing waves. J. Colloid Interface Sci.225, 154-165] are used as constraints for all the alkaline earths in surface complexation simulations of proton surface charge, metal adsorption, and electrokinetic experiments referring to wide ranges of pH, ionic strength, surface coverage, and type of oxide. The tetranuclear reaction 4>SOH+M+H2O=(>SOH)2(>SO-)2_M(OH)++3H+ predominates for the large cations Sr 2+ and Ba 2+ (and presumably Ra 2+), consistent with X-ray results. In contrast, the mononuclear reaction >SOH+M+H2O=>SO-_M(OH)++2H+ predominates for the much smaller Mg 2+ (and presumably Be 2+), with minor amounts of the tetranuclear reaction. Both reaction types appear to be important for the intermediate size Ca 2+. For all the alkaline earths on all oxides, the proportions of the different reaction types vary systematically as a function of pH, ionic strength, and surface coverage. The application of Born solvation and crystal-chemical theory enables estimation of the equilibrium constants of adsorption of all the alkaline earths on all oxides. On high dielectric constant solids (rutile, magnetite, manganese dioxide), where the solvation contribution is negligable, ion adsorption correlates with crystal radius: the equilibrium constants increase in the sequence Be 2+ < Mg 2+ < Ca 2+ < Sr 2+ < Ba 2+ < Ra 2+. On low dielectric constant solids (hematite, gibbsite,and silicas), the solvation contribution opposing adsorption is largest for ions with the smallest hydrated radii: the equilibrium constants increase in the sequence Ra 2+ < Ba 2+ < Sr 2+ < Ca 2+ < Mg 2+ < Be 2+. These predicted sequences are consistent with adsorption affinities in the literature. In combination with previously published results, the present study enables the predictive use of the triple-layer model for 1:1 and 2:1 electrolytes, and mixtures of these, permitting calculation of proton surface charge and adsorption under conditions more relevent to natural water compositions than previously possible.
Sverjensky, Dimitri A.
The sea surface temperature product algorithm of the Ocean Color and Temperature Scanner (OCTS) and its accuracy
The Ocean Color and Temperature Scanner (OCTS) aboard the Advanced Earth Observing Satellite (ADEOS) can observe ocean color\\u000a and sea surface temperature (SST) simultaneously. This paper explains the algorithm for the OCTS SST product in the NASDA\\u000a OCTS mission. In the development of the latest, third version (V3) algorithm, the OCTS match-up dataset plays an important\\u000a role, especially when the
Futoki Sakaida; Masao Moriyama; Hiroshi Murakami; Hiromi Oaku; Yasushi Mitomi; Akira Mukaida; Hiroshi Kawamura
Influence of the atmospheric surface layer on the penetration of the electric field from the earth's surface into the ionosphere
NASA Astrophysics Data System (ADS)
In the used model, the quasistationary electric field in the atmosphere of the Earth is obtained by solving the conductivity equation. The penetration characteristics of the electric field from the Earth's surface into the ionosphere depend on both atmospheric and ionosphere conductivity. The ionosphere is taken into account by setting a special condition on the upper boundary of the atmosphere. The influence of the atmospheric surface layer with a reduced conductivity on the penetration of the electric field from the surface of the Earth into the ionosphere is analyzed.
Pomozov, E. V.
Effect of Temperature, Exposure Interval, and Depth of Diatomaceous Earth Treatment on Distribution, Mortality, and Progeny Production of Lesser Grain Borer (Coleoptera: Bostrichidae) in Stored Wheat
Diatomaceous earth (DE) can be used as a surface treatment in stored wheat Triticum aestivum (L.) to control pest infestations. However, it is not known how the thickness of the DE-treated wheat layer or grain temperature impact effectiveness. Therefore, we conducted an experiment in growth chambers to assess the effect of different surface layers of hard winter wheat combined with
E. A. Vardeman; F. H. Arthur; J. R. Nechols; J. F. Campbell
Calculating the temperature dependence of the specific heat for rare-earth arsenates
NASA Astrophysics Data System (ADS)
Equations have been derived for the temperature dependence of the specific heat for 14 rare-earth arsenates. The standard specific heats of some of them have also been calculated by Debye's and Ivanova's methods.
Sharipova, Z. M.; Kasenov, B. K.
Fitting the observed changes of global surface temperatures
NASA Astrophysics Data System (ADS)
The quality of the fit of a trivial or, conversely, delicately-designed model to the observed natural phenomena is the fundamental pillar stone of any forecasting, including forecasting of the Earth's Climate. Using precise mathematical and logical systems outside their range of applicability can be scientifically groundless, unwise, and even dangerous. The temperature data sets are naturally in the basis of any hypothesizing on variability and forecasting the Earth's Climate. Leaving open the question of the global temperature definitions and their determination (T), we have analyzed hemispheric and global monthly temperature anomaly series produced by the Climate Research Unit of the University of East Anglia (CRUTEM4 database) and more recently by the Berkeley Earth Surface Temperature consortium (BEST database). We first fit the data in 1850-2010 with polynomials of degrees 1 to 9 and compare it with exponential fit by the adjusted R-squared criterion that takes into consideration the number of free parameters of the model. In all the cases considered, the adjusted R-squared values for polynomials are larger than for the exponential as soon as the degree exceeds 1 or 2. The polynomial fits become even more satisfactory as soon as degree 5 or 6 is reached. Extrapolations of these trends outside of the data domain show quick divergence. For example, the CRUTEM4vNH fit in the decade 2010-2020, for degrees 2 to 5, rises steeply then, for degrees 6 to 9, reverses to steep decreasing: the reversal in extrapolated trends arises from improved ability to fit the observed "~60-yr" wave in 150 years of data prior to 2010. The extrapolations prior to 1850 are even more erratic, linked with the increased dispersion of the early data. When focusing the analysis of fits on 1900-2010 we find that the apparent oscillations of T can be modeled by a series of linear segments: An optimal fit suggests 4 slope breaks indicating two clear transitions in 1940 and 1975, and two that are less certain in 1905 and 2005. Interestingly, the Pacific Decadal Oscillation index underwent major changes around 1940-1950 and 1974-1984, i.e. the time of the breaks in slope of the T curve, suggesting a good correlation at the multi-decadal scale between the derivatives of T and PDO index. Therefore, one may speculate that the Earth's climate system may have entered a new multi-decadal regime in the last years of the 20th century and we should expect global temperature to remain constant or decrease slightly while the PDO index remains dominantly negative up to about 2030.
Courtillot, V.; Le Mou�l, J.; Kossobokov, V. G.; Gibert, D.; Lopes, F.
Radiative Forcing - Measured at Earth's Surface - Corroborate the Increasing Greenhouse Effect
NASA Astrophysics Data System (ADS)
The Intergovernmental Panel of Climate Change (IPCC) confirmed concentrations of atmospheric greenhouse gases and radiative forcing to increase as a result of human activities. Nevertheless, changes in radiative forcing related to increasing greenhouse gas concentrations could not be detected with instrumental measurements at Earth's surface so far. Here we show that atmospheric longwave downward radiation significantly increased (+5.2 Wm-2) partly due to increased cloud amount (+1.0 Wm-2), while solar shortwave radiation decreased (-2.0 Wm-2) over eight years of measurements at eight radiation stations distributed over the central Alps. With cloud effects subtracted, GCM model calculations show the cloud-free longwave flux increase (+4.2 Wm-2) to be in due proportion to the increase of temperature (+ 0.82oC) and absolute humidity (+0.21 g m-3), but to be three times larger than expected from anthropogenic greenhouse gases. The unexpected large increase of temperature and radiation fluxes was first thought being related to rising warm air advection under strengthened NAO conditions. However, recent investigations, which include measurements of 2003, show increased warming rather during summer time and no correlation with NAO. High correlation instead is found between temperature increases and the steady increase of total surface absorbed radiation, indicating that the fast temperature increase in central Europe is driven by a rapid increase of the greenhouse effect.
Philipona, R.; Duerr, B.; Marty, C.; Ohmura, A.; Wild, M.
Geomagnetic effects on the average surface temperature
NASA Astrophysics Data System (ADS)
Several results have previously shown as the solar activity can be related to the cloudiness and the surface solar radiation intensity (Svensmark and Friis-Christensen, J. Atmos. Sol. Terr. Phys., 59, 1225, 1997; Veretenenkoand Pudovkin, J. Atmos. Sol. Terr. Phys., 61, 521, 1999). Here, the possible relationships between the averaged surface temperature and the solar wind parameters or geomagnetic activity indices are investigated. The temperature data used are the monthly SST maps (generated at RAL and available from the related ESRIN/ESA database) that represent the averaged surface temperature with a spatial resolution of 0.5�x0.5� and cover the entire globe. The interplanetary data and the geomagnetic data are from the USA National Space Science Data Center. The time interval considered is 1995-2000. Specifically, possible associations and/or correlations of the average temperature with the interplanetary magnetic field Bz component and with the Kp index are considered and differentiated taking into account separate geographic and geomagnetic planetary regions.
Ballatore, P.
Temperature Dependence of Resistivity of Sintered Rare-Earth Permanent-Magnet Materials
We studied the resistivity of rare-earth permanent-magnet materials over the temperature range -40�C to +150�C. We investigated three different materials from four manufacturers, including Nd2 Fe14 B, SmCo5 , and Sm2 Co17 , and measured their resistivities and temperature coefficients. We found that rare-earth permanent-magnet materials show an anisotropic resistivity behavior. In fact, the resistivity anisotropy causes larger resistivity difference
Sami Ruoho; Minna Haavisto; Eelis Takala; Timo Santa-Nokki; Martti Paju
Data fusion with artificial neural networks (ANN) for classification of earth surface from microwave satellite measurements
NASA Technical Reports Server (NTRS)
A data fusion system with artificial neural networks (ANN) is used for fast and accurate classification of five earth surface conditions and surface changes, based on seven SSMI multichannel microwave satellite measurements. The measurements include brightness temperatures at 19, 22, 37, and 85 GHz at both H and V polarizations (only V at 22 GHz). The seven channel measurements are processed through a convolution computation such that all measurements are located at same grid. Five surface classes including non-scattering surface, precipitation over land, over ocean, snow, and desert are identified from ground-truth observations. The system processes sensory data in three consecutive phases: (1) pre-processing to extract feature vectors and enhance separability among detected classes; (2) preliminary classification of Earth surface patterns using two separate and parallely acting classifiers: back-propagation neural network and binary decision tree classifiers; and (3) data fusion of results from preliminary classifiers to obtain the optimal performance in overall classification. Both the binary decision tree classifier and the fusion processing centers are implemented by neural network architectures. The fusion system configuration is a hierarchical neural network architecture, in which each functional neural net will handle different processing phases in a pipelined fashion. There is a total of around 13,500 samples for this analysis, of which 4 percent are used as the training set and 96 percent as the testing set. After training, this classification system is able to bring up the detection accuracy to 94 percent compared with 88 percent for back-propagation artificial neural networks and 80 percent for binary decision tree classifiers. The neural network data fusion classification is currently under progress to be integrated in an image processing system at NOAA and to be implemented in a prototype of a massively parallel and dynamically reconfigurable Modular Neural Ring (MNR).
Lure, Y. M. Fleming; Grody, Norman C.; Chiou, Y. S. Peter; Yeh, H. Y. Michael
Transport of radon and thoron at the earth`s surface. Progress report, 1 January 1991--1 January 1992
This report covers progress under the current funding period Jan. 1, 1991 to Jan. 1, 1992 and presents the continuation proposal for Jan. 1, 1992 to Jan. 1, 1993. The previous progress report was submitted in May 1990, so activities during the last half of 1990 will also be included. Major activities over the last year have centered on the study of disequilibrium of radon progeny near the earth`s surface and the sources of thoron in indoor air. In addition, we have carried out supplemental measurements of radon sorption coefficients in porous materials focusing on the physical mechanism of sorption.
Schery, S.D.
Modelling the rheology of MgO under Earth's mantle pressure, temperature and strain rates.
Plate tectonics, which shapes the surface of Earth, is the result of solid-state convection in Earth's mantle over billions of years. Simply driven by buoyancy forces, mantle convection is complicated by the nature of the convecting materials, which are not fluids but polycrystalline rocks. Crystalline materials can flow as the result of the motion of defects--point defects, dislocations, grain boundaries and so on. Reproducing in the laboratory the extreme deformation conditions of the mantle is extremely challenging. In particular, experimental strain rates are at least six orders of magnitude larger than in nature. Here we show that the rheology of MgO at the pressure, temperature and strain rates of the mantle is accessible by multiscale numerical modelling starting from first principles and with no adjustable parameters. Our results demonstrate that extremely low strain rates counteract the influence of pressure. In the mantle, MgO deforms in the athermal regime and this leads to a very weak phase. It is only in the lowermost lower mantle that the pressure effect could dominate and that, under the influence of lattice friction, a viscosity of the order of 10(21)-10(22) pascal seconds can be defined for MgO. PMID:22237109
Cordier, Patrick; Amodeo, Jonathan; Carrez, Philippe
Applying Parallel Adaptive Methods with GeoFEST/PYRAMID to Simulate Earth Surface Crustal Dynamics
NASA Technical Reports Server (NTRS)
This viewgraph presentation reviews the use Adaptive Mesh Refinement (AMR) in simulating the Crustal Dynamics of Earth's Surface. AMR simultaneously improves solution quality, time to solution, and computer memory requirements when compared to generating/running on a globally fine mesh. The use of AMR in simulating the dynamics of the Earth's Surface is spurred by future proposed NASA missions, such as InSAR for Earth surface deformation and other measurements. These missions will require support for large-scale adaptive numerical methods using AMR to model observations. AMR was chosen because it has been successful in computation fluid dynamics for predictive simulation of complex flows around complex structures.
Norton, Charles D.; Lyzenga, Greg; Parker, Jay; Glasscoe, Margaret; Donnellan, Andrea; Li, Peggy
Five Years of Monitoring Mars' Daytime Surface Temperatures (Animation)
NASA Technical Reports Server (NTRS)[figure removed for brevity, see original site] Animation This movie shows the daytime temperature of the surface of Mars as measured by the Thermal Emission Spectrometer instrument on NASA's Mars Global Surveyor orbiter. These temperatures clearly show the growth and retreat of the martian northern and southern polar ice caps. The caps grow in winter and are composed of carbon dioxide ice with temperatures as low as minus 125 degrees Celsius (minus 195 degrees Fahrenheit). In the summer the caps retreat to relatively small areas around the poles. The movie also demonstrates the large difference in temperatures between the northern hemisphere's summer (beginning when solar longitude, or Ls, is 90 degrees) and the southern hemisphere's summer (beginning when Ls is 270 degrees). This difference is because the orbit of Mars around the Sun is more elliptical than Earth's orbit. As on Earth, a hemisphere's summer is when that hemisphere is tilted toward the Sun, but on Mars, the planet's distance from the Sun varies much more than on Earth. Mars is closest to the Sun, and therefore warmest, during the southern summer season. In northern summer, when Mars' northern hemisphere is tilted toward the Sun, the planet is farther from the Sun. Seasons on Mars are determined by the position of Mars in its orbit around the Sun. The position is measured in degrees of solar longitude (Ls) around the orbit, beginning at 0 degrees Ls at the northern spring equinox, progressing to 90 degrees Ls at the start of northern summer, 180 degrees Ls at the fall equinox, 270 degrees Ls at the start of northern winter, and finally back to 360 degrees, or 0 degrees, Ls at the spring equinox. The Thermal Emission Spectrometer is operated by a team led at Arizona State University, Tempe. Mars Global Surveyor left Earth on Nov. 7, 1996, and began orbiting Mars on Sept. 12, 1997. JPL, a division of the California Institute of Technology, Pasadena, manages Mars Global Surveyor for NASA's Science Mission Directorate, Washington.
Global surface air temperatures: Update through 1987
NASA Astrophysics Data System (ADS)
Data from meteorological stations show that surface air temperatures in the 1980s are the warmest in the history of instrumental records. The four warmest years on record are all in the 1980s, with the warmest years in our analysis being 1981 and 1987. The rate of warming between the mid 1960s and the present is higher than that which occurred in the previous period of rapid warming between the 1880s and 1940.
Hansen, James; Lebedeff, Sergej
A global monthly sea surface temperature climatology
The paper presents a new global 2 deg x 2 deg monthly sea surface temperature (SST) climatology, referred here to as the Shea-Trenberth-Reynolds (STR) climatology, which was derived by modifying a 1950-1979-based SST climatology from the Climate Analysis Center (CAC), by using data from the Comprehensive Ocean-Atmosphere Data Set to improve the SST estimates in the regions of the Kuroshio
Dennis J. Shea; Keyin E. Trenberth; Richard W. Reynolds
Global surface air temperatures - Update through 1987
NASA Technical Reports Server (NTRS)
Data from meteorological stations show that surface air temperatures in the 1980s are the warmest in the history of instrumental records. The four warmest years on record are all in the 1980s, with the warmest years in the analysis being 1981 and 1987. The rate of warming between the mid-1960s and the present is higher than that which occurrred in the previous period of rapid warming between the 1880s and 1940.
Hansen, James; Lebedeff, Sergej
Ion drift in the earth's inner plasmasphere during magnetospheric disturbances and proton temperature dynamics
NASA Astrophysics Data System (ADS)
Based on the thermal plasma measurements in the Earth�s inner plasmasphere on the INTER-BALL-2 and MAGION-5 satellites it has been indicated that the plasmaspheric ion temperature as a rule decreases during the main phase of magnetic storms; in this case the plasma density increases or remains at the level typical of undisturbed conditions. The physical mechanism by which the ion drift during a magnetic storm results in a temperature decrease is described. It is shown that the third adiabatic invariant also remains in processes with a characteristic time shorter than the period of charged particle drift around the Earth for cold equatorial plasma. The constructed model of the drift shell displacement from the Earth caused by a decrease in the magnetic field in the inner magnetosphere during the development of a magnetic storm satisfactorily describes the decrease in the proton temperature near the equatorial plane.
Verigin, M. I.; Kotova, G. A.; Bezrukikh, V. V.; Bogdanov, V. V.; Kaisin, A. V.
High temperature low friction surface coating
A high temperature, low friction, flexible coating for metal surfaces which are subject to rubbing contact includes a mixture of three parts graphite and one part cadmium oxide, ball milled in water for four hours, then mixed with thirty percent by weight of sodium silicate in water solution and a few drops of wetting agent. The mixture is sprayed 12-15 microns thick onto an electro-etched metal surface and air dried for thirty minutes, then baked for two hours at 65.degree. C. to remove the water and wetting agent, and baked for an additional eight hours at about 150.degree. C. to produce the optimum bond with the metal surface. The coating is afterwards burnished to a thickness of about 7-10 microns.
Bhushan, Bharat (Watervliet, NY)
Earth's surface fluid variations and deformations from GPS and GRACE in global warming
Global warming is affecting our Earth's environment. For example, sea level is rising with thermal expansion of water and fresh water input from the melting of continental ice sheets due to human-induced global warming. However, observing and modeling Earth's surface change has larger uncertainties in the changing rate and the scale and distribution of impacts due to the lack of
Shuanggen Jin; Liangjing Zhang; Guiping Feng
Connecting Atlantic temperature variability and biological cycling in two earth system models
NASA Astrophysics Data System (ADS)
Connections between the interdecadal variability in North Atlantic temperatures and biological cycling have been widely hypothesized. However, it is unclear whether such connections are due to small changes in basin-averaged temperatures indicated by the Atlantic Multidecadal Oscillation (AMO) Index, or whether both biological cycling and the AMO index are causally linked to changes in the Atlantic Meridional Overturning Circulation (AMOC). We examine interdecadal variability in the annual and month-by-month diatom biomass in two Earth System Models with the same formulations of atmospheric, land, sea ice and ocean biogeochemical dynamics but different formulations of ocean physics and thus different AMOC structures and variability. In the isopycnal-layered ESM2G, strong interdecadal changes in surface salinity associated with changes in AMOC produce spatially heterogeneous variability in convection, nutrient supply and thus diatom biomass. These changes also produce changes in ice cover, shortwave absorption and temperature and hence the AMO Index. Off West Greenland, these changes are consistent with observed changes in fisheries and support climate as a causal driver. In the level-coordinate ESM2M, nutrient supply is much higher and interdecadal changes in diatom biomass are much smaller in amplitude and not strongly linked to the AMO index.
Gnanadesikan, Anand; Dunne, John P.; Msadek, Rym
Influence of rare-earth metals on the high-temperature strength of Ni 3 Al-based alloys
The influence of the content of reaction- and surface-active alloying elements (rare-earth metals (REMs)) and the method of\\u000a their introduction into cast high-temperature ??-Ni3Al-based intermetallic alloys, which are thermally stable natural eutectic composites, on their structure-phase state and\\u000a the mechanical properties is studied. The life of low-alloy heterophase ?? + ? cast high-temperature light Ni3Al-based alloys is shown can be
K. B. Povarova; N. K. Kazanskaya; A. A. Drozdov; O. A. Bazyleva; M. V. Kostina; A. V. Antonova; A. E. Morozov
Development and evaluation of an Earth System Model with surface gravity waves
NASA Astrophysics Data System (ADS)
The critical role of oceanic surface waves in climate system is attracting more and more attention. We set up an Earth System Model, which is named as the First Institute of Oceanography-Earth System Model (FIO-ESM), composed of a coupled physical climate model and a coupled carbon cycle model. A surface wave model is introduced through including the nonbreaking wave-induced vertical mixing, which can improve the performance of climate model especially in the simulation of upper ocean mixed layer depth in the southern ocean, into the ocean general circulation model. The FIO-ESM is employed to conduct Coupled Model Intercomparison Project Phase 5 (CMIP5) experiments. The historical simulation of FIO-ESM's physical climate model for 1850-2005 shows that the simulated patterns of surface air temperature (SAT), rainfall, and El Ni�o-Southern Oscillation (ENSO) match those of the observations. Future projections under the four scenarios of RCP2.6, RCP4.5, RCP6.0, and RCP8.5 are also conducted and the global averaged SAT in 2100 would be -0.007�C, 1.10�C, 1.85�C, and 3.92�C higher than that in 2005, respectively. The historical simulation and future projection under RCP8.5 with global carbon cycle show the SAT and atmospheric CO2 concentration are well reproduced in the historical period and the global averaged SAT would increase by 3.90�C in 2100, which is quite similar to the physical climate model's result. Further analysis shows surface wave makes projected SAT in RCP2.6 about 2�C cooler in the Arctic area and 2�C warmer in the southern ocean.
Qiao, Fangli; Song, Zhenya; Bao, Ying; Song, Yajuan; Shu, Qi; Huang, Chuanjiang; Zhao, Wei
High-Temperature Sprayable Phosphor Coating Developed for Measuring Surface Temperatures
NASA Technical Reports Server (NTRS)
The use of phosphor thermography for noncontact temperature measurements in harsh environments has been proven over the last decade, but it has suffered from difficult application procedures such as vapor deposition or sputtering techniques. We have developed a high-temperature-sensitive paint that is easily applied with commercially available paint-spraying equipment and have successfully demonstrated it to temperatures up to 1500 C. Selected phosphors have also shown measurable signals to 1700 C, thus allowing a combination of phosphors to be used in high-temperature binders to make surface temperature measurements from ambient to over 1500 C. Phosphor thermography is an optical technique that measures the time response of fluorescence light, which is a function of the phosphor temperature. The phosphors are excited with short wavelength light (ultraviolet or blue), and they emit light at a longer wavelength. This technique has a benefit over other temperature measurements, such as thermocouples and infrared thermography, in difficult environments such as high blackbody backgrounds, vibration, flames, high electromagnetic noise, or where special windows may be needed. In addition, the sprayable phosphor paints easily cover large or complicated structures, providing full-surface information with a single measurement. Oak Ridge National Laboratories developed and tested the high-temperature binders and phosphors under the direction of the NASA Glenn Research Center. Refractory materials doped with rare earth metals were selected for their performance at high temperature. Survivability, adhesion, and material compatibility tests were conducted at high temperatures in a small furnace while the fluorescent response from the phosphors was being measured. A painted sample in a furnace with a clearly visible fluorescing dot excited by a pulsed laser is shown. Measuring the decay time of this fluorescence yields the surface temperature. One new paint was recently tested in a rocket test stand at Glenn. The floor of a square duct nozzle was painted, and full-field lifetime decay measurements were acquired for multiple firings of the rocket. Good agreement with predicted results was obtained, matching temperature gradients along the length of the nozzle and clearly showing shock structures. These good results were very satisfactory given that the measurements were made looking through the combustion plume. Infrared pyrometry was incapable of making the surface measurements because of the interference from the rocket exhaust, which contaminated the infrared signature.
