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test-economy-bepiehbesa-con03a
test-economy-bepiehbesa-con03b
CAP protects the quality of the food in EU The role of CAP is to produce food at affordable prices while maintaining its quality. By having policies which favour agriculture in Europe it is easier to control the quality of the food, maintain it and also support the diversity of the food produced in EU. [1] The goods imported from developing countries are often not produced under such scrutiny as are those in EU. In EU the quality standards of production are one of the highest – the hygiene, the amount of additives in products – all these are set and controlled by the EU. The result of it is that European citizens eat healthy food of high quality which is still affordable – mainly due to subsidies and payments obtained via CAP. [1] European Commission, 'The Common Agricultural Policy A partnership between Europe and Farmers', 2012,
business economic policy international europe house believes eu should abandon The standards of quality can and are checked for imports. Only food, produced without potentially harmful agents and in a certain way, can be sold on European market. The fact that food was not produced in EU does not mean that food is of lower quality, or that there are fewer checks to ensure their quality. In a recent years there were many cases when the food produced in EU was not what it should be – horse meat scandal in 2013 [1] or scandals in Poland with rotten meat. [2] The CAP and EU are not enough to ascertain the quality of produced food and therefore it is unreasonable to follow this argument. [1] Meikle, James, and McDonald, Henry, 'Cameron tells supermarkets: horsemeat burger scandal unacceptable', theguardian.com, 16 January 2013, [2] UPI, 'Europe's food scandals multiply', 8 March 2013,
293
Sound_reinforcement_system
When the measuring equipment gets old and needs replacing, it often requires re-calibration.
Sound reinforcement system A sound reinforcement system is the combination of microphones , signal processors , amplifiers , and loudspeakers in speaker cabinets all controlled by an audio mixing board that makes live or pre-recorded sounds louder and may also distribute those sounds to a larger or more distant audience . In many situations , a sound reinforcement system is also used to enhance or alter the sound of the sources on the stage , typically by using electronic effects , such as reverb , as opposed to simply amplifying the sources unaltered . A sound reinforcement system for a rock concert in a stadium may be very complex , including hundreds of microphones , complex live sound mixing and signal processing systems , tens of thousands of watts of amplifier power , and multiple loudspeaker arrays , all overseen by a team of audio engineers and technicians . On the other hand , a sound reinforcement system can be as simple as a small public address ( PA ) system , consisting of , for example , a single microphone connected to a 100 watt amplified loudspeaker for a singer-guitarist playing in a small coffeehouse . In both cases , these systems reinforce sound to make it louder or distribute it to a wider audience . Some audio engineers and others in the professional audio industry disagree over whether these audio systems should be called sound reinforcement ( SR ) systems or PA systems . Distinguishing between the two terms by technology and capability is common , while others distinguish by intended use ( e.g. , SR systems are for live event support and PA systems are for reproduction of speech and recorded music in buildings and institutions ) . In some regions or markets , the distinction between the two terms is important , though the terms are considered interchangeable in many professional circles .
2055
Ice_age
Over the past one million years climate cycles ranging from Ice Ages to warmer periods have been caused by changing levels of energy from the sun, planetary alignments and ocean currents.
Ice age An ice age is a period of long-term reduction in the temperature of Earth 's surface and atmosphere , resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers . Within a long-term ice age , individual pulses of cold climate are termed `` glacial periods '' ( or alternatively `` glacials '' or `` glaciations '' or colloquially as `` ice age '' ) , and intermittent warm periods are called `` interglacials '' . In the terminology of glaciology , ice age implies the presence of extensive ice sheets in both northern and southern hemispheres . By this definition , we are in an interglacial period -- the Holocene -- of the ice age . The ice age began 2.6 million years ago at the start of the Pleistocene epoch , because the Greenland , Arctic , and Antarctic ice sheets still exist .
1579
Global_warming
A drop in volcanic activity caused warming.
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
2583
Kyoto_Protocol
"Each unit of CO2 you put into the atmosphere has less and less of a warming impact.