Bencic, Timothy J.
Surface Characterization of Alkali and Alkaline Earth Metals on Single Crystal Refractory Metals
NASA Astrophysics Data System (ADS)
The experiments were conducted on the clean surfaces of W(110), Mo(110) and Nb(110) under ultrahigh vacuum conditions using techniques of line-of-sight thermal desorption mass spectrometry, Auger electron spectroscopy and retarding potential work function measurement. The clean work functions for W(110), Mo(110) and Nb(110) were found to be 5.38 eV, 5.08 eV and 4.62 eV, respectively. The behavior of the work function was characteristic of alkali and alkaline earth metal adsorption onto refractory metal surfaces with the minimum work function for the three surfaces of approximately 1.50 eV for cesium and 2.20 eV for barium. The results of the change in work function versus adsorption of cesium onto the bariated surfaces of W(110), Mo(110) and Nb(110) were similar. The energies of desorption for the different binding states were calculated for the various adsorbate-metal systems using first order desorption kinetics, that is, the adsorbates desorb at a rate linearly dependent on coverage. The desorption spectra for cesium from the various metal surfaces showed three distinct desorption sites, while barium had a more continuous decrease in activation energy of desorption up to a monolayer of coverage. The main difference between the desorption of the two adsorbates was the temperature of the terminal (lowest coverage) desorption energy site. The highest terminal desorption energy for cesium occurred on the W(110) surface at a temperature of 1200 K, while barium does not start to desorb from the W(110) surface until the temperature reaches approximately 1700 K. The temperature difference between the binding states of cesium and barium on all three of the substrates allowed for the adsorption and desorption of cesium without altering the barium adlayer. The desorption behavior of cesium from the various barium/substrate surfaces, like the work function change, was also very similar. As the coverage of pre -adsorbed barium increased, the activation energy of the cesium decreased.
Magera, Gerald Glenn
Temperature-programmed reduction of cobalt-containing catalysts of the Fischer-Tropsch synthesis based on ultrafine aluminum powders alloyed with rare-earth metals
The ultrafine aluminum powder alloyed with rare-earth metals (Ce, Sm), which is used as a support for the cobalt-containing\\u000a catalysts of the Fischer-Tropsch synthesis, was studied by the temperature-programmed reduction method. The presence of rare-earth\\u000a metals in the composition of the ultrafine aluminum powder changes the reduction process of cobalt oxides on the catalytic\\u000a system surface.
A. S. Seleznev; L. A. Petrov; V. I. Kononenko; I. A. Chupova; A. V. Ryabina
Evidence for a high temperature differentiation in a molten earth: A preliminary appraisal
NASA Technical Reports Server (NTRS)
If the earth were molten during its later stages of accretion as indicated by the present understanding of planetary accretion process, the differentiation that led to the formation of the core and mantle must have occurred at high temperatures in the range of 3000-5000 K because of the effect of pressure on the temperature of melting in the interior of the earth. This calls into question the use of low-temperature laboratory measurements of partition coefficients of trace elements to make inferences about earth accretion and differentiation. The low temperature partition coefficients cannot be directly applied to high temperature fractionations because partition coefficients refer to an equilibrium specific to a temperature for a given reaction, and must change in some proportion to exp 1/RT. There are no laboratory data on partition coefficients at the high temperatures relevant to differentiation in the interior of the earth, and an attempt to estimate high temperature distribution coefficients of siderophile elements was made by considering the chemical potential of a given element at equilibrium and how this potential changes with temperature, under some specific assumptions.
Murthy, V. Rama
NSDL National Science Digital Library
With three levels to choose from on each page - beginner, intermediate or advanced - this site provides information on our plant Earth. There is a section about water on earth and its many different varities, like freshwater, groundwater, and frozen water. There is information about the chemical make-up of water and many images showing the different water anvironments. There is a section about life in water, such as animals, plants, and plankton.
Development of practical multiband algorithms for estimating land-surface temperature from EOS/MODIS data
NASA Technical Reports Server (NTRS)
A practical multiband, hierarchical algorithm for estimating land-surface temperature from NASA's future Earth Observing System (EOS) instruments Moderate Resolution Imaging Spectroradiometer (MODIS) and Advance Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is developed through comprehensive, accurate, radiative transfer simulations at moderate spectral steps of 1-5/cm for wide ranges of atmospheric and surface conditions. The algorithm will accept empirical or estimated information about the surface emissivity and reflectivity and the atmospheric temperature and water-vapor profiles. Ground-based and aircraft measurements are necessary to validate and improve the algorithm and to establish its quality. Its accuracy depends on the calibration accuracy of thermal infrared data, uncertainties in surface heterogeneity, and temperature-dependent atmospheric absorption coefficients. Better knowledge of land-surface spectral emissivities and more accurate coefficients for atmospheric molecular band absorption and water vapor continuum absorption are needed to develop global land-surface temperature algorithms accurate to 1-2 K.
Dozier, J.; Wan, Z.
30 CFR 717.15 - Disposal of excess rock and earth materials on surface areas.
Code of Federal Regulations, 2010 CFR
Excess rock and earth materials produced from an underground mine and not disposed in underground workings or used in backfilling and grading operations shall be placed in surface disposal areas in accordance with requirements of §...
Extraterrestrial Spectral Solar Irradiance Data for Modeling Spectral Solar Irradiance at the Earth's Surface.
National Technical Information Service (NTIS)
This report describes the extraterrestrial (air mass zero, AMO) spectral solar irradiance data used by the Solar Energy Research Institute's Resource Assessment Branch in models to calculate spectral solar irradiance at the earth's surface. The report con...
C. Riordan
Thermal algorithms analysis. [programming tasks supporting the development of a thermal model of the Earth's surface
NASA Technical Reports Server (NTRS)
The programming and analysis methods to support the development of a thermal model of the Earth's surface from detailed analysis of day/night registered data sets from the Heat Capacity Mapping Mission satellite are briefly described.
Lien, T.
A nonlinear optimal estimation inverse method for radio occultation measurements of temperature, humidity, and surface pressure
An optimal estimation inverse method is presented which can be used to retrieve simultaneously vertical profiles of temperature and specific humidity, in addition to surface pressure, from satellite-to-satellite radio occultation observations of the Earth's atmosphere. The method is a nonlinear, maximum a posteriori technique which can accommodate most aspects of the real radio occultation problem and is found to be
Paul I. Palmer; J. J. Barnett; J. R. Eyre; S. B. Healy
A Spatial and Temporal Analysis of Global Sea Surface Temperature (1982-1999)
Sea surface temperature is an important indicator of the state of the earth's climate system. The aim of this research is to analyze spatial and temporal variations in global SSTs for the period of 1982-1999. There are 25 principal components which explain higher than 1% of the variance in the original 216 monthly SST anomaly images. The principal components 1,
Shaw-Wen Sheen
The Clear-Sky Greenhouse Effect Sensitivity to a Sea Surface Temperature Change
The clear-sky greenhouse effect response to a sea surface temperature (SST or Ts) change is studied using outgoing clear-sky longwave radiation measurements from the Earth Radiation Budget Experiment (ERBE). Considering geographical distributions for July 1987, the relation between the SST, the greenhouse efect G (defined as the outgoing infrared flux trapped by atmospheric gases), and the precipitable water vapor content
J. Ph. Duvel; F. M. Br�on
Relationships between tropical sea surface temperature and top-of-atmosphere radiation
To assess climate sensitivity from Earth radiation observations of limited duration and observed sea surface temperatures (SSTs) requires a closed and therefore global domain, equilibrium between the fields, and robust methods of dealing with noise. Noise arises from natural variability in the atmosphere and observational noise in precessing satellite observations. This paper explores the meaning of results that use only
Kevin E. Trenberth; John T. Fasullo; Chris O'Dell; Takmeng Wong
Modeling the rheology of MgO under pressure, temperature and strain-rate conditions of the Earth�s mantle
NASA Astrophysics Data System (ADS)
Ninety eight percent of the Earth�s volume is at temperature above 1000�C. Since the mantle is made of rocks with low thermal conductivity, the internal heat must be transported to the surface by slow convection which give rise, at the surface, to plate tectonics. Understanding and modeling the deformation mechanisms of Earth materials is thus one of the most important challenges of geophysics. Mantle convection raises however some specific questions: - What is the influence of pressure on plastic deformation ? - What is the influence of extremely low strain rates on the deformation mechanisms ? Although some very significant advances have been achieved recently on the experimental side, these questions remain largely unsolved and at the limits of our capabilities. It appears thus necessary to complement the usual experimentally-based approach by a numerical, multi-scale modeling approach in order to increase the significance of our models. This multi-scale modeling must be based on the Physics at the relevant scales and will have to be experimentally validated at these scales. Among the major phases of the deep mantle, (Mg,Fe)O is of special interest since it is the only mineral which is accessible under surface conditions (allowing the model to be validated from experimental data). The present work will focus on plastic deformation of MgO taken as a proxy for ferropericlase. Influence of pressure - The Peierls-Nabarro model provides an efficient tool to model dislocation cores and to account, through ab initio calculation of gamma-surfaces, for the influence of pressure. Plastic shear resistance increases with increasing pressure. 1/2[110]{110} shows the strongest sensitivity to pressure but remains the easiest slip system at high pressure. Influence of temperature - The thermally activated motion of a dislocation over the Peierls barrier at finite temperature is due to the nucleation of kink-pairs on the dislocation line. We start from Peierls potentials and Peierls stresses calculated previously. Kink-pair nucleation is described using an elastic-interaction model. The model describes well the temperature dependence observed for 1/2[110] glide on {110} and {100}. Influence of strain rate - The kink-pair geometry is found to be dependent on stress and strain-rate. The previous modeling allows a physically-based description of dislocation mobility at very low strain-rates. Finally, the three parameters can be combined to produce a first model of the rheology of MgO under mantle conditions.
Cordier, P.; Carrez, P.
Global trends of measured surface air temperature
NASA Astrophysics Data System (ADS)
We analyze surface air temperature data from available meteorological stations with principal focus on the period 1880-1985. The temperature changes at mid- and high latitude stations separated by less than 1000 km are shown to be highly correlated; at low latitudes the correlation falls off more rapidly with distance for nearby stations. We combine the station data in a way which is designed to provide accurate long-term variations. Error estimates are based in part on studies of how accurately the actual station distributions are able to reproduce temperature change in a global data set produced by a three-dimensional general circulation model with realistic variability. We find that meaningful global temperature change can be obtained for the past century, despite the fact that the meteorological stations are confined mainly to continental and island locations. The results indicate a global warming of about 0.5�-0.7�C in the past century, with warming of similar magnitude in both hemispheres; the northern hemisphere result is similar to that found by several other investigators. A strong warming trend between 1965 and 1980 raised the global mean temperature in 1980 and 1981 to the highest level in the period of instrumental records. The warm period in recent years differs qualitatively from the earlier warm period centered about 1940; the earlier warming was focused at high northern latitudes, while the recent warming is more global. We present selected graphs and maps of the temperature change in each of the eight latitude zones. A computer tape of the derived regional and global temperature changes is available from the authors.
Hansen, James; Lebedeff, Sergej
On the inhomogeneity of the transition surface layer of the solid core of the earth
NASA Astrophysics Data System (ADS)
Different geophysical data and conclusions of theoretical models, which can give information about the behavior of the solid and liquid cores of the Earth as well as about the existence of a transition layer as a temperature-hysteresis region at a relatively weak first-order phase transition, are compared. It is concluded that liquid inclusions inevitably exist in this region; these inclusions are involved (due to the complex convective processes occurring in the liquid core) in the transport of light materials from some areas of the solid-core surface. The porosity and permeability of the transition layer determine the seismic acoustic inhomogeneities in these areas, which contact the convective flows in the liquid core. In particular, this explains the well-known "east-west" effect. Obviously, the model of the crystalline core is not the only possible alternative for a model of a core with a metallic glasslike structure.
Pikin, S. A.
UV 380 nm reflectivity of the Earth's surface, clouds and aerosols
The 380 nm radiance measurements of the Total Ozone Mapping Spectrometer (TOMS) have been converted into a global data set of daily (1979-1992) Lambert equivalent reflectivities R of the Earth's surface and boundary layer (clouds, aerosols, surface haze, and snow\\/ice) and then corrected to RPC for the presence of partly clouded scenes. Since UV surface reflectivity is between 2 and
J. R. Herman; E. Celarier; D. Larko
Consequences of atomic oxygen interaction with silicone and silicone contamination on surfaces in low earth orbit
The exposure of silicones to atomic oxygen in low Earth orbit causes oxidation of the surface, resulting in conversion of silicone to silica. This chemical conversion increases the elastic modulus of the surface and initiates the development of a tensile strain. Ultimately, with sufficient exposure, tensile strain leads to cracking of the surface enabling the underlying unexposed silicone to be
Bruce A. Banks; Kim K. de Groh; Sharon K. Rutledge; Christy A. Haytas
The international surface temperature initiative's global land surface databank
NASA Astrophysics Data System (ADS)
The International Surface Temperature Initiative (ISTI) consists of an end-to-end process for land surface air temperature analyses. The foundation is the establishment of a global land surface Databank. This builds upon the groundbreaking efforts of scientists in the 1980s and 1990s. While using many of their principles, a primary aim is to improve aspects including data provenance, version control, openness and transparency, temporal and spatial coverage, and improved methods for merging disparate sources. The initial focus is on daily and monthly timescales. A Databank Working Group is focused on establishing Stage-0 (original observation forms) through Stage-3 data (merged dataset without quality control). More than 35 sources of data have already been added and efforts have now turned to development of the initial version of the merged dataset. Methods have been established for ensuring to the extent possible the provenance of all data from the point of observation through all intermediate steps to final archive and access. Databank submission procedures were designed to make the process of contributing data as easy as possible. All data are provided openly and without charge. We encourage the use of these data and feedback from interested users.
Lawrimore, J. H.; Rennie, J.; Gambi de Almeida, W.; Christy, J.; Flannery, M.; Gleason, B.; Klein-Tank, A.; Mhanda, A.; Ishihara, K.; Lister, D.; Menne, M. J.; Razuvaev, V.; Renom, M.; Rusticucci, M.; Tandy, J.; Thorne, P. W.; Worley, S.
Oxidation resistance of 9-12% Cr steels: effect of rare earth surface treatment
Medium Cr steels have been used in fossil fired power plants for many years because of their excellent high temperature stability and mechanical properties. The environment in a fossil fired power plant is extremely aggressive in terms of corrosion, especially oxidation. This is only accelerated as the operating temperature increases to 650C and beyond. For any new steel to be qualified for power plant use, in addition to adequate strength at the operating temperature, material wastage from all corrosion processes must be kept to a minimum acceptable level. The use of medium Cr steels provides a means to improve overall corrosion resistance. Three medium Cr are under development for use as high temperature power plant steels: 0.08C-(9-12)Cr-1.2Ni-0.7Mo-3.0Cu-3.0Co-0.5Ti. Oxidation tests were performed on the steels for times greater than 1000 hours in order to determine the oxidation kinetics and extent of material wastage. Also, rare earth oxides were incorporated into the outer surface layers of the steels to see if the oxidation resistance could be improved. These results will be compared to current power plant steels.
Dogan, Omer N.; Alman, David A.; Jablonski, Paul D.
Migration of air bubbles in ice under a temperature gradient, with application to �Snowball Earth�
To help characterize the albedo of �sea glaciers� on Snowball Earth, a study of the migration rates of air bubbles in freshwater ice under a temperature gradient was carried out in the laboratory. The migration rates of air bubbles in both natural glacier ice and laboratory-grown ice were measured for temperatures between ?36�C and ?4�C and for bubble diameters of
Ruzica Dadic; Bonnie Light; Stephen G. Warren
Low Temperature Surface Carburization of Stainless Steels
Low-temperature colossal supersaturation (LTCSS) is a novel surface hardening method for carburization of austenitic stainless steels (SS) without the precipitation of carbides. The formation of carbides is kinetically suppressed, enabling extremely high or colossal carbon supersaturation. As a result, surface carbon concentrations in excess of 12 at. % are routinely achieved. This treatment increases the surface hardness by a factor of four to five, improving resistance to wear, corrosion, and fatigue, with significant retained ductility. LTCSS is a diffusional surface hardening process that provides a uniform and conformal hardened gradient surface with no risk of delamination or peeling. The treatment retains the austenitic phase and is completely non-magnetic. In addition, because parts are treated at low temperature, they do not distort or change dimensions. During this treatment, carbon diffusion proceeds into the metal at temperatures that constrain substitutional diffusion or mobility between the metal alloy elements. Though immobilized and unable to assemble to form carbides, chromium and similar alloying elements nonetheless draw enormous amounts of carbon into their interstitial spaces. The carbon in the interstitial spaces of the alloy crystals makes the surface harder than ever achieved before by more conventional heat treating or diffusion process. The carbon solid solution manifests a Vickers hardness often exceeding 1000 HV (equivalent to 70 HRC). This project objective was to extend the LTCSS treatment to other austenitic alloys, and to quantify improvements in fatigue, corrosion, and wear resistance. Highlights from the research include the following: � Extension of the applicability of the LTCSS process to a broad range of austenitic and duplex grades of steels � Demonstration of LTCSS ability for a variety of different component shapes and sizes � Detailed microstructural characterization of LTCSS-treated samples of 316L and other alloys � Thermodynamic modeling to explain the high degree of carbon solubility possible in austenitic grades under the LTCSS process and experimental validation of model results � Corrosion testing to determine the corrosion resistance improvement possible from the LTCSS process � Erosion testing to determine the erosion resistance improvement possible from the LTCSS process � Wear testing to quantify the wear resistance improvement possible from the LTCSS process � Fatigue testing for quantifying the extent of improvement from the LTCSS process � Component treating and testing under simulated and in-line commercial operations XRD verified expanded austenite lattice, with no evidence of carbide precipitation. Carbon concentration profiles via Auger and electron dispersion spectroscopy (EDS) showed carbon levels in excess of 12 at. % in treated, type 316 SS. Scanning electron microscopy (SEM) of pulled-to-failure treated tensile specimens showed slip bands and no de-cohesion of the treated layer, verifying that the layer remains ductile. Compressive stresses in excess of 2 GPa (300 ksi) have been calculated at the surface of the case. Phase diagram (CALPHAD) (ThermoCalc) and Wagner dilute solution thermodynamic models were developed that calculate the solubility of carbon in austenite as a function of alloying content for the process time and temperature. Several commercial alloys have been modeled, and the model has been used to design experimental alloys with enhanced affinity for carbon solubility at treatment temperatures. Four experimental alloys were melted, rolled, and manufactured into test specimens, and the LTCSS treatment indicated successfully enhanced results and validated the predictions based on thermodynamic modeling. Electrochemical polarization curves show a 600 to 800 mV increase in pitting potential in treated (900-1000 mV) versus non-treated (200-300 mV) type 316 in chloride solutions. Treated 316L showed crevice-corrosion behavior similar to that of Ti-6Al-4V and Hastelloy C22. Cavitation tests showed significant increases in cavitatio
Collins, Sunniva R.; Heuer, Arthur H.; Sikka, Vinod K.
Sea surface temperature variability: patterns and mechanisms.
Patterns of sea surface temperature (SST) variability on interannual and longer timescales result from a combination of atmospheric and oceanic processes. These SST anomaly patterns may be due to intrinsic modes of atmospheric circulation variability that imprint themselves upon the SST field mainly via surface energy fluxes. Examples include SST fluctuations in the Southern Ocean associated with the Southern Annular Mode, a tripolar pattern of SST anomalies in the North Atlantic associated with the North Atlantic Oscillation, and a pan-Pacific mode known as the Pacific Decadal Oscillation (with additional contributions from oceanic processes). They may also result from coupled ocean-atmosphere interactions, such as the El Ni�o-Southern Oscillation phenomenon in the tropical Indo-Pacific, the tropical Atlantic Ni�o, and the cross-equatorial meridional modes in the tropical Pacific and Atlantic. Finally, patterns of SST variability may arise from intrinsic oceanic modes, notably the Atlantic Multidecadal Oscillation. PMID:21141660
Deser, Clara; Alexander, Michael A; Xie, Shang-Ping; Phillips, Adam S
Cylinder surface, temperature may affect LPG odorization
A study of possible odorant fade in propane by the Arthur D. Little Co. (Boston) has indicated that oxidation of interior surfaces of LPG containers may cause the odorant, ethyl mercaptan, to fade. The oxidation, ferous oxide, is a black, easily oxidizable powder that is the monoxide of iron. The study, contracted for by the Consumer Product Safety Commission (CPSC), is part of that agency's study of residential LP-gas systems. Another study is currently underway by an NLPGA task force headed by Bob Reid of Petrolane (Long Beach, Calif.). It may not be finished until the end of next year. Recently, the Propane Gas Association of Canada completed a study of odorant fade with the conclusion that much more study is needed on the subject. In addition to the cylinder surface problem, the CPSC study indicated that ambient temperatures might also affect the presence of odorant in product. This article reviews some of the results.
McWilliams, H.
Room temperature Bloch surface wave polaritons.
Polaritons are hybrid light-matter quasi-particles that have gathered a significant attention for their capability of showing room temperature and out-of-equilibrium Bose-Einstein condensation. More recently, a novel class of ultrafast optical devices have been realized by using flows of polariton fluids, such as switches, interferometers, and logical gates. However, polariton lifetimes and propagation distances are strongly limited by photon losses and accessible in-plane momenta in normal microcavity samples. In this work, we show experimental evidence of the formation of room temperature propagating polariton states arising from the strong coupling between organic excitons and a Bloch surface wave. This result, which was only recently predicted, paves the way for the realization of polariton devices that could allow lossless propagation up to macroscopic distances. PMID:24686676
Lerario, Giovanni; Cannavale, Alessandro; Ballarini, Dario; Dominici, Lorenzo; De Giorgi, Milena; Liscidini, Marco; Gerace, Dario; Sanvitto, Daniele; Gigli, Giuseppe
Low Temperature Resistivity of Yttrium-Based Alloys Containing Small Amounts of Rare Earth Metals
The resistivity of the dilute alloys of rare earth metals with yttrium has been measured at low temperatures. The result is in qualitative agreement with the recent theories due to Kondo and others on the s--d or s--f scattering. The effective s--f exchange integrals for various rare-earth solutes have been derived from the analysis of the resistivity data and compared
Tadashi Sugawara
Propane oxidative dehydrogenation over low temperature rare earth orthovanadate catalysts prepared by peroxyl method
The high purity rare earth orthovanadates were prepared by the peroxyl method, and found to be a kind of the low temperature catalysts for propane oxydehydrogenation effectively at 320 �C. The catalytic performances of LnVO4 (Ln=Y, CeYb) were much better than those of rare earth orthovanadate catalysts and also slightly exceeded that of magnesium orthovanadate Mg3(VO4)2 reported in literatures. LnVO4
Zhi Min Fang; Jing Zou; Wei Zheng Weng; Hui Lin Wan
High temperature surface protection. [10 gas turbines
NASA Technical Reports Server (NTRS)
Alloys of the MCrAlX type are the basis for high temperature surface protection systems in gas turbines. M can be one or more of Ni, Co, or Fe and X denotes a reactive metal added to enhance oxide scale adherence. The selection and formation as well as the oxidation, hot corrosion and thermal fatigue performance of MCrAlX coatings are discussed. Coatings covered range from simple aluminides formed by pack cementation to the more advanced physical vapor deposition overlay coatings and developmental plasma spray deposited thermal barrier coatings.
Levine, S. R.
A global monthly sea surface temperature climatology
The paper presents a new global 2 deg x 2 deg monthly sea surface temperature (SST) climatology, referred here to as the Shea-Trenberth-Reynolds (STR) climatology, which was derived by modifying a 1950-1979-based SST climatology from the Climate Analysis Center (CAC), by using data from the Comprehensive Ocean-Atmosphere Data Set to improve the SST estimates in the regions of the Kuroshio and the Gulf Stream. A comparison of the STR climatology with the Alexander and Mobley SST climatology showed that the STR climatology is warmer in the Northern Hemisphere, and colder poleward of 45 deg S. 22 refs.
Shea, D.J.; Trenberth, K.E.; Reynolds, R.W. (NCAR, Boulder, CO (United States) NOAA, Climate Analysis Center, Washington, DC (United States))
Sea Surface Temperature and Vegetation Index
NASA Technical Reports Server (NTRS)
This is a composite MODIS image showing the 'green wave' of spring in North America and sea surface temperature in the ocean, collected over an 8-day period during the first week in April 2000. On land, the darker green pixels show where the most green foliage is being produced due to photosynthetic activity. Yellows on land show where there is little or no productivity and red is a boundary zone. In the ocean, orange and yellows show warmer waters and blues show colder values.
A global monthly sea surface temperature climatology
NASA Technical Reports Server (NTRS)
The paper presents a new global 2 deg x 2 deg monthly sea surface temperature (SST) climatology, referred here to as the Shea-Trenberth-Reynolds (STR) climatology, which was derived by modifying a 1950-1979-based SST climatology from the Climate Analysis Center (CAC), by using data from the Comprehensive Ocean-Atmosphere Data Set to improve the SST estimates in the regions of the Kuroshio and the Gulf Stream. A comparison of the STR climatology with the Alexander and Mobley SST climatology showed that the STR climatology is warmer in the Northern Hemisphere, and colder poleward of 45 deg S.
Shea, Dennis J.; Trenberth, Kevin E.; Reynolds, Richard W.
Surface loading of aviscoelastic earthII. Spherical models
SUMMARY We apply the general theory described in Paper I to the special case of a spherically symmetric, self-gravitating, linear viscoelastic earth model. We begin by deriving equations governing the biorthogonality relations, normalization conditions and energy partitioning of the associated normal modes. Our numerical tests indicate that radially dependent pro�les of gravitational- and bulk-energy density provide a characterization of the
Jerry X. Mitrovica
Remote Sensing of Earth's Surface and Atmosphere: Interdisciplinary Scientific Commission A of the COSPAR Plenary Meeting, 29th, Washington, DC, 28 Aug. - 5 Sep., 1992
NASA Technical Reports Server (NTRS)
This conference reviewed the recent developments in remote monitoring of surface temperatures, which will be significant in future global change studies. Various techniques to derive surface temperature from existing and future remote sensing systems such as earth observing system (EOS) are discussed. Five sessions were held: (1) The nature of the problem of remote sensing of surface temperatures; (2) Surface temperature measurements from current satellites; (3) Modeling and surface observations of various techniques to measure temperature and/or emissivity, modeling of vegetation; (4) The effects of variable spectral emissivity from the determination of surface kinetic temperature using multispectral thermal infrared measurements; and (5) Future satellite systems including EOS/ASTER, EOS/MODIS-N, and EOS/AIRS.
Kahle, A. B. (editor); Njoku, E. J. (editor); Palluroni, F. D. (editor); Gillespie, A. R. (editor); Hook, S. J. (editor); Hayden, C. M. (editor); Tsuchiya, K. (editor); Dozier, J. (editor)
Diurnal Relationship Between the Surface Albedo and Surface Temperature in Revegetated Desert Ecosystems, Northwestern China
Quantification of the relationship between surface albedo and surface temperature was done by analyzing measured diurnal variations of surface albedo and surface temperature on the biological soil crusts and sand dunes within vegetation-stabilized desert ecosystems. The surface albedos and surface temperatures of sand dunes and biological soil crusts were measured concurrently over field plots of the moving sand area and
Ya-Feng Zhang; Xin-Ping Wang; Yan-Xia Pan; Rui Hu
The impact of land surface temperature on soil moisture anomaly detection from passive microwave observations
NASA Astrophysics Data System (ADS)
For several years passive microwave observations have been used to retrieve soil moisture from the Earth's surface. Low frequency observations have the most sensitivity to soil moisture, therefore the current Soil Moisture and Ocean Salinity (SMOS) and future Soil Moisture Active and Passive (SMAP) satellite missions observe the Earth's surface in the L-band frequency. In the past, several satellite sensors such as the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and WindSat have been used to retrieve surface soil moisture using multi-channel observations obtained at higher microwave frequencies. While AMSR-E and WindSat lack an L-band channel, they are able to leverage multi-channel microwave observations to estimate additional land surface parameters. In particular, the availability of Ka-band observations allows AMSR-E and WindSat to obtain coincident surface temperature estimates required for the retrieval of surface soil moisture. In contrast, SMOS and SMAP carry only a single frequency radiometer and therefore lack an instrument suited to estimate the physical temperature of the Earth. Instead, soil moisture algorithms from these new generation satellites rely on ancillary sources of surface temperature (e.g. re-analysis or near real time data from weather prediction centres). A consequence of relying on such ancillary data is the need for temporal and spatial interpolation, which may introduce uncertainties. Here, two newly-developed, large-scale soil moisture evaluation techniques, the triple collocation (TC) approach and the Rvalue data assimilation approach, are applied to quantify the global-scale impact of replacing Ka-band based surface temperature retrievals with Modern Era Retrospective-analysis for Research and Applications (MERRA) surface temperature output on the accuracy of WindSat and AMSR-E based surface soil moisture retrievals. Results demonstrate that under sparsely vegetated conditions, the use of MERRA land surface temperature instead of Ka-band radiometric land surface temperature leads to a relative decrease in skill (on average 9.7%) of soil moisture anomaly estimates. However the situation is reversed for highly vegetated conditions where soil moisture anomaly estimates show a relative increase in skill (on average 13.7%) when using MERRA land surface temperature. In addition, a pre-processing technique to shift phase of the modelled surface temperature is shown to generally enhance the value of MERRA surface temperature estimates for soil moisture retrieval. Finally, a very high correlation (R2 = 0.95) and consistency between the two evaluation techniques lends further credibility to the obtained results.
Parinussa, R. M.; Holmes, T. R. H.; Yilmaz, M. T.; Crow, W. T.
A Look at the Berkeley Earth Surface Temperature Project
NSDL National Science Digital Library
In this activity, students analyze a 2011 article by physicist Dr. Richard Muller addressing the climate change skeptic's claim that the scientific data used to support global warming is poor or unreliable. He headed a two-year study where his research team examined sources of data independently of climate scientists, and concluded that despite the imperfections in the available data sets, scientists have managed to avoid bias in data collection and correction. A student worksheet provides questions to guide the investigation. This activity is supported by a textbook chapter, What is Global Warming?, part of the unit, Climate Change, in Global Systems Science (GSS), an interdisciplinary course for high school students that emphasizes how scientists from a wide variety of fields work together to understand significant problems of global impact.
Impacts of Wind Farms on Local Land Surface Temperature
NASA Astrophysics Data System (ADS)
The U.S. wind industry has experienced a remarkably rapid expansion of capacity in recent years and this rapid growth is expected to continue in the future. While converting wind's kinetic energy into electricity, wind turbines modify surface-atmosphere exchanges and transfer of energy, momentum, mass and moisture within the atmosphere. These changes, if spatially large enough, may have noticeable impacts on local to regional weather and climate. Here we present observational evidence for such impacts based on analyses of satellite derived land surface temperature (LST) data at ~1.1 km for the period of 2003-2011 over a region in West-Central Texas, where four of the world's largest wind farms are located. Our results show a warming effect of up to 0.7 degrees C at nighttime for the 9-year period during which data was collected, over wind farms relative to nearby non wind farm regions and this warming is gradually enhanced with time, while the effect at daytime is small. The spatial pattern and magnitude of this warming effect couple very well with the geographic distribution of wind turbines and such coupling is stronger at nighttime than daytime and in summer than winter. These results suggest that the warming effect is very likely attributable to the development of wind farms. This inference is consistent with the increasing number of operational wind turbines with time during the study period, the diurnal and seasonal variations in the frequency of wind speed and direction distribution, and the changes in near-surface atmospheric boundary layer conditions due to wind farm operations. Figure 1: Nighttime land surface temperature (LST, C) differences between 2010 and 2003 (2010 minus 2003) in summer (June-July-August). Pixels with plus symbol have at least one wind turbine. A regional mean value (0.592 C) was removed to emphasize the relative LST changes at pixel level and so the resulting warming or cooling rate represents a change relative to the regional mean value. The LST data were derived from MODIS (Moderate Imaging Spectroradiometer) instruments on NASA's Aqua and Terra satellites. Note that LST measures the radiometric temperature of the Earth's surface itself - It has a larger diurnal variation than surface air temperature used in daily weather reports.
Zhou, L.; Tian, Y.; Baidya Roy, S.; Thorncroft, C.; Bosart, L. F.; Hu, Y.
Modern average global sea-surface temperature
The data contained in this data set are derived from the NOAA Advanced Very High Resolution Radiometer Multichannel Sea Surface Temperature data (AVHRR MCSST), which are obtainable from the Distributed Active Archive Center at the Jet Propulsion Laboratory (JPL) in Pasadena, Calif. The JPL tapes contain weekly images of SST from October 1981 through December 1990 in nine regions of the world ocean: North Atlantic, Eastern North Atlantic, South Atlantic, Agulhas, Indian, Southeast Pacific, Southwest Pacific, Northeast Pacific, and Northwest Pacific. This data set represents the results of calculations carried out on the NOAA data and also contains the source code of the programs that made the calculations. The objective was to derive the average sea-surface temperature of each month and week throughout the whole 10-year series, meaning, for example, that data from January of each year would be averaged together. The result is 12 monthly and 52 weekly images for each of the oceanic regions. Averaging the images in this way tends to reduce the number of grid cells that lack valid data and to suppress interannual variability.
Schweitzer, Peter N.
Imaging the earth's magnetosphere - Effects of plasma flow and temperature
NASA Technical Reports Server (NTRS)
The effects of Doppler shifting on the line centers of the magnetospheric O(+) cross section are investigated, and the resulting structure of the scattering rate as a function of bulk density is explained. Whereas the Doppler shifting frequently results in a decrease of the scattering rate, it is demonstrated that for certain drift speeds the overlap of the cross section and the solar intensity profile can lead to an increased rate, thus enhancing the relative brightness of the image above that obtained when v(p) is zero. Simulated images of the magnetosphere are obtained which are used to show quantitively how the magnetospheric image responds to variations in plasma drift speed and temperature. Changes in the brightness of the magnetospheric images also depend on the variability of the solar flux at 83.4 nm. In regions where there are plasma drifts, the brightness in the image is governed by the structure of the scattering rate, assuming a fixed temperature.
Garrido, D. E.; Smith, R. W.; Swift, D. S.; Akasofu, S.-I.
Solar variability and climate change: Geomagnetic aa index and global surface temperature
During the past ~120 years, Earth's surface temperature is correlated with both decadal averages and solar cycle minimum values of the geomagnetic aa index. The correlation with aa minimum values suggests the existence of a long-term (low-frequency) component of solar irradiance that underlies the 11-year cyclic component. Extrapolating the aa-temperature correlations to Maunder Minimum geomagnetic conditions implies that solar forcing
E. W. Cliver; V. Boriakoff; J. Feynman
Validation of the land-surface temperature products retrieved from Terra Moderate Resolution Imaging Spectroradiometer data
This paper presents the status of land-surface temperature (LST) standard products retrieved from Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS) data. Based on estimates of the channel-dependence error and noise equivalent temperature difference (NEDT) and the calibration accuracy of MODIS thermal�infrared data, the impact of instrument performance on the accuracy of LST is discussed. A double-screen scheme based
Zhengming Wan; Yulin Zhang; Qincheng Zhang; Zhao-liang Li
Observe an animation of the Coriolis effect over Earth's surface
NSDL National Science Digital Library
Find a Flash animation for the Coriolis Effect, the apparent deflection of a wind or current due to earth rotation. One animation shows a plane flying from Anchorage, Alaska toward Miami, Florida. In the second animation, a plane takes off from Tierra del Fuego toward Rio de Janeiro. In both cases, the pilots would miss their destination because the targets moved in respect to the original straight line path of the plane. For the northern hemisphere the plane would end up to the right of the target, to the left, for the southern hemisphere. The animation can be paused and rewound to stress important points.
Studio, Nasa/goddard S.; Institution, Smithsonian; National Science Foundation (NSF); Defense Advanced Research Projects Agency (DARPA); Global Change Research Project (GCRP); National Oceanic and Atmospheric Administration (NOAA)
How do Atmospheres Affect Planetary Temperatures? Activity C Can we Model an Atmosphere's Effect Upon a Planet's Surface Temperature?
NSDL National Science Digital Library
In this activity, students simulate the interaction of variables, including carbon dioxide, in a radiation balance exercise using a spreadsheet-based radiation balance model. Through a series of experiments, students attempt to mimic the surface temperatures of Earth, Mercury, Venus and Mars, and account for the influence of greenhouse gases in atmospheric temperatures. The activity supports inquiry into the real-world problem of contemporary climate change. Student-collected data is needed from activity A in the same module, "How do atmospheres interact with solar energy?" to complete this activity. Included in the resource are several student data sheets and a teacher's guide. This activity is part of module 4, "How do Atmospheres Affect Planetary Temperatures?" in Earth Climate Course: What Determines a Planet's Climate? The course aims to help students to develop an understanding of our environment as a system of human and natural processes that result in changes that occur over various space and time scales.
Relating Major Surface Processes to the Deep Earth � The Importance of the Miocene
NASA Astrophysics Data System (ADS)
Many global scale tectonic, oceanic and climate changes began in the Tertiary with global tectonics as the underlying driving force and changed the world. In full flower by the beginning of the Middle Miocene around 16 Ma, these changes continued through the Late Miocene into the present so we can firmly say that most of our modern world, continental glaciations excepted, began in the Middle and Late Miocene. We summarize in a flow diagram how the major earth surface processes active in the Miocene are related to the Deep Earth as understood by recent advances in seismic tomography. This 11 Ma interval had two global orogenic zones, the Alpine-Tethyan orogen from Gibraltar across southern Asia into Vietnam and around the Pacific Rim, both crustal expressions of downwellings taking place, especially in the upper mantle. These downwellings are balanced by upwellings in the lower mantle in and on the rim of the African and Pacific superplumes, which are large, low-shear velocity provinces; part of the rising plumes originated from the most extensively melted regions of the core-mantle boundary layer, D", where heat flow from the outer core is highest. Together these up-and downwellings indicate that mantle convection extended, at least periodically, through the whole mantle and reflected lateral variations in convection and heat flow in the cooling and slowly crystallizing outer core. Correlation of mantle convection with surface features is most evident in the uppermost mantle whose dynamic topography is readily reflected by the subsidence and tilting of continents moving toward the downwelling zones. Because they are closely synchronous, these two orogenic belts had enormous consequences for the earth's surface, and because they are close to us in time, they are easy to study and sample. Thus the Miocene is ideal to study for both its many global intra connections and for their link to the Deep Earth. As these two orogenies developed, they changed a global warm water ocean into our present cooler, more fragmented system with a cooler atmosphere. Higher plateaus and uplifted mountains deflected jet streams, expanded rain shadows promoting desertification, favored initial mountain glaciation, and helped cool air temperatures. Upwelling was enhanced on both sides of the Pacific basin, silica production shifted from the Atlantic to the Pacific and Indian Oceans, more mud and sand were brought to the ocean causing many passive margins to prograde, and hemipelagic mud became more abundant off continental margins. At the very end of the Miocene even the Mediterranean dried up, as it was isolated by the Alpine orogeny at Gibraltar. Onshore, epeirogenic uplift was widespread both in the interiors of the continents and along many of their margins. Active convergent margins changed continental tilts, completely altered some rivers, and formed new ones with new deltas, some on the other side of a continent. The above changes greatly altered the surface environment and induced many significant changes in flora and fauna and their distribution and have great economic importance. Many of the major geochemical cycles of the ocean and atmosphere also experienced major changes at this time. We posit that the generalizations ultimately emerging from the Miocene will apply to all the Phanerozoic and far back into the Precambrian and that are all tied to Deep Earth.
Potter, P. E.; Szatmari, P.
Influence of Impedance Properties of the earth's Surface on Sound Attenuation During Near-Ground Propagation
NASA Astrophysics Data System (ADS)
We consider questions of the propagation of sound waves above the Earth's surface. Formulas are given for the calculation of sound attenuation caused by the presence of the underlying surface. Different models of the impedance of the underlying surface are presented. Results of theoretical calculations of the attenuation of sound as it propagates above various types of underlying surfaces are presented. The influence of the geometry of the propagation of sound on its characteristics is analyzed.
Krasnenko, N. P.; Rakov, A. S.; Rakov, D. S.; Shamanaeva, L. G.
Satellite Sensed Skin Sea Surface Temperature
NASA Technical Reports Server (NTRS)
Quantitative predictions of spatial and temporal changes the global climate rely heavily on the use of computer models. Unfortunately, such models cannot provide the basis for climate prediction because key physical processes are inadequately treated. Consequently, fine tuning procedures are often used to optimize the fit between model output and observational data and the validation of climate models using observations is essential if model based predictions of climate change are to be treated with any degree of confidence. Satellite Sea Surface Temperature (SST) observations provide high spatial and temporal resolution data which is extremely well suited to the initialization, definition of boundary conditions and, validation of climate models. In the case of coupled ocean-atmosphere models, the SST (or more correctly the 'Skin' SST (SSST)) is a fundamental diagnostic variable to consider in the validation process. Daily global SST maps derived from satellite sensors also provide adequate data for the detection of global patterns of change which, unlike any other SST data set, repeatedly extend into the southern hemisphere extra-tropical regions. Such data are essential to the success of the spatial 'fingerprint' technique, which seeks to establish a north-south asymmetry where warming is suppressed in the high latitude Southern Ocean. Some estimates suggest that there is a greater than 80% chance of directly detecting significant change (97.5 % confidence level) after 10-12 years of consistent global observations of mean sea surface temperature. However, these latter statements should be qualified with the assumption that a negligible drift in the observing system exists and that biases between individual instruments required to derive a long term data set are small. Given that current estimates for the magnitude of global warming of 0.015 K yr(sup -1) - 0.025 K yr(sup -1), satellite SST data sets need to be both accurate and stable if such a warming trend is to be confidently detected. Some of these activities are focussed to develop and deploy instrumentation suitable for the collection of precise in situ measurements of the SSST which can be used to improve the accuracy of satellite measurements, while others develop techniques to generate improved global analyses of sea surface temperature using historical data.
Donlon, Craig
High-emittance surfaces for high-temperature space radiator applications
NASA Astrophysics Data System (ADS)
Anticipated space power systems which employ nuclear or solar dynamic power technologies may be required to reject waste heat at temperatures up to 950K. High temperature radiators will be required to have high thermal emittance surfaces which are durable to elevated temperatures as well as the operational space environment. Additional performance and durability threats such as extreme temperature variations and low earth orbital atomic oxygen impose challenging constraints upon the selection of suitable radiator surfaces. Traditional surface coatings which are acceptable for high emittance low temperature radiators may spall or degrade in an environment where large temperature changes high temperatures and atomic oxygen is present. Surface roughening and/or chemical modifications which produce high emittance surfaces that are an integral part of the radiator substrate may have much greater durability than coatings applied to radiator substrates. A variety of surface modification techniques have been evaluated for emittance enhancement of radiator surfaces. These techniques include: acid etching heat treating abrasion sputter texturing electro-chemical texturing arc texturing and atomic oxygen beam texturing. Candidate radiator surface materials investigated include: Nb-1 Zr Cu Ti Ti-6 Al-4 v 304 stainless steel Al6061-T6 Mo W and Ta. Results of durability evaluation of selected radiator surfaces in an atomic oxygen environment is also presented. 1.
Banks, Bruce A.; Miller, Sharon K.; Hotes, Deborah
Land Surface Temperature Measurements form EOS MODIS Data.
National Technical Information Service (NTIS)
We have developed a physics-based land-surface temperature (LST) algorithm for simultaneously retrieving surface band-averaged emissivities and temperatures from day/night pairs of MODIS (Moderate Resolution Imaging Spectroradiometer) data in seven therma...
Z. Wan
Three modes of interdecadal trends in sea surface temperature and sea surface height
NASA Astrophysics Data System (ADS)
It might be thought that sea surface height and sea surface temperature would be tightly related. We show that this is not necessarily the case on a global scale. We analysed this relationship in a suite of coupled climate models run under 1860 forcing conditions. The models are low-resolution variants of the GFDL Earth System Model, reported in Galbraith et al. (J. Clim. 2011). 1. Correlated changes in global sea surface height and global sea surface temperature. This mode corresponds to opening and closing of convective chimneys in the Southern Ocean. As the Southern Ocean destratifies, sea ice formation is suppressed during the winter and more heat is taken up during the summer. This mode of variability is highly correlated with changes in the top of the atmosphere radiative budget and weakly correlated with changes in the deep ocean circulation. 2. Uncorrelated changes in global sea surface height and global sea surface temperature. This mode of variability is associated with interdecadal variabliity in tropical winds. Changes in the advective flux of heat to the surface ocean play a critical role in driving these changes, which also result in significant local changes in sea level. Changes sea ice over the Southern Ocean still result in changes in solar absorption, but these are now largely cancelled by changes in outgoing longwave radiation. 3. Anticorrelated changes in global sea surface height and global sea surface temperatures. By varying the lateral diffusion coefficient in the ocean model, we are able to enhance and suppress convection in the Southern and Northern Pacific Oceans. Increasing the lateral diffusion coefficients shifts the balance sources of deep water away from the warm salty deep water of the North Atlantic and towards cold fresh deep water from the other two regions. As a result, even though the planet as a whole warms, the deep ocean cools and sea level falls, with changes of order 30 cm over 500 years. The increase in solar absorption in polar regions is more than compensated by an increase in outgoing longwave radiation. Relationship between global SSH trend over a decade and (A) local SSH change over a decade (m/m). (B) Global SST change over a decade (m/K) (C) Portion of decadal SST change correlated with net radiation at the top of the atmosphere (m/K) (D) Portion of decadal SST change not correlated with net radiation at the top of the atmosphere.
Gnanadesikan, A.; Pradal, M.
Surface temperature measurements in rolling and sliding EHD contacts
NASA Technical Reports Server (NTRS)
In this study, moving surface temperature measurements in rolling and sliding EHD point contacts were made using an available infrared technique. Film thickness and traction have also been measured. Slide-to-roll ratios of -2 to +2 have been studied. By using a different kinematic configuration, stationary surface temperatures have also been measured. It has been shown that, while surface temperature rises in the low slip region are relatively small, stationary surface temperatures are significantly higher than the moving surface temperatures. Flash temperature theory has been extended to cover the combined rolling and sliding conditions. Correlation between the predicted and the measured values has also been performed.
Nagaraj, H. S.; Sanborn, D. M.; Winer, W. O.
Effective wave tilt and surface impedance over a laterally inhomogeneous two-layer Earth
the electromagnetic fields at the surface of the Earth for a postulated downcoming plane wave. We examine the calculated change in the surface impedance and wave tilt due to lateral inhomogenei- ties. It is found that the magnetic wave tilt (H z\\/H x) is most seriously affected by such anomalies. This may have important consequences on electromagnetic probing of nonuniform
W. J. Hughes; J. R. Wait
Estimates of Faraday rotation with passive microwave polarimetry for microwave remote sensing of Earth surfaces
A technique based on microwave passive polarimetry for the estimates of ionospheric Faraday rotation for microwave remote sensing of Earth surfaces is described. Under the assumption of azimuth symmetry for the surfaces under investigation, it is possible to estimate the ionospheric Faraday rotation from the third Stokes parameter of microwave radiation. An error analysis shows that the Faraday rotation can
Simon H. Yueh
Uplifts and tilts at earth's surface induced by pressure transients from hydraulic fractures
The pressure transient that spreads through the formation during and after a hydraulic fracture treatment pressurizes the formation and induces a certain swelling. This swelling and the accompanying uplift at the earth's surface can be estimated with poroelastic theory. The uplift may produce a significant signal in tiltmeter devices placed at the surface. This paper reports six fracturing treatments in
Observations of oceanic internal and surface waves from the earth resources technology satellite
Periodic features observed on the ocean surface from the Earth Resources Technology Satellite 1 have been interpreted as surface slicks due to internal wave packets. They appear to be generated at the edge of the continental shelf by semidurnal and diurnal tidal actions and propagate shoreward. Nonlinear effects apparently distort the wave packets as they progress across the shelf. This
John R. Apel; H. Michael Byrne; John R. Proni; Robert L. Charnell
Surface Color and Effect of Temperature Change
NSDL National Science Digital Library
This activity builds the basic understanding that the heating (indicated by temperature differences) of an object is related to the object�s surface color. Materials required for this investigation include a pair of thermometers, light and dark construction paper, a heat lamp, and two foam cups and two large containers. The resource includes teaching tips and questions to guide student discussion. This is chapter 3 of Meteorology: An Educator's Resource for Inquiry-Based Learning for Grades 5-9. The guide includes a discussion of learning science, the use of inquiry in the classroom, instructions for making simple weather instruments, and more than 20 weather investigations ranging from teacher-centered to guided and open inquiry investigations.
Sea surface temperatures from VAS MSI data
NASA Technical Reports Server (NTRS)
A procedure is developed for estimating sea surface temperatures from multispectral image data acquired from the VISSR atmospheric sounder on the geostationary GOES satellites. Theoretical regression equations for two and three infrared window channels are empirically tuned using clear field of view satellite radiances matched with reports of SST from NOAA fixed environmental buoys. The empirical regression equations are then used to produce daily regional analyses of SST. Monthly mean SST's for the western North Atlantic and the eastern equatorial Pacific during March and July 1982 were produced for use in the SST Intercomparison Workshop Series. Workshop results showed VAS SST's have a scatter of 0.8-1.0 C and a slight warm bias with respect to the other measurements of SST. The VAS SST's show no discernible bias in the region of El Chichon volcanic aerosol cloud.
Bates, J. J.
Linkages between Surface Temperature and Tropospheric Ozone
NSDL National Science Digital Library
This lesson is designed to help students gain knowledge in using the MY NASA DATA Live Access Server (LAS) to obtain a microset of data, in using Excel to graph the data, then using the graphs to investigate the relationship between surface temperature and tropospheric ozone. They will also analyze changes in tropospheric ozone and then hypothesize about the consequences of these changes. The measurements are taken over Chattanooga, TN. Students are provided content-related activities to enhance background knowledge, and then are provided detailed instructions on how to download data from the MY NASA DATA Live Access Server (LAS) and to use Excel to graph the data. The lesson provides detailed procedure, related links and sample graphs, follow-up questions and extensions, and Teacher Notes.
Middle Pliocene sea surface temperature variability
Estimates of sea surface temperature (SST) based upon foraminifer, diatom, and ostracod assemblages from ocean cores reveal a warm phase of the Pliocene between about 3.3 and 3.0 Ma. Pollen records and plant megafossils, although not as well dated, show evidence for a warmer climate at about the same time. Increased greenhouse forcing and altered ocean heat transport are the leading candidates for the underlying cause of Pliocene global warmth. Despite being a period of global warmth, this interval encompasses considerable variability. Two new SST reconstructions are presented that are designed to provide a climatological error bar for warm peak phases of the Pliocene and to document the spatial distribution and magnitude of SST variability within the mid-Pliocene warm period. These data suggest long-term stability of low-latitude SST and document greater variability in regions of maximum warming. Copyright 2005 by the American Geophysical Union.
Dowsett, H. J.; Chandler, M. A.; Cronin, T. M.; Dwyer, G. S.
Downscaling of land surface temperatures from SEVIRI
NASA Astrophysics Data System (ADS)
Land surface temperature (LST) determines the radiance emitted by the surface and hence is an important boundary condition of the energy balance. In urban areas, detailed knowledge about the diurnal cycle in LST can contribute to understand the urban heat island (UHI). Although the increased surface temperatures compared to the surrounding rural areas (surface urban heat island, SUHI) have been measured by satellites and analysed for several decades, an operational SUHI monitoring is still not available due to the lack of sensors with appropriate spatiotemporal resolution. While sensors on polar orbiting satellites are still restricted to approx. 100 m spatial resolution and coarse temporal coverage (about 1-2 weeks), sensors on geostationary platforms have high temporal (several times per hour) and poor spatial resolution (>3 km). Further, all polar orbiting satellites have a similar equator crossing time and hence the SUHI can at best be observed at two times a day. A downscaling DS scheme for LST from the Spinning Enhanced Visible Infra-Red Imager (SEVIRI) sensor onboard the geostationary meteorological Meteosat 8 to spatial resolutions between 100 and 1000 m was developed and tested for Hamburg. Various data were tested as predictors, including multispectral data and derived indices, morphological parameters from interferometric SAR and multitemporal thermal data. All predictors were upscaled to the coarse resolution approximating the point spread function of SEVIRI. Then empirical relationships between the predictors and LST were derived which are then transferred to the high resolution domain, assuming they are scale invariant. For validation LST data from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and the Enhanced Thematic Mapper Plus (ETM+) for two dates were used. Aggregated parameters from multi-temporal thermal data (in particular annual cycle parameters and principal components) proved particularly suitable. The results for the highest resolution of 100 m showed a high explained variance (R^2 = 0.71) and relatively low root mean square errors (RMSE = 2.2 K) for the ASTER scene and slightly higher errors (R^2 = 0.73, RMSE = 2.53) for the ETM+ scene. A considerable percentage of the error was systematic due to the different viewing geometry of the sensors (the high resolution LST was overestimated about 1.3 K for ASTER and 0.66 K for ETM+). This shows that DS of SEVIRI LST is possible up to a resolution of 100 m for urban areas and that multitemporal thermal data are particularly suitable as predictors. Further, the scheme was used to produce an entire diurnal cycle in high resolution. While essential characteristics of the diurnal cycle were well reproduced, certain artefacts resulting from the multitemporal predictors from different seasons (like phenology and different water surface temperatures) were generated. Eventually, the bias and its dependence on the viewing geometry and topography are currently investigated.
Bechtel, B.; Zaksek, K.
Stereo techniques for 3D mapping of object surface temperatures
In this paper, we present two stereo methods to obtain 3D mappings of object surface temperatures. The first method uses a pair of trichromatic cameras to recover the 3D geometry and then maps the temperature data from a thermal camera onto the recovered surface. The second method recovers the 3D surface temperature map using a pair of thermal cameras by
Surya Prakash; Pei Yean Lean; Antonio Robles-Kelly
High-temperature electrical resistivity of rare-earth metals with variable valence
The electrical resistivity of compounds of rare-earth metals at high temperatures is calculated on the basis of allowance for the background mechanism of scattering and the hybridization of local electron states with the states of conduction electrons. An analytic expression is obtained for resistivity in a strong hybridization approximation. It follows from the expression that electrical resistivity may have a negative temperature coefficient within a broad range of high temperatures. The use of a three-band (s, d, f) model makes it possible to explain experimental data on the resistivity of certain rare-earth metals, particularly the connection between the sign of the temperature coefficient of electrical resistivity and the curvature of the relation (T).
Povzner, A.A.; Abel'skii, S.S.
High temperature radiator materials for applications in the low Earth orbital environment
Radiators must be constructed of materials which have high emittance in order to efficiently radiate heat from high temperature space power systems. In addition, if these radiators are to be used for applications in the low Earth orbital environment, they must not be detrimentally affected by exposure to atomic oxygen. Four materials selected as candidate radiator materials 304 stainless steel,
S. K. Rutledge; B. A. Banks; M. J. Mirtich; R. Lebed; J. Brady; D. Hotes; M. Kussmaul
Radiative Forcing - Measured at Earth's Surface - Corroborate the Increasing Greenhouse Effect
NASA Astrophysics Data System (ADS)
The Intergovernmental Panel of Climate Change (IPCC) confirmed concentrations of atmospheric greenhouse gases and radiative forcing to increase as a result of human activities. Nevertheless, changes in radiative forcing related to increasing greenhouse gas concentrations could not be detected with instrumental measurements at Earth's surface so far. Here we show that atmospheric longwave downward radiation significantly increased (+5.2 Wm-2) partly due to increased cloud amount (+1.0 Wm-2), while solar shortwave radiation decreased (-2.0 Wm-2) over eight years of measurements at eight radiation stations distributed over the central Alps. With cloud effects subtracted, model calculations show the cloud-free longwave flux increase (+4.2 Wm-2) to be in due proportion to the increase of temperature (+ 0.82 oC) and absolute humidity (+0.21 g m-3), but to be three times larger than expected from anthropogenic greenhouse gases, and therefore in part related to rising warm air advection under strengthened NAO conditions. However, after correcting for two thirds of the temperature and humidity rises, the increase of cloud-free longwave downward radiation (+1.8 Wm-2) remains significant and demonstrates anthropogenic greenhouse gas radiative forcing.
Philipona, R.; Duerr, B.; Marty, C.; Ohmura, A.; Wild, M.
Radiative forcing - measured at Earth's surface - corroborate the increasing greenhouse effect
NASA Astrophysics Data System (ADS)
The Intergovernmental Panel of Climate Change (IPCC) confirmed concentrations of atmospheric greenhouse gases and radiative forcing to increase as a result of human activities. Nevertheless, changes in radiative forcing related to increasing greenhouse gas concentrations could not be experimentally detected at Earth's surface so far. Here we show that atmospheric longwave downward radiation significantly increased (+5.2(2.2) Wm-2) partly due to increased cloud amount (+1.0(2.8) Wm-2) over eight years of measurements at eight radiation stations distributed over the central Alps. Model calculations show the cloud-free longwave flux increase (+4.2(1.9) Wm-2) to be in due proportion with temperature (+0.82(0.41) �C) and absolute humidity (+0.21(0.10) g m-3) increases, but three times larger than expected from anthropogenic greenhouse gases. However, after subtracting for two thirds of temperature and humidity rises, the increase of cloud-free longwave downward radiation (+1.8(0.8) Wm-2) remains statistically significant and demonstrates radiative forcing due to an enhanced greenhouse effect.
Philipona, Rolf; D�rr, Bruno; Marty, Christoph; Ohmura, Atsumu; Wild, Martin
Temperature range and conditions of stable operation of gas-discharge rare-earth metal vapor lasers
NASA Astrophysics Data System (ADS)
We have experimentally studied the temperature range and conditions of the stable operation of rare-earth metal (REM) vapor lasers. Gas-discharge tubes made of alumina (Al2O3-GDTs) were used in the experiments. The lasing appears at the temperature when the saturated-vapor pressure of REMs reaches the value of 0.1 Torr and abruptly drops at the melting temperature of corresponding REM under any excitation conditions. The necessity of protecting film of REM aluminates LnnAlmOk and oxides Ln2O3 on the inner surface of Al2O3-GDT for stable operation of these lasers is shown. An explanation of lasing impossibility in vapors of cerium (Ce), praseodymium (Pr), neodymium (Nd), gadolinium (Gd), and terbium (Tb) under gas-discharge excitation is proposed.
Gerasimov, V. A.; Gerasimov, V. V.; Pavlinskiy, A. V.
High temperature radiator materials for applications in the low Earth orbital environment
Radiators must be constructed of materials which have high emittance in order to efficiently radiate heat from high temperature space power systems. In addition, if these radiators are to be used for applications in the low Earth orbital environment, they must not be detrimentally affected by exposure to atomic oxygen. Four materials selected as candidate radiator materials 304 stainless steel, copper, titanium-6% aluminum-4% vanadium (Ti-6%Al-4%V), and niobium-1% zirconium (Nb-1%Zr) were surface modified by acid etching, heat treating, abrading, sputter texturing, electrochemical etching, and combinations of the above in order to improve their emittance. Combination treatment techniques with heat treating as the second treatment provided about a factor of two improvement in emittance for 304 stainless steel, Ti-6%Al-4%V, and Nb-1%Zr. A factor of three improvement in emittance occurred for discharge chamber sputter textured copper. Exposure to atomic oxygen in RF plasma asher did not significantly change the emittance of those samples that had been heat treated as part of their texturing process. An evaluation of oxygen penetration is needed to understand how oxidation affects the mechanical properties of these materials when heat treated.
Rutledge, S.K.; Banks, B.A.; Mirtich, M.J. [Lewis Research Center, Cleveland, OH (United States); Lebed, R. [Michigan State Univ., East Lansing, MI (United States); Brady, J.; Hotes, D.; Kussmaul, M. [Cleveland State Univ., OH (United States)
High temperature radiator materials for applications in the low Earth orbital environment
NASA Technical Reports Server (NTRS)
Radiators must be constructed of materials which have high emittance in order to efficiently radiate heat from high temperature space power systems. In addition, if these radiators are to be used for applications in the low Earth orbital environment, they must not be detrimentally affected by exposure to atomic oxygen. Four materials selected as candidate radiator materials (304 stainless steel, copper, titanium-6% aluminum-4% vanadium (Ti-6%Al-4%V), and niobium-1% zirconium (Nb-1%Zr)) were surface modified by acid etching, heat treating, abrading, sputter texturing, electrochemical etching, and combinations of the above in order to improve their emittance. Combination treatment techniques with heat treating as the second treatment provided about a factor of two improvement in emittance for 304 stainless steel, Ti-6%Al-4%V, and Nb-1%Zr. A factor of three improvement in emittance occurred for discharge chamber sputter textured copper. Exposure to atomic oxygen in an RF plasma asher did not significantly change the emittance of those samples that had been heat treated as part of their texturing process. An evaluation of oxygen penetration is needed to understand how oxidation affects the mechanical properties of these materials when heat treated.
Rutledge, Sharon K.; Banks, Bruce A.; Mirtich, Michael J.; Lebed, Richard; Brady, Joyce; Hotes, Deborah; Kussmaul, Michael
Geoeffective solar variability influence on Northern Hemisphere surface temperature
NASA Astrophysics Data System (ADS)
The complex interaction of the solar outputs such as electromagnetic radiation, solar wind and interplanetary magnetic field with terrestrial environment would affect the Earth's climate. Usually, the effect of solar variability on climate is taken into account only through changes in solar total and spectral irradiance. In this study, possible climatic effects related to geoeffective solar variability were investigated by means of long-term statistical correlations between surface air temperature and solar/geomagnetic indices. The data from NCEP/NCAR reanalysis database for the Northern Hemisphere have been processed. Spectral analysis indicates the occurrence of periodicities between 2 and 7 years, associated to atmospheric phenomena, and periodicities around 11 and 22 years, normally associated to solar variability. By applying simple filtering procedures we can get the 11 and 22-year signals in our temperature data. Various features of these signals will be discussed on different spatial scales of the Northern hemisphere. The differences between observed and reanalysed data will be also discussed.
Dobrica, Venera; Suteanu, Cristian; Stefan, Cristiana; Pirloaga, Razvan; Demetrescu, Crisan
Earth's Elastic Response to Seasonal Cycles in Surface Loading in Greenland and Antarctica
NASA Astrophysics Data System (ADS)
Newly installed polar geodetic networks such as the Greenland GPS Network (GNET) and the Antarctic GPS Network (ANET) provide a means to determine the movement of the Earth�s crust in response to past and present changes in ice mass. It is possible to distinguish between bedrock motions driven by glacial isostatic adjustment (GIA) - the response of the crust and mantle to past changes in ice mass, and those caused by the contemporary steady or time-linear component of the Earth�s instantaneous elastic response to present day changes in ice mass, by focusing on accelerations in secular rebound rates, which can only be due to accelerating trends in modern ice mass change. Seasonal cycles in crustal motion, which manifest Earth�s purely elastic response to cycles in surface loads, are completely distinguishable from GIA. However, we shall show that in many cases the seasonal displacement cycles recorded by GPS stations in Greenland and Antarctica manifest Earth�s elastic response to seasonal variations in atmospheric pressure as well as seasonal cycles in ice mass. Fortunately the atmospheric pressure cycles can be modeled quite well using data from existing meteorology stations, allowing the ice mass signal to be isolated - especially in the case of Greenland. In most situations when the pressure signal is removed, the seasonal elastic signal can be accounted for by seasonal variations in ice surface mass balance. Where this is not the case, it seems likely that variations in local ice dynamics that cause changes in local loads will be manifest. In addition to the investigation of the interplay between the cryosphere and the solid Earth the new polar geodetic networks are used for water vapor meteorology studies, analysis of ionospheric phenomena and space weather, and enhanced navigational support for airborne LIDAR surveys.
Kendrick, E. C.; Bevis, M. G.; Brown, A. K.; Madsen, F.; Khan, S. A.; Willis, M. J.; Vandam, T.; Forsberg, R.; Box, J. E.; Wilson, T. J.; Caccamise, D., II; Konfal, S. A.; Johns, B.
Mapping permeability over the surface of the Earth
Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional-scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed, at the regional scale, maps of permeability only exist for soil to depths of 1-2 m. Here we use an extensive compilation of results from hydrogeologic models to show that regional-scale (>5 km) permeability of consolidated and unconsolidated geologic units below soil horizons (hydrolithologies) can be characterized in a statistically meaningful way. The representative permeabilities of these hydrolithologies are used to map the distribution of near-surface (on the order of 100 m depth) permeability globally and over North America. The distribution of each hydrolithology is generally scale independent. The near-surface mean permeability is of the order of ???5 ?? 10-14 m2. The results provide the first global picture of near-surface permeability and will be of particular value for evaluating global water resources and modeling the influence of climate-surface-subsurface interactions on global climate change. Copyright ?? 2011 by the American Geophysical Union.
Gleeson, T.; Smith, L.; Moosdorf, N.; Hartmann, J.; Durr, H. H.; Manning, A. H.; Van Beek, L. P. H.; Jellinek, A. M.
Mapping permeability over the surface of the Earth
Permeability, the ease of fluid flow through porous rocks and soils, is a fundamental but often poorly quantified component in the analysis of regional-scale water fluxes. Permeability is difficult to quantify because it varies over more than 13 orders of magnitude and is heterogeneous and dependent on flow direction. Indeed, at the regional scale, maps of permeability only exist for soil to depths of 1-2 m. Here we use an extensive compilation of results from hydrogeologic models to show that regional-scale (>5 km) permeability of consolidated and unconsolidated geologic units below soil horizons (hydrolithologies) can be characterized in a statistically meaningful way. The representative permeabilities of these hydrolithologies are used to map the distribution of near-surface (on the order of 100 m depth) permeability globally and over North America. The distribution of each hydrolithology is generally scale independent. The near-surface mean permeability is of the order of -5 x 10-14 m2. The results provide the first global picture of near-surface permeability and will be of particular value for evaluating global water resources and modeling the influence of climate-surface-subsurface interactions on global climate change.
Gleeson, Tom; Smith, Leslie; Moosdorf, Nils; Hartmann, Jens; Durr, Hans H.; Manning, Andrew H.; van Beek, Ludovicus P. H.; Jellinek, A. M.
Asteroid surface mineralogy: Evidence from earth-based telescope observations
NASA Technical Reports Server (NTRS)
The interpretation of asteroid reflectance spectrophotometry in terms of mineralogical types gives inferred mineral assemblages for about 60 asteroids. Asteroid surface materials are compared with similar materials that make up many meteorites. The absence of asteroids with spectra that match identically the ordinary chondrites is noted.
Mccord, T. B.
Inversion of Static Displacement of the Earth's Surface.
National Technical Information Service (NTIS)
A method is presented which uses observations of surface displacement to place constraints on the components of the strain tensor at depth. Using a volume integral form of Volterra'a integral and a series expansion method, the problem is discretized. An e...
D. W. Vasco
The impact of land surface temperature on soil moisture anomaly detection from passive microwave observations
NASA Astrophysics Data System (ADS)
For several years passive microwave observations have been used to retrieve soil moisture from the Earth's surface. Low frequency observations have the most sensitivity to soil moisture, therefore the modern Soil Moisture and Ocean Salinity (SMOS) and future Soil Moisture Active and Passive (SMAP) satellite missions observe the Earth's surface in the L-band frequency. In the past, several satellite sensors such as the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and Windsat have been used to retrieve surface soil moisture using multi-channel observations obtained at higher microwave frequencies. While AMSR-E and Windsat lack an L-band channel, they are able to leverage multi-channel microwave observations to estimate additional land surface parameters. In particular, the availability of Ka-band observations allows AMSR-E and Windsat to obtain surface temperature estimates required for the retrieval of surface soil moisture. In contrast, SMOS and SMAP carry only a single frequency radiometer. Because of this, ancillary - and potentially less accurate - sources of surface temperature information (e.g. re-analysis data from operational weather prediction centers) must be sought to produce surface soil moisture retrievals. Here, two newly-developed, large-scale soil moisture evaluation techniques, the triple collocation (TC) approach and the R value data assimilation approach, are applied to quantify the global-scale impact of replacing Ka-band based surface temperature retrievals with Modern Era Retrospective-analysis for Research and Applications (MERRA) surface temperature predictions on the accuracy of Windsat and AMSR-E surface soil moisture retrievals. Results demonstrate that under sparsely vegetated conditions, the use of Ka-band radiometric land surface temperature leads to better soil moisture anomaly estimates compared to those retrieved using MERRA land surface temperature predictions. However the situation is reversed for highly vegetated conditions where soil moisture anomaly estimates retrieved using MERRA land surface temperature are superior. In addition, the surface temperature phase shifting approach is shown to generally enhance the value of MERRA surface temperature estimates for soil moisture retrieval. Finally, a high degree of consistency is noted between evaluation results produced by the TC and Rvalue soil moisture verification approaches.
Parinussa, R. M.; Holmes, T. R. H.; Crow, W. T.
Temperature dependent PAC studies with the rare earth 172Lu in ZnO
NASA Astrophysics Data System (ADS)
Wide band-gap semiconductors have become an important base material for applications in optoelectronics and in high power, high temperature electronics. After doping with various rare earths, electroluminescence throughout the whole visible spectrum has been observed. We have studied the implantation behaviour of the rare earth Lu in ZnO. Our samples were implanted at the ISOLDE facility at CERN. In order to recover the sustained implantation damage the samples were treated in a rapid thermal annealing furnace. In a first attempt to measure the temperature dependence of the electric field gradient at the site of 172Lu/ 172Yb in ZnO a large jump in the quadrupole interaction frequency was observed between measurements at room temperature and 200 �C. Above 200 �C the frequency only changed very little. In order to understand this unusual behaviour we prepared another sample and studied the temperature range between room temperature and 200 �C in more detail. The results obtained previously could be confirmed. The new data show a smooth increase of the quadrupole interaction frequency from about 146 MHz at room temperature to almost 390 MHz at 400 �C. This behaviour is likely to be due to the influence of the rare earth's partially filled 4f shell.
N�d�lec, R.; Vianden, R.; Isolde Collaboration
External forcing on air-surface temperature: Geographical distribution of sensitive climate zones
NASA Astrophysics Data System (ADS)
In this paper we analyze the geographical distribution of the climate response to external forcing (solar, volcanic and geomagnetic) on the periods of 11 and 22 years. As a climate characteristic we use the data of the air-surface temperature (regional data sets). The analysis is performed by the wavelet phase/coherence technique which is applied to the solar (sunspot numbers), volcanic (Dust Veil Index), geomagnetic (C9-index) activities and the temperature data on interannual timescales for the common time interval covering most of the 20th century. Besides, we analyze the statistics of the temperature response to the solar and geomagnetic factors on the periods of 11 and 22 years for different geographical sectors. In particular, we find the existence of a combined forcing of solar and volcanic activity on the Earth temperature on the 11-year period in the second half of the 20th century over the globe, whereas a set of stations (mostly in North Atlantic) shows a coherence between solar activity and the Earth temperature on the 11-year periodicity even in absence of the combined effect; it was found that the maximal number of stations demonstrating statistically significant amplitudes of wavelet spectra corresponds to the wavelet cross-coherence between geomagnetic activity and the Earth air-surface temperature on the periods about 22 years during the time interval without intensive volcanic eruptions capable to change significantly the level of DVIGlobal.
Barlyaeva, Tatiana V.
Temperature distribution along the surface of evaporating droplets
NASA Astrophysics Data System (ADS)
The surface temperature can significantly affect the flow field of drying droplets. Most previous studies assumed a monotonic temperature variation along the droplet surface. However, the present analyses indicate that a nonmonotonic spatial distribution of the surface temperature should occur. Three different patterns of the surface temperature distribution may appear during the evaporation process of liquid droplets: (i) the surface temperature increases monotonically from the center to the edge of the droplet; (ii) the surface temperature exhibits a nonmonotonic spatial distribution along the droplet surface; (iii) the surface temperature decreases monotonically from the center to the edge of the droplet. These surface temperature distributions can be explained by combining the evaporative cooling at the droplet surface and the heat conduction across the substrate and the liquid. Furthermore, a "phase diagram" for the distribution of the surface temperature is introduced and the effect of the spatial temperature distribution along the droplet surface on the flow structure of the droplet is discussed. The results may provide a better understanding of the Marangoni effect of drying droplets and provide a potential way to control evaporation-driven deposition as well as the assembly of colloids and other materials.
Zhang, Kai; Ma, Liran; Xu, Xuefeng; Luo, Jianbin; Guo, Dan
Temperature distribution along the surface of evaporating droplets.
The surface temperature can significantly affect the flow field of drying droplets. Most previous studies assumed a monotonic temperature variation along the droplet surface. However, the present analyses indicate that a nonmonotonic spatial distribution of the surface temperature should occur. Three different patterns of the surface temperature distribution may appear during the evaporation process of liquid droplets: (i) the surface temperature increases monotonically from the center to the edge of the droplet; (ii) the surface temperature exhibits a nonmonotonic spatial distribution along the droplet surface; (iii) the surface temperature decreases monotonically from the center to the edge of the droplet. These surface temperature distributions can be explained by combining the evaporative cooling at the droplet surface and the heat conduction across the substrate and the liquid. Furthermore, a "phase diagram" for the distribution of the surface temperature is introduced and the effect of the spatial temperature distribution along the droplet surface on the flow structure of the droplet is discussed. The results may provide a better understanding of the Marangoni effect of drying droplets and provide a potential way to control evaporation-driven deposition as well as the assembly of colloids and other materials. PMID:24730849
Zhang, Kai; Ma, Liran; Xu, Xuefeng; Luo, Jianbin; Guo, Dan
Exploring indicators for quantifying surface urban heat islands of European cities with MODIS land surface temperatures
The term urban heat island describes the phenomenon of altered temperatures in urban areas compared to their rural hinterlands. A surface urban heat island encompasses the patterns of land surface temperatures in urban areas. The classical indicator to describe a surface urban heat island is the difference between urban and rural surface temperatures. However, several other indicators for this purpose
Nina Schwarz; Sven Lautenbach; Ralf Seppelt
Disaggregation of GOES land surface temperatures using surface emissivity
NASA Astrophysics Data System (ADS)
Accurate temporal and spatial estimation of land surface temperatures (LST) is important for modeling the hydrological cycle at field to global scales because LSTs can improve estimates of soil moisture and evapotranspiration. Using remote sensing satellites, accurate LSTs could be routine, but unfortunately the only instruments available to provide diurnal cycle observations have coarse spatial resolution (4 km). One approach that may help overcome the spatial resolution constraint is to disaggregate geostationary LST data using visible to thermal infrared information provided by single time of day MODIS 1 km observations. These higher-resolution observations are correlative with observations at 4-km scales, and thus can be used to estimate 1-km LST values throughout a day. Inamdar et al 2008, for example, showed how GOES 10 imager and MODIS data could be combined to produce accurate half-hourly, 1-km LST values. However, the method disaggregated coarse LST values using Normalized Difference Vegetation Index (NDVI) data and was sometimes highly inaccurate when considering heterogeneous terrain. This problem can be greatly reduced with an alternative approach, whereby MODIS land cover emissivity data sets supply the needed 1-km information. In a study of LST estimation over the US Southwest, diurnal disaggregation models using emissivity data were significantly more accurate than a comparable NDVI-based model. This alternative approach which directly employs 8-day composites of MODIS 1 km emissivity is a simple and fast method.
Inamdar, Anand K.; French, Andrew
Evolution of land surface air temperature trend
NASA Astrophysics Data System (ADS)
The global climate has been experiencing significant warming at an unprecedented pace in the past century. This warming is spatially and temporally non-uniform, and one needs to understand its evolution to better evaluate its potential societal and economic impact. Here, the evolution of global land surface air temperature trend in the past century is diagnosed using the spatial-temporally multidimensional ensemble empirical mode decomposition method. We find that the noticeable warming (>0.5 K) started sporadically over the global land and accelerated until around 1980. Both the warming rate and spatial structure have changed little since. The fastest warming in recent decades (>0.4 K per decade) occurred in northern mid-latitudes. From a zonal average perspective, noticeable warming (>0.2 K since 1900) first took place in the subtropical and subpolar regions of the Northern Hemisphere, followed by subtropical warming in the Southern Hemisphere. The two bands of warming in the Northern Hemisphere expanded from 1950 to 1985 and merged to cover the entire Northern Hemisphere.
Ji, Fei; Wu, Zhaohua; Huang, Jianping; Chassignet, Eric P.
Surface Conduction in Rock at Low Temperature
NASA Astrophysics Data System (ADS)
Frozen rock exhibits anomalous conduction in that the conductivity is often greater than would be expected from simply substituting ice resistivity for pore water resistivity. Furthermore, the change in conductivity does not occur at 0oC but may be spread out over several degree or tens of degree. Several different mechanisms are probably responsible for this behaviour. One that has often been proposed is that the electric double layer is prevented from freezing by the strong electric fields that are present within it. Thus, ion mobility in the electric double layer remains high and surface conduction still contributes to conductivity even if the bulk pore water is frozen. In this work, the Gouy-Chapman theory is used to show that, at least for minerals with high cation exchange capacity, the electric field near the pore wall is large enough to polarize water and that a threshold potential, or equivalently threshold cation exchange capacity, exists below which polarization is not possible. Critical questions are; Can the threshold potential be confirmed by measurement? Is there evidence that polarization can inhibit freezing? Is there a critical temperature below which electrical polarization is not effective in preventing freezing? Experimental work with frozen electrodes confirms the existence of a threshold potential and suggests that the electric double layer can remain unfrozen for at least a few degrees below 0oC.
Merriam, J. B.
Surface-atmosphere interactions on Titan compared with those on the pre-biotic Earth.
The surface and atmosphere of Titan constitute a system which is potentially as complex as that of the Earth, with the possibility of precipitation, surface erosion due to liquids, chemistry in large surface or subsurface hydrocarbon reservoirs, surface expressions of internal activity, and occasional major impacts leading to crustal melting. While none of the above have been observed as yet, the composition, density and thermal properties of Titan's atmosphere make it uniquely suited in the outer solar system as a place where such processes may occur. The one attribute of the Earth not expected on Titan is biological activity, which has had a profound effect on the evolution of the Earth's surface-atmosphere system. The earliest environment of Titan could have been warm enough for liquid ammonia-water solutions to exist on or near surface; pre-biotic organic processes may have taken place in such an environment. After a few hundred million years surface ammonia-water would have disappeared. Therefore, study of Titan through the Cassini-Huygens mission, planned for launch in 1997, primarily affords the opportunity to understand planet-wide surface-atmosphere interactions in the presence of fluids but in the absence of life. More speculative is the possibility that endogenic and exogenic heating continue to provide short-lived environments on Titan wherein pre-biotic organic processes in the presence of water happen. PMID:11539243
Lunine, J I; McKay, C P
Surface-atmosphere interactions on Titan compared with those on the pre-biotic Earth
NASA Technical Reports Server (NTRS)
The surface and atmosphere of Titan constitute a system which is potentially as complex as that of the Earth, with the possibility of precipitation, surface erosion due to liquids, chemistry in large surface or subsurface hydrocarbon resevoirs, surface expressions of internal activity, and occasional major impacts leading to crustal melting. While none of the above have been observed as yet, the composition, density and thermal properties of Titan's atmosphere make it uniquely suited in the outer solar system as a place where such processes may occur. The one attribute of the Earth not expected on Titan is biological activity, which has had a profound effect on the evolution of the Earth's surface-atmosphere system. The earliest environment of Titan could have been warm enough for liquid ammonia-water solutions to exist on or near surface; pre-biotic organic processes may have taken place in such an environment. After a few hundred million years surface ammonia-water would have disappeard. Therefore, study of Titan through Cassini/Huygens mission, planned for launch in 1997, primarily affords the opportunity to understand planet-side surface-atmophsre interactions in the presence of fluids but in the absence of life. More speculative is the possibility that endogenic and exogenic heating continue to provide short-lived environments on Titan wherein pre-biotic organic processes in the presence of water happen.
Lunine, J. I.; Mckay, C. P.
No known rocks have survived from the first 500 m.y. of Earth history, but studies of single zircons suggest that some continental crust formed as early as 4.4 Ga, 160 m.y. after accretion of the Earth, and that surface temperatures were low enough for liquid water. Surface temperatures are inferred from high d18O values of zircons. The range of d18O
John W. Valley; William H. Peck; Elizabeth M. King; Simon A. Wilde
No known rocks have survived from the first 500 m.y. of Earth history, but studies of single zircons suggest that some continental crust formed as early as 4.4 Ga, 160 m.y. after accretion of the Earth, and that surface temperatures were low enough for liquid water. Surface temperatures are inferred from high delta18O values of zircons. The range of delta18O
John W. Valley; William H. Peck; Elizabeth M. King; Simon A. Wilde
An Attitude Control System to Constrain the Skin Temperature of a Manned Lifting Spacecraft During Reentry into the Earth'S Atmosphere.
National Technical Information Service (NTIS)
An attitude control system to regulate the temperature of a manned lifting spacecraft during reentry into the Earth's atmosphere is proposed. Its use prevents the peak skin temperature that is experienced during the reentry from rising moderately beyond t...
J. H. Fine
Surface waves on the tailward flanks of the Earth`s magnetopause
Forty-three examples of ISEE 1 tailward flank side magnetopause crossings are examined and directly compared with upstream solar wind parameters. The crossings are classified into two groups. In the first group, a few sudden magnetopause crossings are observed, whereas repeated magnetopause crossings and oscillatory motions, often with boundary layer signatures, are observed in the second group. These distinctive characteristics of the two groups are interpreted in terms of the surface waves due to the Kelvin-Helmholtz instability. It is found that low solar wind speed tends to favor characteristics of the first group, whereas high solar wind speed yields those of the second group. However, no evident correlations between the groups and the interplanetary magnetic field directions are found. 60 refs., 14 figs.
Seon, J.; Frank, L.A. [Univ. of Iowa, Iowa City, IA (United States)] [Univ. of Iowa, Iowa City, IA (United States); Lazarus, A.J. [Massachusetts Institute of Technology, Cambridge, MA (United States)] [and others] [Massachusetts Institute of Technology, Cambridge, MA (United States); and others
Surface Temperature Assimilation in the Global Land Data Assimilation System (GLDAS)
NASA Technical Reports Server (NTRS)
The Global Land Data Assimilation System (GLDAS) is a global land parameterization that uses prescribed meteorology as forcing in order to determine regular gridded land surface states (temperature and moisture) and other properties (e.g. water and heat fluxes). In the present experiment, the assimilation of surface skin temperature is incorporated into the land parameterizations. The meteorological forcing was derived from the Goddard Earth Observing System (GEOS-3) Data Assimilation System (DAS) for the full year of 1998 GLDAS can use several land parameterizations, but here we use the Mosaic land surface model and the Common Land Model (CLM). TOVS surface temperature observations are assimilated into GLDAS. The TOVS observations are less frequent that observations used in previous experiments (ISCCP). The purpose of this presentation is to evaluate the impact of the TOVS assimilation on both Mosaic and CLM. We will especially consider the impact of coarse temporal observations on the assimilation and bias correction.
Bosilovich, Michael G.; Radakovich, Jon D.; daSilva, Arlindo; Houser, Paul R.; Atlas, Robert M. (Technical Monitor)
Method for preparing high cure temperature rare earth iron compound magnetic material
Insertion of light elements such as H,C, or N in the R.sub.2 Fe.sub.17 (R=rare earth metal) series has been found to modify the magnetic properties of these compounds, which thus become prospective candidates for high performance permanent magnets. The most spectacular changes are increases of the Curie temperature, T.sub.c, of the magnetization, M.sub.s, and of coercivity, H.sub.c, upon interstitial insertion. A preliminary product having a component R--Fe--C,N phase is produced by a chemical route. Rare earth metal and iron amides are synthesized followed by pyrolysis and sintering in an inert or reduced atmosphere, as a result of which, the R--Fe--C,N phases are formed. Fabrication of sintered rare earth iron nitride and carbonitride bulk magnet is impossible via conventional process due to the limitation of nitridation method.
Huang, Yuhong (West Hills, CA); Wei, Qiang (West Hills, CA); Zheng, Haixing (Oak Park, CA)
Surface waves on the tailward flanks of the Earth's magnetopause
NASA Technical Reports Server (NTRS)
Forty-three examples of ISEE 1 tailward flank side magnetopause crossings are examined and directly compared with upstream solar wind parameters. The crossings are classified into two groups. In the first group, a few sudden magnetopause crossings are observed, whereas repeated magnetopause crossings and oscillatory motions, often with boundary layer signatures, are observed in the second group. These distinctive characteristics of the two groups are interpreted in terms of the surface waves due to the Kelvin-Helmholtz instability. It is found that low solar wind speed tends to favor characteristics of the first group, whereas high solar wind speed yields those of the second group. However, no evident correlations between the groups and the interplanetary magnetic field directions are found.
Seon, J.; Frank, L. A.; Lazarus, A. J.; Lepping, R. P.
High temperature rare earth compounds: Synthesis, characterization and applications in device fabrication
NASA Astrophysics Data System (ADS)
As the area of nanotechnology continues to grow, the development of new nanomaterials with interesting physical and electronic properties and improved characterization techniques are several areas of research that will be remain vital for continued improvement of devices and the understanding in nanoscale phenomenon. In this dissertation, the chemical vapor deposition synthesis of rare earth (RE) compounds is described in detail. In general, the procedure involves the vaporization of a REClx (RE = Y, La, Ce, Pr, Nd, Sm, Gd, Tb, Dy, Ho) in the presence of hydride phase precursors such as decaborane and ammonia at high temperatures and low pressures. Unlike traditional single source precursor techniques such as metal-organic chemical vapor deposition, the materials produced are of extremely high chemical purity. The crystallographic orientation of as-synthesized rare earth hexaboride nanostructures and gadolinium nitride thin films was controlled by judicious choice of specific growth substrates and modeled by analyzing x-ray diffraction powder patterns and crystallographic models. The vapor-liquid-solid mechanism was used in combination with the chemical vapor deposition process to synthesize single crystalline rare earth hexaboride nanostructures. Unlike previously reported synthetic techniques to generate rare earth hexaborides, my synthesis provided control over the tip diameter of the nanomaterials, was applicable to all available rare earth metals and utilized a chemical scheme that was much less toxic. Furthermore, the synthesis provided the first ever doped rare earth hexaboride nanowires. The as produced materials showed excellent electronic properties and could be applicable to many different types of electronic applications. The rare earth hexaboride nanostructures were then implemented into two existing technologies to enhance their characterization capabilities. First, the rare earth hexaboride nanowires were used as a test material for the development of a TEM based local electrode atom probe tomography (LEAP) technique. The TEM based LEAP technique is the first to combine atomic resolution crystallographic imaging with angstrom scale 3D compositional mapping. This technique also provided some of the first quantitative compositional information of the rare earth hexaboride systems and is applicable to a wide range of nanowire materials. Second, due to the rigidity and excellent conductivity of the rare earth hexaborides, nanostructures were grown onto tungsten wires for the development of robust, oxidation resistant nanomanipulator electronic probes for semiconductor device failure analysis.
Brewer, Joseph Reese
Modeling ultraviolet radiation at the Earth`s surface. Part II: Model and instrument comparison
High-resolution measurements in the spectral region of 280-400 nm using a double monochromator are compared with detailed radiative transfer calculations at Reading, United Kingdom (52{degrees}N, 0{degrees}), for clear and totally overcast days, using aerosol and cloud information deduced from empirical methods. For clear skies, instrument and model agree well in the UVA (320-400 nm), but agreement is worse in the UVB (280-320 nm). A number of possible reasons for the discrepancies are explored. Volcanic aerosols in the stratosphere of the model are found to improve agreement between the model and the instrument for high solar zenith angles by increasing the model UVB irradiances by as much as 6%. Convolving the model surface irradiances with the bandpass of the instrument leads to smaller differences between instrument and model at short wavelengths and also reduces the noisiness of the difference. When the model included stratospheric aerosol and the instrument`s bandpass function, UVB irradiances within 10% of the measured irradiances could be produced by the model for clear skies. For cloudy conditions, differences between instrument and model are larger, reaching 20%, integrated over the UVB. 17 refs., 20 figs., 1 tab.
Forster, P.M. de; Shine, K.P.; Webb, A.R. [Univ. of Reading, Whiteknights, Reading (United Kingdom)] [Univ. of Reading, Whiteknights, Reading (United Kingdom)
The melting temperature of iron hydride at high pressures and its implications for the temperature of the Earth's core
NASA Astrophysics Data System (ADS)
The Earth's core is about 10% less dense than pure iron under the relevant pressure and temperature conditions, so elements lighter than iron should exist in it. Recent experiments support the hypothesis that hydrogen dominates this light component. The hydrogen dissolved in metallic iron has a large potential to reduce its melting temperature. To estimate the melting temperature of the iron-hydrogen core, experiments were carried out at pressures up to 10 GPa by means of a new technique to determine the melting temperature and chemical composition from the textures of rapidly decompressed iron hydride grains. The rate of reduction of the melting temperature induced by adding hydrogen to iron was obtained as 0953-8984/10/49/052/img1 per unit mole fraction. If this behaviour of hydrogen persists to the much higher pressure deep inside the Earth, the isentrope in the iron-hydrogen core is about 600 K lower than the previous estimates based on experiments on the iron-sulphur-oxygen system.
Okuchi, Takuo
Modeling ultraviolet radiation at the Earth`s surface. Part I: The sensitivity of ultraviolet irradiances to atmospheric changes
A discrete-ordinate radiative transfer model is employed for the prediction of surface UV irradiances. A wide-ranging sensitivity study is undertaken to show how changes to the model input parameters affect UV irradiances at the surface. The effects of surface albedo, surface pressure, aerosol, cloud, and ozone on the UV irradiances are examined as well as the effects of model resolution. The ozone vertical profile and the temperature of the ozone layer are found to strongly influence UVB (280-320 nm) surface irradiances; the irradiance at 305 nm can be changed by as much as 17% for a fixed amount of total column ozone. The surface albedo is found to have a maximum influence on wavelengths near 320 nm; an uncertainty in the surface albedo of 0.2 leads to an 8% error in the UVB prediction. Clouds and tropospheric aerosol decrease the UV, their influence depending little on wavelength. Stratospheric aerosol is shown to be able to enhance the midwinter UVB surface irradiances while decreasing the UVA (320-400 nm) surface irradiances. 36 refs., 7 figs., 1 tab.
Forster, P.M. [Univ. of Reading, Whiteknights, Reading (United Kingdom)] [Univ. of Reading, Whiteknights, Reading (United Kingdom)
Relationship between Clouds and Sea Surface Temperatures in the Western Tropical Pacific.
NASA Astrophysics Data System (ADS)
Analysis of four years of earth radiation budget, cloud, and sea surface temperature data confirms that cloud parameters change dramatically when and where sea surface temperatures increase above 300 K. These results are based upon monthly mean values within 2.5��2.5� grid points over the `warm pool' region of the western tropical Pacific. The question of whether sea surface temperatures are influenced, in turn, by the radiative effects of thee clouds (Ramanathan and Collins) is less clear. Such a feedback, if it exists, is weak. The reason why clouds might have so little influence, despite large changes in their longwave and shortwave radiative effects, might be that the sea surface responds to both the longwave heating and the shortwave cooling effects of clouds, and the two effects nearly cancel. There are strong correlations between the rate of change of sea surface temperature and any of the radiation budget parameters that are highly correlated with the incident solar flux-implying that season and latitude are the critical factors determining sea surface temperatures. With the seasonal or both seasonal and latitudinal variations removed, the rate of change of sea surface temperature shows no correlation with cloud-related parameters in the western tropical Pacific.
Arking, Albert; Ziskin, Daniel
Relationship between clouds and sea surface temperatures in the western tropical Pacific
NASA Technical Reports Server (NTRS)
Analysis of four years of earth radiation budget, cloud, and sea surface temperature data confirms that cloud parameters change dramatically when and where sea surface temperatures increase above approximately 300K. These results are based upon monthly mean values within 2.5 deg x 2.5 deg grid points over the 'warm pool' region of the western tropical Pacific. The question of whether sea surface temperatures are influenced, in turn, by the radiative effects of these clouds (Ramanathan and Collins) is less clear. Such a feedback, if it exists, is weak. The reason why clouds might have so little influence, despite large changes in their longwave and shortwave radiative effects, might be that the sea surface responds to both the longwave heating and the shortwave cooling effects of clouds, and the two effects nearly cancel. There are strong correlations between the rate of change of sea surface temperature and any of the radiation budget parameters that are highly correlated with the incident solar flux-implying that season and latitude are the critical factors determining sea surface temperatures. With the seasonal or both seasonal and latitudinal variations removed, the rate of change of sea surface temperature shows no correlation with cloud-related parameters in the western tropical Pacific.
Arking, Albert; Ziskin, Daniel
Electrokinetic effect in the near-surface layers of the Earth
The electric field in the near-surface layers of a spherically symmetrical Earth was calculated. This electric field is generated by electrokinetic processes in a water-saturated porous medium deformed by lunisolar tides. An exact analytical solution of the Frenkel' equations describing electrokinetic phenomena is found. Data of observations of the horizontal components of the electric field are processed. The main harmonics
M. B. Gokhberg; N. I. Kolosnitsyn; V. M. Lapshin
Circular structures of large scale and great age on the earth's surface
It is pointed out that the earth's surface exhibits faint circular patterns which have not been described before. These circles are characterized by near perfection of outline, by the presence of topographic highs (rims) along parts of their circumferences, and by their generally large scale (diameters from 7 to 700 km). Circles of this nature have been observed clearly in
J. M. Saul
The effect of the hydrology of the earth's surface is incorporated into a numerical model of the general circula- tion of the atmosphere developed at the Geophysical Fluid Dynamics Laboratory of the Environmental Science Services Administration (ESSA). The primitive equation of motion is used for this study. The nine levels of the model are distributed so as to resolve the
Radar interferometry and its application to changes in the earth's surface
Geophysical applications of radar inter- ferometry to measure changes in the Earth's surface have exploded in the early 1990s. This new geodetic technique calculates the interference pattern caused by the difference in phase between two images acquired by a spaceborne synthetic aperture radar at two distinct times. The resulting interferogram is a contour map of the change in distance between
Didier Massonnet; Kurt L. Feigl
Implications of recent total atmospheric ozone measurements for biologically active ultraviolet radiation reaching the earth's surface
Recent satellite measurements of total atmospheric ozone were analyzed to deduce the changes in biologically active ultraviolet (UV) radiation reaching the Earth's surface from 1979 to 1989. The calculated increases are on average substantially larger than earlier estimates, particularly at mid and high latitudes of both hemispheres. Over the last twenty years, there has been some concern that biologically active
Sasha Madronich
Surface reactions on rare earth metals monitored by work function measurements
Surface reactions on clean, oxidized, and partially hydrided rare earth metal films with O�, H�, H�O, CO, and CO� were monitored by dynamic work function measurements under ultrahigh vacuum conditions. The work function data are discussed in the light of electron spectroscopic evidence, where available. The main results of this study are: Initial oxidation of Yb seems to follow a
G. Strasser; E. Bertel; F. P. Netzer
Radiogenic isotopes: systematics and applications to earth surface processes and chemical stratigraphy
Radiogenic isotopes have wide application to chemical stratigraphy, geochronology, provenance studies, and studies of temporal changes in Earth surface processes. This paper briefly reviews the principles of radiogenic isotope geochemistry and the distribution of a number of elements of interest in the environment, and then uses this information to explore the range of applications to chemical stratigraphy and other fundamental
Jay L. Banner
Investigation of short period variations of ozone concentration near the earth's surface: instrumental base and results
Variations of ozone concentration (O3) and intensity of solar radiation (ISR) near the earth surface with periods 3.1 (mu) at 6.2 min were observed. The ozone measurements were carried out with the help of special chemiluminescent ozonometer.
Vitaly Sirota
Validation of near-real-time sea surface temperature from MODIS in the ocean around Japan
We have examined accuracies of Moderate Resolution Imaging Spectroradiometer (MODIS) aboard Terra and Aqua using near-real-time sea surface temperature (SST) algorithm produced by Japan Aerospace Exploration Agency, Earth Observation Research and application Center (JAXA\\/EORC). The algorithm was tuned by buoy bulk SST observation around Japan in the period from February to April, 2004. The Multi-Channel SST (MCSST) coefficients were derived
Kohtaro Hosoda; Hiroshi Murakami
Validating MODIS land surface temperature products using long-term nighttime ground measurements
The Moderate Resolution Imaging Spectroradiometer (MODIS), onboard the NASA Terra and Aqua Earth Observing System satellites, provides multiple land surface temperature (LST) products on a daily basis. However, these products have not been adequately validated. This paper presents preliminary results of validating two MODIS Terra daily LST products, MOD11_L2 (version 4) and MOD07_L2 (version 4), using the FLUXNET and Carbon
Wenhui Wang; Shunlin Liang; Tilden Meyers
Global Sea Surface Temperature Analyses: Multiple Problems and Their Implications for Climate Analysis, Modeling, and Reanalysis
A comprehensive comparison is made among four sea surface temperature (SST) datasets: the optimum interpo- lation (OI) and the empirical orthogonal function reconstructed SST analyses from the National Centers for Environ- mental Prediction (NCEP), the Global Sea-Ice and SST dataset (GISST, version 2.3b) from the United Kingdom Meteorological Office, and the optimal smoothing SST analysis from the Lamont-Doherty Earth Observatory
James W. Hurrell; Kevin E. Trenberth
The warming trend of ground surface temperature in the Choshui Alluvial Fan, western central Taiwan
NASA Astrophysics Data System (ADS)
Heat storage in subsurface of the continents forms a fundamental component of the global energy budget and plays an important role in the climate system. Several researches revealed that subsurface temperatures were being increased to 1.8-2.8�C higher in mean ground surface temperature (GST) for some Asian cities where are experiencing a rapid growth of population. Taiwan is a subtropic-tropic island with densely populated in the coastal plains surrounding its mountains. We investigate the subsurface temperature distribution and the borehole temperature-depth profiles by using groundwater monitoring wells in years 2000 and 2010. Our data show that the western central Taiwan plain also has been experiencing a warming trend but with a higher temperatures approximately 3-4 �C of GST during the last 250 yrs. We suggest that the warming were mostly due to the land change to urbanization and agriculture. The current GSTs from our wells are approximately 25.51-26.79 �C which are higher than the current surface air temperature (SAT) of 23.65 �C. Data from Taiwan's weather stations also show 1-1.5 �C higher for the GST than the SAT at neighboring stations. The earth surface heat balance data indicate that GST higher than SAT is reasonable. More researches are needed to evaluate the interaction of GST and SAT, and how a warming GST's impact to the SAT and the climate system of the Earth.
Chen, W.; Chang, M.; Chen, J.; Lu, W.; Huang, C. C.; Wang, Y.
Indications for a surface temperature excess in heterogeneous catalysis.
We explored the surface temperature excess DeltaT = T(r) - T(m) (real reaction temperature T(r), measured catalyst temperature T(m)) on the basis of experimental data, a gradually curved Arrhenius plot for CO oxidation reactions over Pd/gamma-Al(2)O(3) catalysts. Such a plot could be an indication of the surface temperature excess in the 2-dimensional reaction surfaces of catalysts. The positive or negative surface temperature excess could be developed to be a general explanation for a gradually curved Arrhenius plot of a gas-solid catalytic system. This is a new insight into solving the puzzle on such common phenomena in heterogeneous catalysis. By using the reciprocal of the real reaction temperature T(r) in the hypothetical 2-D reaction surface, instead of the experimentally determined catalyst temperature T(m) or the gas temperature T(g), the gradually curved Arrhenius plot becomes linear. We investigated the implications of such a difference among T(r), T(m), and T(g). The surface temperature excess could be the effect of coupling between the fluxes of a chemical reaction and heat transport in the 2-D reaction surface. Its order of magnitude is 10 K for the present model system.(1) The surface temperature excess increases exponentially with the reaction temperature. PMID:16970451
Zhu, Lianjie; Frens, Gert
Detectability of Surface and Atmospheric Signatures in the Disk-averaged Spectra of the Earth
We have developed a spatially and spectrally-resolved computer model of the Earth to explore the observational sensitivity to atmospheric and surface properties, and biosignatures, in disk-averaged spectra.This comprehensive model can also be used to analyze and interpret Earthshine data.Atmospheric, cloud and surface properties from existing observations and modeling studies are input to the model, which uses the Spectral Mapping Atmospheric
G. Tinetti; V. S. Meadows; D. Crisp; N. Kiang; E. Fishbein; B. Kahn; M. Turnbull
Earth surface reflectivity climatology at 340�380 nm from TOMS data
The 340-380 nm (UV) Lambertian equivalent reflectivities (LER) of the Earth's surface, between the latitudes +70 � , are constructed from 14.5 years of radiances measured by Nimbus-7\\/total ozone mapping spectrometer (November 1978 to May 1993). The surface LER values are obtained from the minimum reflectivity values for each 1 � x 1.25 � (latitude x longitude) pixel with statistically
J. R. Herman; E. A. Celarier
Mass Redistribution in the Core and Time-varying Gravity at the Earth's Surface
NASA Technical Reports Server (NTRS)
The Earth's liquid outer core is in convection, as suggested by the existence of the geomagnetic field in much of the Earth's history. One consequence of the convection is the redistribution of mass resulting from relative motion among fluid parcels with slightly different densities. This time dependent mass redistribution inside the core produces a small perturbation on the gravity field of the Earth. With our numerical dynamo solutions, we find that the mass redistribution (and the resultant gravity field) symmetric about the equator is much stronger than that anti-symmetric about the equator. In particular, J(sub 2) component is the strongest. In addition, the gravity field variation increases with the Rayleigh number that measures the driving force for the geodynamo in the core. With reasonable scaling from the current dynamo solutions, we could expect that at the surface of the Earth, the J(sub 2) variation from the core is on the order of l0(exp -16)/year relative to the mean (i.e. spherically symmetric) gravity field of the Earth. The possible shielding effect due to core-mantle boundary pressure variation loading is likely much smaller and is therefore negligible. Our results suggest that time-varying gravity field perturbation due to core mass redistribution may be measured with modem space geodetic observations, which will result a new means of detecting dynamical processes in the Earth's deep interior.
Kuang, Wei-Jia; Chao, Benjamin F.; Fang, Ming
Downscaling MODIS Land Surface Temperature for Urban Public Health Applications
NASA Technical Reports Server (NTRS)
This study is part of a project funded by the NASA Applied Sciences Public Health Program, which focuses on Earth science applications of remote sensing data for enhancing public health decision-making. Heat related death is currently the number one weather-related killer in the United States. Mortality from these events is expected to increase as a function of climate change. This activity sought to augment current Heat Watch/Warning Systems (HWWS) with NASA remotely sensed data, and models used in conjunction with socioeconomic and heatrelated mortality data. The current HWWS do not take into account intra-urban spatial variation in risk assessment. The purpose of this effort is to evaluate a potential method to improve spatial delineation of risk from extreme heat events in urban environments by integrating sociodemographic risk factors with estimates of land surface temperature (LST) derived from thermal remote sensing data. In order to further improve the consideration of intra-urban variations in risk from extreme heat, we also developed and evaluated a number of spatial statistical techniques for downscaling the 1-km daily MODerate-resolution Imaging Spectroradiometer (MODIS) LST data to 60 m using Landsat-derived LST data, which have finer spatial but coarser temporal resolution than MODIS. In this paper, we will present these techniques, which have been demonstrated and validated for Phoenix, AZ using data from the summers of 2000-2006.
Al-Hamdan, Mohammad; Crosson, William; Estes, Maurice Jr.; Estes, Sue; Quattrochi, Dale; Johnson, Daniel
Downscaling MODIS Land Surface Temperature for Urban Public Health Applications
NASA Astrophysics Data System (ADS)
This study is part of a project funded by the NASA Applied Sciences Public Health Program, which focuses on Earth science applications of remote sensing data for enhancing public health decision-making. Heat related death is currently the number one weather-related killer in the United States. Mortality from these events is expected to increase as a function of climate change. This activity sought to augment current Heat Watch/Warning Systems (HWWS) with NASA remotely sensed data, and models used in conjunction with socioeconomic and heat-related mortality data. The current HWWS do not take into account intra-urban spatial variations in risk assessment. The purpose of this effort is to evaluate a potential method to improve spatial delineation of risk from extreme heat events in urban environments by integrating sociodemographic risk factors with land surface temperature (LST) estimates derived from thermal remote sensing data. In order to further improve the assessment of intra-urban variations in risk from extreme heat, we developed and evaluated a number of spatial statistical techniques for downscaling the 1-km daily MODerate-resolution Imaging Spectroradiometer (MODIS) LST data to 60 m using Landsat-derived LST data, which have finer spatial but coarser temporal resolution than MODIS. We will present these techniques, which have been demonstrated and validated for Phoenix, AZ using data from the summers of 2000-2006.
Al-Hamdan, M. Z.; Crosson, W. L.; Estes, M. G., Jr.; Estes, S. M.; Quattrochi, D. A.; Johnson, D.
A plume model of transient diachronous uplift at the Earth's surface
NASA Astrophysics Data System (ADS)
Convection in the Earth's mantle appears to be strongly time-dependent on geological time scales. However, we lack direct observations which would help constrain the temporal variation of convection on time scales of 1-10 Ma. Recently, it has been demonstrated that transient uplift events punctuated the otherwise uniform thermal subsidence of sedimentary basins which fringe the Icelandic plume. In the Faroe-Shetland basin, three-dimensional seismic reflection surveys calibrated by well logs have been used to reconstruct a � 55 million year old transient event. The minimum amount of uplift is 490 m, which grew and decayed within 2 Ma. This event has also been mapped 400 km further east in the North Sea basin, where peak uplift with an amplitude of 300 m occurred 0.3-1.6 Ma later. Neither observation can be explained by glacio-eustatic sea-level changes or by crustal shortening. We describe a simple fluid dynamical model which accounts for these transient and diachronous observations. In this model, we assume that the Icelandic plume was already in existence and that it had an axisymmetric geometry in which hot (e.g. 1400 �C) asthenospheric material flows away from a central conduit within a horizontal layer. A transient temperature anomaly introduced at the plume centre flows outward as an expanding annulus. Its geometry is calculated using radial flow between two parallel plates with a Poiseuille cross-stream velocity profile. The expanding annulus of hot asthenosphere generates transient isostatic uplift at the Earth's surface. Stratigraphic observations from both basins can be accounted for using a plume flux of 1.3 � 10 8 km 3 Ma - 1 for a layer thickness of 100 km. Plume flux is broadly consistent with that required to account for Neogene (0-20 Ma) V-shaped ridges south of Iceland, although our transient temperature anomalies are larger. We suspect that the stratigraphic expression of transient convective behaviour is common and that a careful examination of appropriate records could yield important insights.
Rudge, John F.; Shaw Champion, Max E.; White, Nicky; McKenzie, Dan; Lovell, Bryan
Examine infrared images that show variation in surface temperature
NSDL National Science Digital Library
Find a somewhat blurry Flash animation exhibiting five years worth of surface average temperatures. Note seasonal land/water temperature contrasts. The animation can be paused and rewound to emphasize important points.
Observatory, Nasa E.; Earth, Exploring
Surface Fatigue Life of High Temperature Gear Materials.
National Technical Information Service (NTIS)
Three high temperature gear materials were evaluated using spur gear surface fatigue tests. These materials were, VASCO max 350, VASCO matrix 2, and nitralloy N and were evaluated for possible use in high temperature gear applications. The fatigue life of...
D. P. Townsend
NSDL National Science Digital Library
This page contains details about the planet Earth. Information includes planet diameter, mass, distance from the Sun, orbit, and mythology. Also covered is planet composition, surface features, atmosphere and magnetic field data, temperature on planet, and data on its satellite: the Moon. Links are provided to more images, movies, and information about the Earth and Moon. This site discusses unanswered questions about Earth as well.
Arnett, Bill
Enhancement of palladium-porphyrin room temperature phosphorescence by alkaline earth metal in deoxycholate aggregates solution.
Room temperature phosphorescence (RTP) of three palladium (Pd)-phorphyrins in air-saturated solution of sodium deoxycholate (NaDC) aggregates was measured. RTP of Pd-meso-tetrakis (4-carboxyphenyl) porphyrin (Pd-TCPP) was obviously enhanced in NaDC-aggregates mediated by alkaline earth metal (AEM). Under the same experimental conditions, Ca(2+), Ba(2+) and Mg(2+) induced 200, 90 and 24 times greater enhancement in RTP of Pd-TCPP, respectively. It is ascribed to form the complex of NaDC-aggregate/AEM/Pd-TCPP in the system. The positively charged AEM has a strong capability of co-ordination with negatively charged carboxyl groups of NaDC and Pd-TCPP. The phosphor Pd-TCPP is confined in rigid NaDC-aggregates/AEM system by the coordination which decreases the probability of collision of phosphor with quenchers such as dissolved oxygen molecules and prolongs the lifetime of the phosphor on the triplet state. Long excited-state lifetimes resulted in great enhancement of Pd-TCPP phosphorescence. Observations by optical microscope showed that specific fan-like structures of NaDC were formed under the influence of AEM. Surface tension measurements supported a close interaction between Ca(2+) ions and anion aggregates of NaDC with 1:1 stoichiometric ratio. Due to its outstanding RTP behavior in NaDC-aggregates induced by Ca(2+), Pd-TCPP was used as a RTP probe to detect bovine serum albumin (BSA). A broad linear range from 1.0 � 10(-9) to 9.0 � 10(-7) g mL(-1) was obtained. Detection limit is 2.6 � 10(-11) g mL(-1), the relative standard deviation (n = 6) is 2.3% for 2.0 � 10(-9) g mL(-1) BSA. PMID:21438880
Wang, Ying-Te; Wang, Xiang-Wei; Zhang, Yong
Temperature dependent droplet impact dynamics on flat and textured surfaces
Droplet impact dynamics determines the performance of surfaces used in many applications such as anti-icing, condensation, boiling and heat transfer. We study impact dynamics of water droplets on surfaces with chemistry/texture ranging from hydrophilic to superhydrophobic and across a temperature range spanning below freezing to near boiling conditions. Droplet retraction shows very strong temperature dependence especially for hydrophilic surfaces; it is seen that lower substrate temperatures lead to lesser retraction. Physics-based analyses show that the increased viscosity associated with lower temperatures can explain the decreased retraction. The present findings serve to guide further studies of dynamic fluid-structure interaction at various temperatures.
Azar Alizadeh; Vaibhav Bahadur; Sheng Zhong; Wen Shang; Ri Li; James Ruud; Masako Yamada; Liehi Ge; Ali Dhinojwala; Manohar S Sohal (047160)
Evaluation of the Present Theoretical Basis for Determination of Planetary Surface Properties by Earth-Based Radar.
National Technical Information Service (NTIS)
Spaceflight programs such as the planned Viking landing on Mars require the determination of planetary surface slopes and surface dielectric constants by earth-based methods. Heavy reliance is often placed on radar backscattering data for estimation of th...
L. D. Staton
Application of the Zisman critical surface tension technique to ceramic surfaces at high temperature
The critical surface tension technique is one of many possible approaches that can be used to determine the energy of ceramic surfaces at high temperature. Although it has been shown to agree with other techniques used at low temperature, previous attempts at high temperatures have failed. This study is the first to use this technique successfully at high temperatures. It
D. A. Weirauch; P. Darrell Ownby
Fourier power spectra of the geomagnetic field for circular paths on the Earth's surface.
The Fourier power spectra of geomagnetic component values, synthesized from spherical harmonic models, have been computed for circular paths on the Earth's surface. They are not found to be more useful than is the spectrum of magnetic energy outside the Earth for the purpose of separating core and crustal sources of the geomagnetic field. The Fourier power spectra of N and E geomagnetic components along nearly polar great circle paths exhibit some unusual characteristics that are explained by the geometric perspective of Fourier series on spheres developed by Yee. -Authors
Alldredge, L. R.; Benton, E. R.
Mapping the Earth's thermochemical and anisotropic structure using global surface wave data
NASA Astrophysics Data System (ADS)
We have inverted global fundamental mode and higher-order Love and Rayleigh wave dispersion data jointly, to find global maps of temperature, composition, and radial seismic anisotropy of the Earth's mantle as well as their uncertainties via a stochastic sampling-based approach. We apply a self-consistent thermodynamic method to systematically compute phase equilibria and physical properties (P and S wave velocity, density) that depend only on composition (in the Na2-CaO-FeO-MgO-Al2O3-SiO2 model system), pressure, and temperature. Our 3-D maps are defined horizontally by 27 different tectonic regions and vertically by a number of layers. We find thermochemical differences between oceans and continents to extend down to �250 km depth, with continents and cratons appearing chemically depleted (high magnesium number (Mg #) and Mg/Si ratio) and colder (>100�C) relative to oceans, while young oceanic lithosphere is hotter than its intermediate age and old counterparts. We find what appears to be strong radial S wave anisotropy in the upper mantle down to �200 km, while there seems to be little evidence for shear anisotropy at greater depths. At and beneath the transition zone, 3-D heterogeneity is likely uncorrelated with surface tectonics; as a result, our tectonics-based parameterization is tenuous. Despite this weakness, constraints on the gross average thermochemical and anisotropic structure to �1300 km depth can be inferred, which appear to indicate that the compositions of the upper (low Mg# and high Mg/Si ratio) and lower mantle (high Mg# and low Mg/Si ratio) might possibly be distinct.
Khan, A.; Boschi, L.; Connolly, J. A. D.
Temperature sensitive surfaces and methods of making same
Poly-n-isopropylacrylamide surface coatings demonstrate the useful property of being able to switch charateristics depending upon temperature. More specifically, these coatings switch from being hydrophilic at low temperature to hydrophobic at high temperature. Research has been conducted for many years to better characterize and control the properties of temperature sensitive coatings. The present invention provides novel temperature sensitive coatings on articles and novel methods of making temperature sensitive coatings that are disposed on the surfaces of various articles. These novel coatings contain the reaction products of n-isopropylacrylamide and are characterized by their properties such as advancing contact angles. Numerous other characteristics such as coating thickness, surface roughness, and hydrophilic-to-hydrophobic transition temperatures are also described. The present invention includes articles having temperature-sensitve coatings with improved properties as well as improved methods for forming temperature sensitive coatings.
Liang, Liang [Richland, WA; Rieke, Peter C [Pasco, WA; Alford, Kentin L [Pasco, WA
Surface temperature distribution and infrared radiation feature of a spatial balloon decoy
NASA Astrophysics Data System (ADS)
The space heat flux that the spatial balloon decoy gets is calculated in the appropriate coordinate system and the earth heat flux is calculated accurately with the use of the unit hemisphere method. The surface temperature distribution of the balloon decoy is got by solving the transient heat balance equations with the use of the finite element software, ANSYS 10.0. On the basis of the solved surface temperature distribution, taking the balloon decoy as a point object, the spatial distribution of infrared radiation intensity in 3~6um and in 6~16um is calculated. Finally, the differences of the surface temperature distribution and the infrared radiation intensity spatial distribution between the spatial balloon decoy got in this paper and a spatial target got in our previous work are compared and analyzed in detail. The research results of this paper have referential value on infrared automatic target recognition (ATR) of spatial targets.
Wu, Xiao-Di; Lv, Xiang-Yin; Yang, Hua; Huang, Chao-Chao
Temperature dependence of rare-earth orthoferrite properties relevant to propagating domain device applications
The behavior of stable cylindrical domains, under variations in temperature, has been studied in a number of the rare-earth orthoferrites from the point of view of the need for temperature control when these materials are used in propagating domain devices. Fractional changes in domain diameter from -0.60 percent\\/�K in YFeO3to -2.71 percent\\/�K in a mixed orthoferrite, Sm0.55Tb0.45FeO3have been observed at
F. Rossol
Earth materials and earth dynamics
In the project ''Earth Materials and Earth Dynamics'' we linked fundamental and exploratory, experimental, theoretical, and computational research programs to shed light on the current and past states of the dynamic Earth. Our objective was to combine different geological, geochemical, geophysical, and materials science analyses with numerical techniques to illuminate active processes in the Earth. These processes include fluid-rock interactions that form and modify the lithosphere, non-linear wave attenuations in rocks that drive plate tectonics and perturb the earth's surface, dynamic recrystallization of olivine that deforms the upper mantle, development of texture in high-pressure olivine polymorphs that create anisotropic velocity regions in the convecting upper mantle and transition zone, and the intense chemical reactions between the mantle and core. We measured physical properties such as texture and nonlinear elasticity, equation of states at simultaneous pressures and temperatures, magnetic spins and bonding, chemical permeability, and thermal-chemical feedback to better characterize earth materials. We artificially generated seismic waves, numerically modeled fluid flow and transport in rock systems and modified polycrystal plasticity theory to interpret measured physical properties and integrate them into our understanding of the Earth. This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL).
Bennett, K; Shankland, T. [and others
Reproducibility of UAV-based earth surface topography based on structure-from-motion algorithms.
NASA Astrophysics Data System (ADS)
A representation of the earth surface at very high spatial resolution is crucial to accurately map small geomorphic landforms with high precision. Very high resolution digital surface models (DSM) can then be used to quantify changes in earth surface topography over time, based on differencing of DSMs taken at various moments in time. However, it is compulsory to have both high accuracy for each topographic representation and consistency between measurements over time, as DSM differencing automatically leads to error propagation. This study investigates the reproducibility of reconstructions of earth surface topography based on structure-from-motion (SFM) algorithms. To this end, we equipped an eight-propeller drone with a standard reflex camera. This equipment can easily be deployed in the field, as it is a lightweight, low-cost system in comparison with classic aerial photo surveys and terrestrial or airborne LiDAR scanning. Four sets of aerial photographs were created for one test field. The sets of airphotos differ in focal length, and viewing angles, i.e. nadir view and ground-level view. In addition, the importance of the accuracy of ground control points for the construction of a georeferenced point cloud was assessed using two different GPS devices with horizontal accuracy at resp. the sub-meter and sub-decimeter level. Airphoto datasets were processed with SFM algorithm and the resulting point clouds were georeferenced. Then, the surface representations were compared with each other to assess the reproducibility of the earth surface topography. Finally, consistency between independent datasets is discussed.
Clapuyt, Fran�ois; Vanacker, Veerle; Van Oost, Kristof
GHG Effect on Surface Temperature in Indonesia
NASA Astrophysics Data System (ADS)
The increasing of green house gas emissons into the atmosphere could influence the Climate and Earth Ecosystem. The increasing CO_2 emmision in developed countries and developing countries are influenced by economic growth factor, cheaped price fuel without tax and there is not regulation yet for making arrangement energy efficiency. The result of inventarisation CO_2 emmision related to energy sector between 1990 until 2000 in Indonesia are having increased trend, and the CO_2 emmision percapita is still lower then OECD countries. The green house gas concentrations are measured continously in Bandung, Jakarta, and the others place. The CO_2 and CH_4 concentration ever had results higher than globally mean. The fluctuation of green house gas concentrations are influenced by activities of surounding research location.
Cahyono, W. E.
MY NASA DATA: Sea Surface Temperature Trends of the Gulf Stream
NSDL National Science Digital Library
In this lesson, students investigate and analyze the connection between sea surface temperatures and the flow pattern of the Gulf Stream current. Students will generate an Excel file of sea surface temperatures for the Gulf Stream region from data stored on the Live Access Server. In addition, students will also access and plot seasonal water temperature changes from different time periods. This will allow for a comparison of maximum and minimum temperature fluctuations as well as seasonal variations for locations throughout the Gulf Stream. Students will also explore the Gulf Stream�s affects on weather and offshore industries. This lesson uses student- and citizen science-friendly microsets of authentic NASA Earth system science data from the MY NASA DATA project. It also includes related links, extension, an online glossary, and a list of related AP Environmental Science topics.
Estimation of Surface Heat Flux and Surface Temperature during Inverse Heat Conduction under Varying Spray Parameters and Sample Initial Temperature
An experimental study was carried out to investigate the effects of inlet pressure, sample thickness, initial sample temperature, and temperature sensor location on the surface heat flux, surface temperature, and surface ultrafast cooling rate using stainless steel samples of diameter 27?mm and thickness (mm) 8.5, 13, 17.5, and 22, respectively. Inlet pressure was varied from 0.2?MPa to 1.8?MPa, while sample initial temperature varied from 600�C to 900�C. Beck's sequential function specification method was utilized to estimate surface heat flux and surface temperature. Inlet pressure has a positive effect on surface heat flux (SHF) within a critical value of pressure. Thickness of the sample affects the maximum achieved SHF negatively. Surface heat flux as high as 0.4024?MW/m2 was estimated for a thickness of 8.5?mm. Insulation effects of vapor film become apparent in the sample initial temperature range of 900�C causing reduction in surface heat flux and cooling rate of the sample. A sensor location near to quenched surface is found to be a better choice to visualize the effects of spray parameters on surface heat flux and surface temperature. Cooling rate showed a profound increase for an inlet pressure of 0.8?MPa.
Aamir, Muhammad; Liao, Qiang; Zhu, Xun; Aqeel-ur-Rehman; Wang, Hong
A simplified physically-based model to calculate surface water temperature of lakes from air temperature in climate change scenarios
NASA Astrophysics Data System (ADS)
Modifications of water temperature are crucial for the ecology of lakes, but long-term analyses are not usually able to provide reliable estimations. This is particularly true for climate change studies based on Global Circulation Models, whose mesh size is normally too coarse for explicitly including even some of the biggest lakes on Earth. On the other hand, modeled predictions of air temperature changes are more reliable, and long-term, high-resolution air temperature observational datasets are more available than water temperature measurements. For these reasons, air temperature series are often used to obtain some information about the surface temperature of water bodies. In order to do that, it is common to exploit regression models, but they are questionable especially when it is necessary to extrapolate current trends beyond maximum (or minimum) measured temperatures. Moreover, water temperature is influenced by a variety of processes of heat exchange across the lake surface and by the thermal inertia of the water mass, which also causes an annual hysteresis cycle between air and water temperatures that is hard to consider in regressions. In this work we propose a simplified, physically-based model for the estimation of the epilimnetic temperature in lakes. Starting from the zero-dimensional heat budget, we derive a simplified first-order differential equation for water temperature, primarily forced by a seasonally varying external term (mainly related to solar radiation) and an exchange term explicitly depending on the difference between air and water temperatures. Assuming annual sinusoidal cycles of the main heat flux components at the atmosphere-lake interface, eight parameters (some of them can be disregarded, though) are identified, which can be calibrated if two temporal series of air and water temperature are available. We note that such a calibration is supported by the physical interpretation of the parameters, which provide good initial conditions. As a general result, the model allows one to obtain long-term series of estimated water temperatures, which can be valuably considered in climate change studies. The model has been applied to different lakes (Lake Baikal, Siberia; Lake Garda, Italy; Great Lakes, Canada and USA; Lake Mara, Canada) showing a noticeable agreement with the validation datasets and allowing for predictions of future trends of lake surface water temperature. Finally, it is worth noting that if the model is calibrated using air temperature series from climate models (global scale) and measured records of water temperature (lake scale), air temperatures are contemporaneously converted and downscaled. In conclusion, the model can be used as a downscaling tool, both for historical conditions and projected scenarios.
Piccolroaz, S.; Toffolon, M.
On surface temperature, greenhouse gases, and aerosols: models and observations
The effect of changes in atmospheric carbon dioxide concentrations and sulphate aerosols on near-surface temperature is investigated using a version of the Hadley Centre atmospheric model coupled to a mixed layer ocean. The scattering of sunlight by sulphate aerosols is represented by appropriately enhancing the surface albedo. On doubling atmospheric carbon dioxide concentrations, the global mean temperature increases by 5.2
J. F. B. Mitchell; R. A. Davis; W. J. Ingram; C. A. Senior
Remote sensing: Earth's surface and atmosphere; Proceedings of Workshop X and the Topical Meeting of the 26th COSPAR Plenary Meeting, Toulouse, France, June 30-July 11, 1986
NASA Technical Reports Server (NTRS)
The present conference on space-based remote sensing of the earth's surface and atmosphere addresses the two broad issues of remote sensing activities of interest to developing countries and the results obtained to date by the International Satellite Cloud Climatology Project, the Earth Radiation Budget Experiment, and the Stratospheric Aerosol and Gas Experiment (SAGE). Attention is given to the remote sensing of environmental factors affecting health, applications of satellite microwave radiometry, earth science missions for the NASA Space Station, and digitally produced Landsat map images. Also discussed are time-accumulated visible and IR histograms used as cloud cover descriptors, the estimation of the radiation budget's sensitivity to cloud variations, monitoring global surface temperature variations using cloud data sets, and an analysis of preliminary SAGE II data on ozone and NO2.
Carter, W. D. (editor); Arking, A. (editor); Mccormick, M. P. (editor); Raschke, E. (editor)
Inversion Method Study on Short Wave Infrared Remote Sensing Data High Temperature Surface Feature Temperature
The short wave infrared remote sensing data element DN value is synthesis reflectance of surface features reflex and the emission energy that the emission energy can be ignored generally in terms of the normal temperature surface features, but emission energy of the high temperature surface feature is close or higher than its reflex energy value, based on this, using the
Pan Jun; Xing Li-xin; Wen Jiu-cheng; Meng Tao; Jiang Li-jun
Sea Ice Surface Temperature Product from the Moderate Resolution Imaging Spectroradiometer (MODIS)
NASA Technical Reports Server (NTRS)
Global sea ice products are produced from the Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS) on board both the Terra and Aqua satellites. Daily sea ice extent and ice-surface temperature (IST) products are available at 1- and 4-km resolution. Validation activities have been undertaken to assess the accuracy of the MODIS IST product at the South Pole station in Antarctica and in the Arctic Ocean using near-surface air-temperature data from a meteorological station and drifting buoys. Results from the study areas show that under clear skies, the MODIS ISTs are very close to those of the near-surface air temperatures with a bias of -1.1 and -1.2 K, and an uncertainty of 1.6 and 1.7 K, respectively. It is shown that the uncertainties would be reduced if the actual temperature of the ice surface were reported instead of the near-surface air temperature. It is not possible to get an accurate IST from MODIS in the presence of even very thin clouds or fog, however using both the Advanced Microwave Scanning Radiometer-EOS (AMSR-E) and the MODIS on the Aqua satellite, it may be possible to develop a relationship between MODIS-derived IST and ice temperature derived from the AMSR-E. Since the AMSR-E measurements are generally unaffected by cloud cover, they may be used to complement the MODIS IST measurements.
Hall, Dorothy K.; Key, Jeffrey R.; Casey, Kimberly A.; Riggs, George A.; Cavalieri, Donald J.
Determination of the surface temperature of a burning powder
An improved method for determining the temperature of a powder combustion surface is proposed. The method is based on the following physical consideration: After extinguishing the powder, the heat accumulated in a relatively small surface layer propagates into the depths of the charge. If the change in temperature at some point within the charge is recorded, this will permit the establishment of a temperature profile and the determination of the combustion surface temperature of the powder at the beginning of the experiment. Thus, direct calorimetry is completely eliminated. Working formulas are obtained on the basis of a simplified plane problem of thermal conductivity for a half space simulating powder specimens after quenching.
Chernov, Iu.V.
The influence of rare-earth ions on the low-temperature thermoluminescence of Bi4Ge3O12
NASA Astrophysics Data System (ADS)
Low-temperature (20-290 K) thermoluminescence spectra of Bi4 Ge3 O12 reveal a range of trapping levels, some of which are common to both undoped and doped material. The emission spectra for undoped and transition-metal-doped Bi4 Ge3 O12 indicate that at low temperatures, intrinsic luminescence centres result in broad-band emission typical of signals from relaxed excitons or possibly excited bismuth ions. For material containing rare-earth ions, the signals are characteristic of the rare-earth dopants, even when the rare-earth ions are present in concentrations as low as 3 ppm. The temperatures of the glow peaks seen at ~54, 105 and 141 K for undoped material are strongly modified by the rare-earth ions. The trapping and recombination sites, monitored by rare-earth emission, are intimately linked, probably within large complex structures. For these three glow peaks the peak temperature varies smoothly with the ionic radii of the rare-earth impurities. These movements are substantial, with changes of up to 50 K, as a function of the rare-earth radii. Of all the rare-earth ions, europium forms the most stable recombination centres. This is probably because the trivalent europium ion is similar in size to the host (bismuth) ion for which it substitutes. Tentative models for trapping sites and thermoluminescence mechanisms are proposed.
Raymond, S. G.; Townsend, P. D.
On The Possible Biological Nature of Climate Stability On Earth: Implications From Study of Temperature Dependence of The Greenhouse Effect
NASA Astrophysics Data System (ADS)
Due to the exponential positive feedback between sea surface temperature and satu- rated water vapour concentration, the dependence of the planetary greenhouse effect on atmospheric water content is critical for stability of a climate with extensive liq- uid hydrosphere. On the basis of the law of energy conservation we develop a simple physically transparent approach to description of radiative transfer in an atmosphere containing greenhouse substances. It is shown that the analytical solution of the equa- tion thus derived coincides with the exact solution of the well-known radiative transfer equation to the accuracy of 20% for all values of atmospheric optical depth. The de- rived equation makes it possible to easily take into account the non-radiative thermal fluxes (convection and latent heat) and obtain an analytical dependence of the green- house effect on atmospheric concentrations of a set of greenhouse substances with arbitrary absorption intervals. The established dependence is used to analyse stabil- ity of the modern climate of Earth. It is shown that the modern value of global mean surface temperature, which corresponds to the liquid state of the terrestrial hydro- sphere, is physically unstable. The observed stability of modern climate over geologi- cal timescales is therefore likely to be due to dynamic singularities in the temperature- dependent behaviour of the greenhouse effect. We quantify these singularities from the empirical global data on greenhouse effect. We hypothesise that such singulari- ties may appear due to controlling functioning of the natural global biota and discuss major arguments in support of this conclusion.
Gorshkov, V.; Makarieva, A.
Martian Meteorites Record Surface Temperatures on Mars
NASA Astrophysics Data System (ADS)
Using published data for argon (Ar) released when Martian meteorites are heated, David Shuster (California Institute of Technology, now at Berkeley Geochronology Center, Berkeley, CA) and Benjamin Weiss (Massachusetts Institute of Technology) show that the nakhlite group of Martian meteorites and unique Martian meteorite ALH 84001 were probably not heated above about 0 degree C for most of their histories. This indicates that the surface of Mars has been cold for almost four billion years. If a warm, wet environment existed on Mars (inferred from previous studies of surface features and geochemical parameters), it occurred before four billion years ago.
Taylor, G. J.
Rare earth chalcogenide Ce3Te4 as high efficiency high temperature thermoelectric material
NASA Astrophysics Data System (ADS)
The electronic band structures of Ce3Te4 have been studied using the first-principles density-functional theory calculations. It is found that the density of states of Ce3Te4 has a very high delta-shaped peak appearing 0.21 eV above the Fermi level, which mainly comes from the f orbital electrons of the rare-earth element Ce. Using the simple theory proposed by Mahan and Sofo, [Proc. Natl. Acad. Sci. U.S.A. 93, 7436 (1996)], we obtain an ideal value of zT=13.5 for Ce3Te4 at T=1200 K, suggesting that the rare-earth chalcogenide Ce3Te4 could be a promising high efficiency high temperature thermoelectric material.
Wang, Xiaochun; Yang, Ronggui; Zhang, Yong; Zhang, Peihong; Xue, Yu
About the temperature distribution in the Earth on it's accumulation stage.
NASA Astrophysics Data System (ADS)
Up to our time there was not a satisfy explanation of dividing process for reservoirs: core and mantle during the period of 10 million years, that result had been achieved using the data of W-Hf isotopic system. Nevertheless there had been exist an estimation for the process of dividing 100 million years. In the paper (Anfilogov, Khachay, 2005) we had suggested a new model of planet of the Earth's group accumulation. Taking into account of energy dissipation of the short-lived radioactive isotopes, first of all 26Al ,in the matter of the germs of the growing proto planets leads to the overestimation of their initial heat state. In the bodies about 100 km, the temperature in the central areas becomes higher than the melting iron temperature, whereas near the surface forms a thin cold envelope. By bodies increasing it's thickness decreases reciprocally to the body radius. The time of that stage rising is equal to 1 million years. A new mechanism of matter differentiation is realized: the relative velocities of the bodies compact with the germ are sufficient for crashing of the upper envelope and for supporting the merging of inner melted especially iron parts. The mass of the growing planet germ is not sufficient for keeping of especially silicate pieces of the envelope. Just on that stage of bodies combining, which arise (100-1000) km can be happen the effective dividing of the W-Hf system between the iron and silicate reservoirs through the period of time about or less than 10 million years. The forming of the core and mantle from that in the most divided reservoirs ends later. By mathematical modelling it is taken into account, that after the inelastic impact of the falling bodies on the germ with the fluid center area a part of pieces of the cold upper envelope because of a bit of the received kinetic energy does not as a whole leave the germ, and forms a so called "cocoon" on the orbit near the parent body. The increase of the density of particles in the "cocoon" leads to some increase of the probability of the impact with the germ that is the increase of the surface density of the matter near the germ, and the velocity of the proto planet growing depends linear from that value and therefore it also grows. Secondly, the account of the obtained dependence of the temperature distribution in the growing small bodies of the proto planet cloud from their masses allowed us quantitatively estimate the valuable contribution of that factor in the heating of the forming planet, which had not been early taken into account. That additional heat on the early stage can be urgently needed for explanation of the thermal evolution of the formed planet. That results had been achieved by support of the grant RFBR 07-05-00395.
Khachay, Yu. V.; Anfilogov, V. N.
Global shortwave energy budget at the earth's surface from ERBE observations
NASA Technical Reports Server (NTRS)
A method is proposed to compute the net solar (shortwave) irradiance at the earth's surface from Earth Radiation Budget Experiment (ERBE) data in the S4 format. The S4 data are monthly averaged broadband planetary albedo collected at selected times during the day. Net surface shortwave irradiance is obtained from the shortwave irradiance incident at the top of the atmosphere (known) by subtracting both the shortwave energy flux reflected by the earth-atmosphere system (measured) and the energy flux absorbed by the atmosphere (modeled). Precalculated atmospheric- and surface-dependent functions that characterize scattering and absorption in the atmosphere are used, which makes the method easily applicable and computationally efficient. Four surface types are distinguished, namely, ocean, vegetation, desert, and snow/ice. Over the tropical Pacific Ocean, the estimates based on ERBE data compare well with those obtained from International Satellite Cloud Climatology Project (ISCCP) B3 data. For the 9 months analyzed the linear correlation coefficient and the standard difference between the two datasets are 0.95 and 14 W/sq m (about 6% of the average shortwave irradiance), respectively, and the bias is 15 W/sq m (higher ERBE values). The bias, a strong function of ISCCP satellite viewing zenith angle, is mostly in the ISCCP-based estimates. Over snow/ice, vegetation, and desert no comparison is made with other satellite-based estimates, but theoretical calculations using the discrete ordinate method suggest that over highly reflective surfaces (snow/ice, desert) the model, which accounts crudely for multiple reflection between the surface and clouds, may substantially overestimate the absorbed solar energy flux at the surface, especially when clouds are optically thick. The monthly surface shortwave irradiance fields produced for 1986 exhibit the main features characteristic of the earth's climate. As found in other studies, our values are generally higher than Esbensen and Kushnir's by as much as 80 W/sq m in the tropical oceans. A cloud parameter, defined as the difference between clear-sky and actual irradiances normalized to top-of-atmosphere clear-sky irradiance, is also examined. This parameter, minimally affected by sun zenith angle, is higher in the midlatitude regions of storm tracks than in the intertropical convergence zone (ITCZ), suggesting that, on average, the higher cloud coverage in midlatitudes is more effective at reducing surface shortwave irradiance than opaque, convective, yet sparser clouds in the ITCZ. Surface albedo estimates are realistic, generally not exceeding 0.06 in the ocean, as high as 0.9 in polar regions, and reaching 0.5 in the Sahara and Arabian deserts.
Breon, Francois-Marie; Frouin, Robert
AQUA AMSR-E Sea Surface Temperature
NASA Astrophysics Data System (ADS)
NASA's AQUA satellite carries the JAXA's Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E). The AQUA satellite was launched in May 2002 into a polar, sun-synchronous orbit at an altitude of 705 km, with a LECT of 1:30 AM/PM. AMSR-E has 12 channels corresponding to 6 frequencies; all except 23.8 GHz measure both vertical and horizontal polarizations. Geophysical retrievals of SST, wind speed, water vapor, cloud liquid water, and rain rates are calculated using a multi-stage linear regression algorithm derived through comprehensive radiative transfer model simulations. SST retrievals are prevented by rain, sun glint, near land emissions, and radio frequency interference due to geostationary satellite broadcasts. Since only a small number of retrievals are unsuccessful, almost complete global coverage is available daily. At high latitudes, where cloud cover regularly prevents infrared observations of SSTs, the microwave observations of SST provide a significant improvement to measurement capabilities. Validation of the datasets through comparison to the global drifting buoy networks yields mean biases of -0.02 K and standard deviations of 0.50 K. AMSR-E SSTs have been widely used for numerical weather prediction, ocean modeling, fisheries, and oceanographic research.
Gentemann, C. L.
Kinetics of surface dissolution: A coupled thermodynamics-climatic approach for Titan and the Earth
NASA Astrophysics Data System (ADS)
Titan, Saturn's major icy moon, like the Earth, possesses large bodies of present liquids on its surface under the form of seas, lakes and rivers, and likely of past liquids in currently empty topographic depressions. Titan's seas and lacustrine depressions strongly differ in shape, which likely suggests a difference in terms of geological formation processes. On the one hand, the seas have dendritic contours, are several hundreds of kilometers in width, and seem to develop in areas with significant reliefs and fluvial networks. On the other hand, lacustrine depressions, be they filled currently or not, are typically isolated, have rounded or lobate contours and seem to grow by coalescence. Their sizes vary from a few kilometers to a few tens of kilometers in diameter, and they seem to develop in relatively flat areas without visible connection with fluvial networks. The depths of the seas and lacustrine depressions have been evaluated to several hundreds of meters for the seas (recent estimates from the Cassini RADAR altimeter echoes analysis over Ligeia Mare indicates a depth of about 170 m), when they are a few hundred/tens of meters for the lacustrine depressions. Given the above morphological settings, several formation mechanisms have been proposed for Titan's lacustrine depressions, the most likely one being associated with the dissolution of the surface, such as what is seen in karstic or karsto-evaporitic areas on Earth. However, due to Titan's surface physical properties (T=90-95 K) and composition, the materials that would be involved in such dissolution processes are exotic. In karstic terrains on Earth, the solvent is water and the solutes are rock minerals (e.g., calcite, dolomite, gypsum, anhydrite and halite). On Titan, the solvent is mainly composed of liquid hydrocarbons (methane and/or ethane) and the solutes are probably made of solid hydrocarbons (acetylene, benzene, butane,...), nitriles (hydrogen cyanide, cyanogen,...), tholins and ices (water, carbon dioxide). With the help of the thermodynamic theory of solid-liquid equilibria, we are able to predict the maximum solubility of Titan's pure solids and Earth's pure minerals in the corresponding relevant liquid. The kinetics of surface dissolution are computed in the model using the estimates of the maximum solubilities associated with a reasonable range of atmospheric precipitation rates estimates for both Titan and the Earth. The comparison between terrestrial and titanian dissolution rates indicates that dissolution should be as significant for the evolution of Titan's surface as it is for Earth's. Quantitative assessment of dissolution rates on Titan will help to constrain the age of its lacustrine depressions.
Cornet, Thomas; Cordier, Daniel; Le Bahers, Tangui; Bourgeois, Olivier; Fleurant, Cyril; Le Mou�lic, St�phane
Possible rainfall reduction through reduced surface temperatures due to overgrazing
NASA Technical Reports Server (NTRS)
Surface temperature reduction in terrain denuded of vegetation (as by overgrazing) is postulated to decrease air convection, reducing cloudiness and rainfall probability during weak meteorological disturbances. By reducing land-sea daytime temperature differences, the surface temperature reduction decreases daytime circulation of thermally driven local winds. The described desertification mechanism, even when limited to arid regions, high albedo soils, and weak meteorological disturbances, can be an effective rainfall reducing process in many areas including most of the Mediterranean lands.
Otterman, J.
World-wide Sea-surface Temperatures.
National Technical Information Service (NTIS)
This technical note contains sea-surface isotherm charts divided into geographical sections for the Atlantic, Pacific, and Indian Oceans as well as North American Lakes and Hudson Bay. Each section is furuther divided into 12 monthly sets of charts, each ...
R. R. Traxler G. L. Wheeler
Higher Flux from the Young Sun as an Explanation for Warm Temperatures for Early Earth and Mars
NASA Technical Reports Server (NTRS)
Observations indicate that the Earth was at least warm enough for liquid water to exist as far back as 4 Gyr ago, namely, as early as half a billion years after the formation of the Earth; in fact, there is evidence suggesting that Earth may have been even warmer then than it is now. These relatively warm temperatures required on early Earth are in apparent contradiction to the dimness of the early Sun predicted by the standard solar models. This problem has generally been explained by assuming that Earth's early atmosphere contained huge amounts of carbon dioxide (CO2), resulting in a large enough greenhouse effect to counteract the effect of a dimmer Sun. However, recent work places an upper limit of 0.04 bar on the partial pressure of CO2 in the period from 2.75 to 2.2 Gyr ago, based on the absence of siderite in paleosols; this casts doubt on the viability of a strong CO2 greenhouse effect on early Earth. The existence of liquid water on early Mars has been even more of a puzzle; even the maximum possible CO2 greenhouse effect cannot yield warm enough Martian surface temperatures. These problems can be resolved simultaneously for both Earth and Mars, if the early Sun was brighter than predicted by the standard solar models. This could be accomplished if the early Sun was slightly more massive than it is now, i.e., if the solar wind was considerably stronger in the past than at present. A slightly more massive young Sun would have left fingerprints on the internal structure of the present Sun. Today, helioseismic observations exist that can measure the internal structure of the Sun with very high precision. The task undertaken here was to compute solar models with the highest precision possible at this time, starting with slightly greater initial masses. These were evolved to the present solar age, where comparisons with the helioseismic observations could be made. Our computations also yielded the time evolution of the solar flux at the planets - a key input to the climates of early Earth and Mars. Early solar mass loss is not the only influence that can alter the internal structure of the present Sun. There are minor uncertainties in the physics of the solar models and in the key observed solar parameters that also affect the present Sun's internal structure. It was therefore imperative to obtain an understanding of the effects of these other uncertainties, in order to disentangle them from the fingerprints that might be left by early solar mass loss. From these considerations, our work was divided into two parts: (1) We first computed the evolution of standard solar models with input parameters varied within their uncertainties, to determine their effect on the observable helioseismic quantities; (2) We then computed non-standard solar models with higher initial masses to test against the helioseismological observations.
Sackmann, I.-Juliana
Solar variability and climate change: Geomagnetic aa index and global surface temperature
NASA Astrophysics Data System (ADS)
During the past �120 years, Earth's surface temperature is correlated with both decadal averages and solar cycle minimum values of the geomagnetic aa index. The correlation with aa minimum values suggests the existence of a long-term (low-frequency) component of solar irradiance that underlies the 11-year cyclic component. Extrapolating the aa-temperature correlations to Maunder Minimum geomagnetic conditions implies that solar forcing can account for �50% or more of the estimated �0.7-1.5�C increase in global surface temperature since the second half of the 17th century. Our analysis is admittedly crude and ignores known contributors to climate change such as warming by anthropogenic greenhouse-gases or cooling by volcanic aerosols. Nevertheless, the general similarity in the time-variation of Earth's surface temperature and the low-frequency or secular component of the aa index over the last �120 years supports other studies that indicate a more significant role for solar variability in climate change on decadal and century time-scales than has previously been supposed. The most recent aa data for the current solar minimum suggest that the long-term component of solar forcing will level off or decline during the coming solar cycle.
Cliver, E. W.; Boriakoff, V.; Feynman, J.
PANIC - A surface science package for the in situ characterization of a near-Earth asteroid
NASA Astrophysics Data System (ADS)
This paper presents the results of a mission concept study for an autonomous micro-scale surface lander also referred to as PANIC - the Pico Autonomous Near-Earth Asteroid In Situ Characterizer. The lander is based on the shape of a regular tetrahedron with an edge length of 35 cm, has a total mass of approximately 12 kg and utilizes hopping as a locomotion mechanism in microgravity. PANIC houses four scientific instruments in its proposed baseline configuration which enable the in situ characterization of an asteroid. It is carried by an interplanetary probe to its target and released to the surface after rendezvous. Detailed estimates of all critical subsystem parameters were derived to demonstrate the feasibility of this concept. The study illustrates that a small, simple landing element is a viable alternative to complex traditional lander concepts, adding a significant science return to any near-Earth asteroid (NEA) mission while meeting tight mass budget constraints.
Schindler, Karsten; Thomas, Cristina A.; Reddy, Vishnu; Weber, Andreas; Gruska, Stefan; Fasoulas, Stefanos
Mesoscale mapping of available solar energy at the earth's surface by use of satellites
NASA Technical Reports Server (NTRS)
A method is presented for use of cloud images in the visual spectrum from the SMS/GOES geostationary satellites to determine the hourly distribution of sunshine on the mesoscale. Cloud coverage and density as a function of time of day and season are evaluated through the use of digital data processing techniques. Seasonal geographic distributions of cloud cover/sunshine are converted to joules of solar radiation received at the earth's surface through relationships developed from long-term measurements of these two parameters at six widely distributed stations. The technique can be used to generate maps showing the geographic distribution of total solar radiation on the mesoscale which is received at the earth's surface.
Hiser, H. W.; Senn, H. V.
A framework for global diurnally-resolved observations of Land Surface Temperature
NASA Astrophysics Data System (ADS)
Land surface temperature (LST) is the radiative skin temperature of the land, and is one of the key parameters in the physics of land-surface processes on regional and global scales. Being a key boundary condition in land surface models, which determine the surface to atmosphere fluxes of heat, water and carbon; thus influencing cloud cover, precipitation and atmospheric chemistry predictions within Global models, the requirement for global diurnal observations of LST is well founded. Earth Observation satellites offer an opportunity to obtain global coverage of LST, with the appropriate exploitation of data from multiple instruments providing a capacity to resolve the diurnal cycle on a global scale. Here we present a framework for the production of global, diurnally resolved, data sets for LST which is a key request from users of LST data. We will show how the sampling of both geostationary and low earth orbit data sets could conceptually be employed to build combined, multi-sensor, pole-to-pole data sets. Although global averages already exist for individual instruments and merging of geostationary based LST is already being addressed operationally (Freitas, et al., 2013), there are still a number of important challenges to overcome. In this presentation, we will consider three of the issues still open in LST remote sensing: 1) the consistency amongst retrievals; 2) the clear-sky bias and its quantification; and 3) merging methods and the propagation of uncertainties. For example, the combined use of both geostationary earth orbit (GEO) and low earth orbit (LEO) data, and both infra-red and microwave data are relatively unexplored but are necessary to make the most progress. Hence this study will suggest what is state-of-the-art and how considerable advances can be made, accounting also for recent improvements in techniques and data quality. The GlobTemperature initiative under the Data User Element of ESA's 4th Earth Observation Envelope Programme (2013-2017), which aims to support the wider uptake of global-scale satellite LST by the research and operational user communities, will be a particularly important element in the development and subsequent provision of global diurnal LST. This new project, with its emphasis on promoting the coherence and openness of interactions within the LST and user communities, will be well placed to deliver appropriate data, engage a wide audience and hence be a key promoter of LST research and development for the LST community. References Freitas, S.C., Trigo, I.F., Macedo, J., Barroso, C., Silva, R., & Perdigao, R., 2013, Land surface temperature from multiple geostationary satellites, International Journal of Remote Sensing, 34, 3051-3068.
Ghent, D.; Remedios, J.; Pinnock, S.
A framework for global diurnally-resolved observations of Land Surface Temperature
NASA Astrophysics Data System (ADS)
Land surface temperature (LST) is the radiative skin temperature of the land, and is one of the key parameters in the physics of land-surface processes on regional and global scales. Being a key boundary condition in land surface models, which determine the surface to atmosphere fluxes of heat, water and carbon; thus influencing cloud cover, precipitation and atmospheric chemistry predictions within Global models, the requirement for global diurnal observations of LST is well founded. Earth Observation satellites offer an opportunity to obtain global coverage of LST, with the appropriate exploitation of data from multiple instruments providing a capacity to resolve the diurnal cycle on a global scale. Here we present a framework for the production of global, diurnally resolved, data sets for LST which is a key request from users of LST data. We will show how the sampling of both geostationary and low earth orbit data sets could conceptually be employed to build combined, multi-sensor, pole-to-pole data sets. Although global averages already exist for individual instruments and merging of geostationary based LST is already being addressed operationally (Freitas, et al., 2013), there are still a number of important challenges to overcome. In this presentation, we will consider three of the issues still open in LST remote sensing: 1) the consistency amongst retrievals; 2) the clear-sky bias and its quantification; and 3) merging methods and the propagation of uncertainties. For example, the combined use of both geostationary earth orbit (GEO) and low earth orbit (LEO) data, and both infra-red and microwave data are relatively unexplored but are necessary to make the most progress. Hence this study will suggest what is state-of-the-art and how considerable advances can be made, accounting also for recent improvements in techniques and data quality. The GlobTemperature initiative under the Data User Element of ESA's 4th Earth Observation Envelope Programme (2013-2017), which aims to support the wider uptake of global-scale satellite LST by the research and operational user communities, will be a particularly important element in the development and subsequent provision of global diurnal LST. References Freitas, S.C., Trigo, I.F., Macedo, J., Barroso, C., Silva, R., & Perdigao, R., 2013, Land surface temperature from multiple geostationary satellites, International Journal of Remote Sensing, 34, 3051-3068.
Ghent, Darren; Remedios, John
Surface fractal dimensions and textural properties of mesoporous alkaline-earth hydroxyapatites
NASA Astrophysics Data System (ADS)
This work examines the surface fractal dimensions (Df) and textural properties of three different alkaline-earth hydroxyapatites. Calcium, strontium and barium hydroxyapatite compounds were successfully synthesized via chemical precipitation method and characterized using X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectrometry, Fourier transform infrared spectroscopy, and N2-physisorption measurements. Surface fractal dimensions were determined using single N2-adsorption/desorption isotherms method to quantify the irregular surface of as-prepared compounds. The obtained materials were also characterized through their surface hydroxyl group content, determined by the mass titration method. It was found that the Df values for the three materials covered the range of 0.77 � 0.04-2.33 � 0.11; these results indicated that the materials tend to have smooth surfaces, except the irregular surface of barium hydroxyapatite. Moreover, regarding the synthesized calcium hydroxyapatite exhibited better textural properties compared with the synthesized strontium and barium hydroxyapatites for adsorbent purposes. However, barium hydroxyapatite shows irregular surface, indicating a high population of active sites across the surface, in comparison with the others studied hydroxyapatites. Finally, the results showed a linear correlation between the surface hydroxyl group content at the external surface of materials and their surface fractal dimensions.
Vilchis-Granados, J.; Granados-Correa, F.; Barrera-D�az, C. E.
Earth-atmosphere system and surface reflectivities in arid regions from LANDSAT multispectral scanner measurements
NASA Technical Reports Server (NTRS)
Programs for computing atmospheric transmission and scattering solar radiation were used to compute the ratios of the Earth-atmosphere system (space) directional reflectivities in the vertical direction to the surface reflectivity, for the four bands of the LANDSAT multispectral scanner (MSS). These ratios are presented as graphs for two water vapor levels, as a function of the surface reflectivity, for various sun elevation angles. Space directional reflectivities in the vertical direction are reported for selected arid regions in Asia, Africa and Central America from the spectral radiance levels measured by the LANDSAT MSS. From these space reflectivities, surface vertical reflectivities were computed applying the pertinent graphs. These surface reflectivities were used to estimate the surface albedo for the entire solar spectrum. The estimated albedos are in the range 0.34-0.52, higher than the values reported by most previous researchers from space measurements, but are consistent with laboratory measurements.
Otterman, J.; Fraser, R. S.
Electrokinetic effect in the near-surface layers of the Earth
The electric field in the near-surface layers of a spherically symmetrical Earth was calculated. This electric field is generated\\u000a by electrokinetic processes in a water-saturated porous medium deformed by lunisolar tides. An exact analytical solution of\\u000a the Frenkel� equations describing electrokinetic phenomena is found. Data of observations of the horizontal components of\\u000a the electric field are processed. The main harmonics
M. B. Gokhberg; N. I. Kolosnitsyn; V. M. Lapshin
Oxidation-resistant reflective surfaces for solar dynamic power generation in near earth orbit
NASA Technical Reports Server (NTRS)
Reflective surfaces for Space Station power generation systems are required to withstand the atomic oxygen-dominated environment of near earth orbit. Thin films of platinum and rhodium, which are corrosion resistant reflective metals, have been deposited by ion beam sputter deposition onto various substrate materials. Solar reflectances were then measured as a function of time of exposure to a RF-generated air plasma.
Gulino, Daniel A.; Egger, Robert A.; Banholzer, William F.
Characterization of surface oxidation on rare-earth Er film x-ray laser target
Oxide growth on rare-earth erbium film at room temperature was quantitatively followed by means of quartz oscillation technique. Structure and chemistry of the oxide layer were characterized by x-ray diffraction and x-ray photoelectron spectroscopy. The humidity in oxidizing environment is found to be the key factor leading to the increase of oxidation rate of the erbium film. The oxide layer
Yonggang Wu; Lingyan Chen; Zhe Zhang; Junming Wei; Shuji Qin; Weixing Tang
Late Quaternary surface circulation in the east equatorial South Atlantic: Evidence from alkenone sea surface temperatures
Angola Basin and Walvis Ridge records of past sea surface temperatures (SST) derived from the alkenone Uk37 index are used to reconstruct the surface circulation in the east equatorial South Atlantic for the last 200,000 years. Comparison of SST estimates from surface sediments between 5� and 20�S with modern SST data suggests that the alkenone temperatures represent annual mean values
Ralph R. Schneider; Peter J. M�ller; G�tz Ruhland
Sea-Surface Temperature and Salinity Mapping from Remote Microwave Radiometric Measurements of Brightness Temperature.
National Technical Information Service (NTIS)
A technique to measure remotely sea surface temperature and salinity was demonstrated with a dual frequency microwave radiometer system. Accuracies in temperature of 1 C and in salinity of part thousand for salinity greater than 5 parts per thousand were ...
C. B. Hans-Juergen B. M. Kendall J. C. Fedors
Compensation for effects of ambient temperature on rare-earth doped fiber optic thermometer
NASA Technical Reports Server (NTRS)
Variations in ambient temperature have a negative effect on the performance of any fiber optic sensing system. A change in ambient temperature may alter the design parameters of fiber optic cables, connectors, sources, detectors, and other fiber optic components and eventually the performance of the entire system. The thermal stability of components is especially important in a system which employs intensity modulated sensors. Several referencing schemes have been developed to account for the variable losses that occur within the system. However, none of these conventional compensating techniques can be used to stabilize the thermal drift of the light source in a system based on the spectral properties of the sensor material. The compensation for changes in ambient temperature becomes especially important in fiber optic thermometers doped with rare earths. Different approaches to solving this problem are searched and analyzed.
Adamovsky, G.; Sotomayor, J. L.; Krasowski, M. J.; Eustace, J. G.
Compensation for effects of ambient temperature on rare-earth doped fiber optic thermometer
NASA Technical Reports Server (NTRS)
Variations in ambient temperature have a negative effect on the performance of any fiber optic sensing system. A change in ambient temperature may alter the design parameters of fiber optic cables, connectors, sources, detectors, and other fiber optic components and eventually the performance of the entire system. The thermal stability of components is especially important in a system which employs intensity modulated sensors. Several referencing schemes have been developed to account for the variable losses that occur within the system. However, none of these conventional compensating techniques can be used to stabilize the thermal drift of the light source in a system based on the spectral properties of the sensor material. The compensation for changes in ambient temperature becomes especially important in fiber optic thermometers doped with rare earths. Different approaches to solving this problem are searched and analyzed.
Adamovsky, G.; Sotomayor, J. L.; Krasowski, M. J.; Eustace, J. G.
Syntheses of Glauconite at Surface Temperatures
Ahstraet--Glauconite has been synthesized at low temperature by precipitation of Fe-hydroxides from Si-, Fe-, Al-, and K-containing solutions under reducing conditions. The compositions favorable for the syn- thesis at 20~ and pH 8.5 are 1 ppm Fe, 0.15 ppm Al, 13 ppm SiO2, 1000 ppm KC1, and 1000 ppm dithionite. The K-content of the solutions must be sufficiently high to
Hermann Harder
Temperature Dependent Erosion of Liquid Metal Surfaces
NASA Astrophysics Data System (ADS)
This presentation summarizes recent experiments conducted in PISCES in the area of the erosion of liquid metals in contact with plasma. Samples of lithium, in both solid and liquid states, have been exposed to plasma bombardment in the PISCES-B device. During plasma exposure, line emission from neutral lithium atoms (670.8 nm) in the plasma can be used to provide information on the erosion behavior of the sample. During low temperature exposures, the loss rate is comparable to that expected from sputtering and at high temperature the loss rate equals the evaporation rate from the liquid. However, in the intermediate temperature regime the material loss rate can exceed, by a factor of ten or more, the predicted loss rate from the combination of physical sputtering and thermal evaporation. This behavior is observed for both liquid lithium and liquid gallium samples exposed to either deuterium or helium plasma, indicating that this effect may be generic to all plasma-liquid metal interactions. Possible explanations for this erosion effect will also be discussed. *Work supported under DOE grant DE-FG03-95ER-54301.
Doerner, R. P.; Baldwin, M.; Grossman, A. A.; Luckhardt, S. C.; Seraydarian, R.; Whyte, D. G.
Land surface temperature derived from the SSM\\/I passive microwave brightness temperatures
Passive microwave brightness temperatures from the Defense Meteorological Space Program Special Sensor Microwave\\/Imager (SSM\\/I) were used to determine surface temperature over land areas in the central plains of the United States. A regression analysis comparing all of the SSM\\/I channels and minimum screen air temperatures (representing the surface temperature) showed good correlations, with root-mean-square errors of 2-3 degC. Pixels containing
M. J. McFarland; R. L. Miller; C. M. U. Neale
About the Influence of the initial Atmosphere on the Earth's Temperature Distribution during it's Accumulation
NASA Astrophysics Data System (ADS)
We suggested a new model for accumulation of planets of the Earth's group [1], which is based on the contemporary results of geochemical analyses, which allow to obtain the concentrations of short living radioactive isotopes of 26Al in the matter of the pre planet cloud [2]. With use of that data new estimations of temperature distribution into the growing planetary pre planetary bodies into the Earth's nebular zone had been obtained. For the further Earth's temperature evolution, as it had been showed by the results of numerical modeling, the main role belongs to the temperature distribution in the forming Earth's core and the existence of a dense and transparent atmosphere. The shadow influence of the initial atmosphere had been researched in the paper [3]. We shall give the main consideration to these problems in that paper. It had been shown in [1], that on the earliest accumulation stage the heat release by the decay of 26Al it is sufficient for forming a central melted area and solid relatively thin mainly silicate upper envelope in the pre planetary body, with dimensions, larger than (50-100) km. The impact velocities on that stage are yet not large, therefore by the bodies impact with these or near dimensions liquid and mainly iron their parts merge, but the masses of the pre planetary bodies are not sufficient to gravitational keeping of silicate parts of the cold solid envelope. On that stage they remain into the nebular zone of the proto planet and the mechanism of matter differentiation for the future core and mantle reservoirs realizes. The process takes place yet in small bodies and is in time to finish during less than 10 million years. The next forming of the core and mantle structure continues according to all known estimations about 100 million years. Because of the merging of inner liquid parts of impacting bodies occur due to inelastic impact, the main part of potential energy transforms into heat. That continues up to that time when the iron core mass increases to the main part of the contemporary mass. The silicate particles of different dimensions remain in the proto planet cloud and in the initial atmosphere, reducing it's transparency and release of the heat radiation. On the finishing stage of the core growing the mass of the pre planetary body is sufficient for keeping of the rising part of the silicate envelope of falling bodies. The matter of the growing planet enriches more and more with a touch of silicates. The impact process of accumulated bodies gradually converts to the mechanism of elastic impact, by which only a small part of kinetic energy transforms into the merging by the pre planet body heat. The atmosphere losses the silicate particles and it's transparency exceeds. It is forming either a non melted mantle, or a mantle with a rising melted layer. That results show that the existence of a dense, nontransparent atmosphere leads to temperature growing in the inner areas of the planet during it's accumulation process. 1.Anfilogov V.N., Khachay Yu.V. A possible variant of matter differentiation on the initial stage of Earth's forming. // DAN. 2005, V. 403, N. 6, 803-806. 2.Merk R.,Breuer D., Spohn T., 2002. Numerical modeling of 26Al - Induced radioactive melting of asteroids concerning accretion, Icarus, 159, 183-191. 3.Hayashi C., Nakazawa K., Mizuno H. Earth's melting due to the blanketing effect of primordial dense atmosphere. // Earth and Plenetary Science Letters. (1979). v. 43, 22-28
Khachay, Y.; Anfilogov, V.; Antipin, A.
Video microscopic high-temperature measurement of surface tension.
In this paper, a micropipette-in-microcapillary method and its experimental setup are described for the study of temperature effects on surface tension. Temperature control within the confined space of a capillary was achieved by coating the outer surface of the housing microcapillary with an electrically conductive, transparent, tin-doped indium oxide (ITO) thin film as a heating jacket. The precision of this technique was discussed according to the comparisons of our results with published reference data for water, n-hexadecane, and n-decane at room temperature. The technique was further used to measure the temperature-dependent surface tension of n-decane between 25�C and 110�C and n-hexadecane from 25�C to 200�C. The results were in excellent agreement with available published values, and also indicated linear decrease rates of surface tension with decreasing temperatures. PMID:23273546
Duan, Yufei; Deshiikan, Srinivasa R; Papadopoulos, Kyriakos D
Temperature-induced collapse of alkaline Earth cation-polyacrylate anion complexes.
Polyacrylate anions are used to inhibit CaCO3 precipitation and may be a promising additive to control formation of inorganic nanoparticles. The origin of this applicability lies in specific interactions between the alkaline earth cations and the carboxylate functions along the polyacrylate chains. In the absence of CO32- anions, these interactions eventually cause precipitation of polyelectrolytes. Extended investigation of dilute sodium polyacrylate solutions approaching this precipitation threshold revealed a dramatic shrinking of the PA coil dimensions once the threshold is reached (Eur. Phys. J. E 2001, 5, 117). Recent isothermal calorimetric titration experiments by Antonietti et al. (Macromolecules 2004, 37, 3444) indicated that the driving force of this precipitation is entropic in nature. In the present work, we investigated the impact of temperature on the structural changes of dissolved polyacrylate chains decorated with alkaline earth cations. To this end, large polyacrylate chains were brought close to the precipitation threshold by the addition of distinct amounts of Ca2+ or Sr2+ cations. The resulting structural intermediates were then subjected to temperature variations in the range of 15 degrees C = T = 40 degrees C, and the accompanying structural changes of the polyacrylate coils were recorded by means of light and neutron scattering. As a major result, we could unambiguously demonstrate that the coils can reversibly be collapsed and extended by increasing and decreasing the temperature, respectively. PMID:17696466
Lages, Sebastian; Schweins, Ralf; Huber, Klaus
Surface temperature changes following the six major volcanic episodes between 1780 and 1980
NASA Astrophysics Data System (ADS)
The effects produced by volcanic eruptions on the surface temperature have been a matter of controversy for decades. The present investigation has the objective to examine volcanic eruptions individually to find out which eruptions have been followed by a cooling and which have not, taking into account possible reasons for this difference. The six volcanic episodes between 1780 and 1980 with the largest dust-veil indexes have been chosen. The variation in mean-annual surface temperature from ten years before to ten years after the eruption are considered. The events selected include the eruptions of Asama and Laki in 1783, Tambora in 1815, Coseguina in 1835, Krakatoa in 1883, Santa Maria, Soufriere, and Pelee in 1902, and Agung in 1963). It is found that, while volcanic eruptions certainly do not cause a warming of the earth's surface, the evidence that they cause cooling is not overly impressive either.
Angell, J. K.; Korshover, J.
Surface temperature variations as measured by the Heat Capacity Mapping Mission
NASA Technical Reports Server (NTRS)
The AEM-1 satellite, the Heat Capacity Mapping Mission, has acquired high-quality thermal infrared data at times of day especially suited for studying the earth's surface and the exchange of heat and moisture with the atmosphere. Selected imagery illustrates the considerable variability of surface temperature in and around cities, in the dry southwestern United States, in the Appalachian Mountains, and in agricultural areas. Through simplifying assumptions, an analytic experience is derived that relates day/night temperature differences to the near-surface layer (thermal inertia) and to meteorological factors. Analysis of the result suggests that, in arid regions, estimates of relative thermal inertia may be inferred, whereas, in agricultural areas, a hydrologic interpretation is possible.
Price, J. C.
Fermi surface nesting and charge-density wave formation in rare-earth tritellurides
The Fermi surface of rare-earth tritellurides (RTe3) is investigated in terms of the nesting-driven charge-density wave formation using positron annihilation and first-principles linear muffin-tin orbital calculations. Fermi surface nesting is revealed as a strong candidate for driving charge-density wave formation in these compounds. The nesting vector obtained from positron annihilation experiments on GdTe3 is determined to be q=(0.28�0.02,0,0)a* (a*=2pi\\/a) ,
J. Laverock; S. B. Dugdale; Zs. Major; M. A. Alam; N. Ru; I. R. Fisher; G. Santi; E. Bruno
Surface temperature variation over Zimbabwe between 1897 and 1993
The surface temperature variation over Zimbabwe, and, Harare and Bulawayo between 1933 and 1993, and, 1897 and 1993 respectively, is investigated. For the national average two significant warm phases are identified, with a net warming of +0.3 to +0.5�C since 1933. Warming occurs in maximum temperature, whereas the mean national temperature cools. The effect of the rainfall pattern on temperature
L. S. Unganai
First-principles modelling of Earth and planetary materials at high pressures and temperatures
NASA Astrophysics Data System (ADS)
Atomic-scale materials modelling based on first-principles quantum mechanics is playing an important role in the science of the Earth and the other planets. We outline the basic theory of this kind of modelling and explain how it can be applied in a variety of different ways to probe the thermodynamics, structure and transport properties of both solids and liquids under extreme conditions. After a summary of the density functional formulation of quantum mechanics and its practical implementation through pseudopotentials, we outline the simplest way of applying first-principles modelling, namely static zero-temperature calculations. We show how calculations of this kind can be compared with static compression experiments to demonstrate the accuracy of first-principles modelling at pressures reached in planetary interiors. Noting that virtually all problems concerning planetary interiors require an understanding of materials at high temperatures as well as high pressures, we then describe how first-principles lattice dynamics gives a powerful way of investigating solids at temperatures not too close to the melting line. We show how such calculations have contributed to important progress, including the recent discovery of the post-perovskite phase of MgSiO3 in the D'' layer at the base of the Earth's mantle. A range of applications of first-principles molecular dynamics are then reviewed, including the properties of metallic hydrogen in Jupiter and Saturn, of water, ammonia and methane in Uranus and Neptune, and of oxides and silicates and solid and liquid iron and its alloys in the Earth's deep interior. Recognizing the importance of phase equilibria throughout the planetary sciences, we review recently developed techniques for the first-principles calculation of solid and liquid free energies, melting curves and chemical potentials of alloys. We show how such calculations have contributed to an improved understanding of the temperature distribution and the chemical composition throughout the Earth's interior. The review concludes with a summary of the present state of the field and with some ideas for future developments.
Gillan, M. J.; Alf�, D.; Brodholt, J.; Vocadlo, L.; Price, G. D.
Doping alkaline-earth: a strategy of stabilizing hexagonal GdF3 at room temperature.
Hexagonal GdF3 is a more efficient phosphor host compared with the traditional orthorhombic form but the hexagonal phase is thermodynamically unstable at room temperature. Herein, we present a strategy to stabilize hexagonal GdF3 by doping with alkaline-earth ions in a mild hydrothermal reaction system. The selection of the dopant, effect of the dopant amount and the mechanism of the phase transition was discussed in detail. The luminescence variation of GdF3:Eu was demonstrated to verify the phase transformation. Furthermore, the upconversion luminescence of the Sr-doped and undoped GdF3:Yb/Er was investigated. PMID:24026018
Zhao, Qi; Shao, Baiqi; L�, Wei; Jia, Yongchao; Lv, Wenzhen; Jiao, Mengmeng; You, Hongpeng
The composition of the Earth's core: constraints on S and Si vs. temperature
NASA Astrophysics Data System (ADS)
The Earth's core is an alloy of iron and a light element such as sulphur, oxygen or silicon. Starting with static equations of state of Fe, Fe 3Si, Fe 7S, Fe 3S and FeS, calculated from density functional theory, we can estimate the core composition as a function of thermal pressure. We can relate the thermal pressure at a given density to temperature using the Mie-Gr�neisen formalism. There is a significant (4%) excess volume of mixing along the Fe-FeS binary at core pressures. Consequently, the density of the Earth's core can be explained using much less sulphur (2.0-8.0 wt%) than that previously estimated. However, the amount of sulphur required is still greater than that expected from the abundance of less volatile elements and suggests that a second light element is needed. The equation of state of Fe 3Si shows that the core can accommodate as much 8.7% Si at geophysically reasonable thermal pressures. A core composition of 7.3% Si and 2.3% S, as proposed by All�gre et al. [10] for a chondritic bulk EarthSi/Mg, implies a thermal pressure of 15 GPa at the core-mantle boundary assuming a -3% density change of melting for Fe. A 15 GPa thermal pressure, in turn, requires a temperature of 3000 K for a Gr�neisen parameter ? = 1.38. At the inner core boundary, a core composition of 7.3% Si and 2.3% S implies a thermal pressure near 35 GPa which, in turn, implies a temperature near 4400 K. Somewhat higher core temperatures would result if the sulphur content were as low as that recently proposed. It appears that a sulphur-depleted Earth with a chondriticMg/Si ratio (with excess Si incorporated into the core) is consistent with the observed density of the core, the calculated equations of state, and the estimated thermal pressures. Finally, the results obtained here completely remove any need to accommodate oxygen in the core; this is consistent with the previously found [14] extreme instability of Fe-FeO alloy phases.
Sherman, David M.
Detection of surface temperature from LANDSAT-7/ETM+
NASA Astrophysics Data System (ADS)
Hiroshima Institute of Tec