Kyoto Protocol The Kyoto Protocol is an international treaty which extends the 1992 United Nations Framework Convention on Climate Change ( UNFCCC ) that commits State Parties to reduce greenhouse gas emissions , based on the fact that ( a ) global warming exists and ( b ) human-made CO2 emissions have caused it . The Kyoto Protocol was adopted in Kyoto , Japan , on 11 December 1997 and entered into force on 16 February 2005 . There are currently 192 parties ( Canada withdrew effective December 2012 ) to the Protocol . The Kyoto Protocol implemented the objective of the UNFCCC to fight global warming by reducing greenhouse gas concentrations in the atmosphere to `` a level that would prevent dangerous anthropogenic interference with the climate system '' ( Art. 2 ) . The Protocol is based on the principle of common but differentiated responsibilities : it puts the obligation to reduce current emissions on developed countries on the basis that they are historically responsible for the current levels of greenhouse gases in the atmosphere . The Protocol 's first commitment period started in 2008 and ended in 2012 . A second commitment period was agreed on in 2012 , known as the Doha Amendment to the protocol , in which 37 countries have binding targets : Australia , the European Union ( and its 28 member states ) , Belarus , Iceland , Kazakhstan , Liechtenstein , Norway , Switzerland , and Ukraine . Belarus , Kazakhstan and Ukraine have stated that they may withdraw from the Protocol or not put into legal force the Amendment with second round targets . Japan , New Zealand and Russia have participated in Kyoto 's first-round but have not taken on new targets in the second commitment period . Other developed countries without second-round targets are Canada ( which withdrew from the Kyoto Protocol in 2012 ) and the United States ( which has not ratified the Protocol ) . As of July 2016 , 66 states have accepted the Doha Amendment , while entry into force requires the acceptances of 144 states . Of the 37 countries with binding commitments , 7 have ratified . Negotiations were held in the framework of the yearly UNFCCC Climate Change Conferences on measures to be taken after the second commitment period ends in 2020 . This resulted in the 2015 adoption of the Paris Agreement , which is a separate instrument under the UNFCCC rather than an amendment of the Kyoto protocol .
1741
Greenhouse_effect
Volcanoes have had no warming effect in recent global warming - if anything, a cooling effect.
Greenhouse effect The greenhouse effect is the process by which radiation from a planet 's atmosphere warms the planet 's surface to a temperature above what it would be without its atmosphere . If a planet 's atmosphere contains radiatively active gases ( i.e. , greenhouse gases ) the atmosphere will radiate energy in all directions . Part of this radiation is directed towards the surface , warming it . The downward component of this radiation -- that is , the strength of the greenhouse effect -- will depend on the atmosphere 's temperature and on the amount of greenhouse gases that the atmosphere contains . On Earth , the atmosphere is warmed by absorption of infrared thermal radiation from the underlying surface ( heated by the sun ) , absorption of shorter wavelength radiant energy from the sun , and convective heat fluxes from the surface . Greenhouse gases in the atmosphere radiate energy , some of which is directed to the surface and lower atmosphere . The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect . Earth 's natural greenhouse effect is critical to supporting life . Human activities , primarily the burning of fossil fuels and clearing of forests , have intensified the natural greenhouse effect , causing global warming . The mechanism is named after a faulty analogy with the effect of solar radiation passing through glass and warming a greenhouse . The way a greenhouse retains heat is fundamentally different , as a greenhouse works by reducing airflow and retaining warm air inside the structure .
1314
July_1966
Higher temperatures, we're told, will be deadly—killing "thousands to tens of thousands" of Americans
July 1966 The following events occurred in July 1966 :
1604
Global_warming
CO2 increase is natural, not human-caused.
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
3063
James_Delingpole
'Another global warming myth comes crashing down.
James Delingpole James Mark Court Delingpole ( born 6 August 1965 ) is an English columnist and novelist who has written for a number of publications , including the Daily Mail , Daily Express , The Times , The Daily Telegraph , and The Spectator . He is executive editor for the London branch of the Breitbart News Network . He has published several novels and four political books . He describes himself as a libertarian conservative , and has been described as a `` prominent voice of the right '' . He has published articles expressing his belief in the non-existence of significant anthropogenic global warming and his opposition to wind power .
2013
Emissions_trading
U.S. Sen. Ron Johnson voted to let oil and gas companies emit "unlimited carbon pollution into our air"
Emissions trading Emissions trading or cap and trade is a government-mandated , market-based approach to controlling pollution by providing economic incentives for achieving reductions in the emissions of pollutants . In contrast to command-and-control environmental regulations such as best available technology ( BAT ) standards and government subsidies , cap and trade ( CAT ) schemes are a type of flexible environmental regulation that allows organizations to decide how best to meet policy targets . Various countries , states and groups of companies have adopted such trading systems , notably for mitigating climate change . A central authority ( usually a governmental body ) allocates or sells a limited number of permits to discharge specific quantities of a specific pollutant per time period . Polluters are required to hold permits in amount equal to their emissions . Polluters that want to increase their emissions must buy permits from others willing to sell them . Financial derivatives of permits can also be traded on secondary markets . In theory , polluters who can reduce emissions most cheaply will do so , achieving the emission reduction at the lowest cost to society . Cap and trade is meant to provide the private sector with the flexibility required to reduce emissions while stimulating technological innovation and economic growth . There are active trading programs in several air pollutants . For greenhouse gases , which cause climate change , permit units are often called carbon credits . The largest greenhouse gases trading program is the European Union Emission Trading Scheme , which trades primarily in European Union Allowances ( EUAs ) ; the Californian scheme trades in California Carbon Allowances , the New Zealand scheme in New Zealand Units and the Australian scheme in Australian Units . The United States has a national market to reduce acid rain and several regional markets in nitrogen oxides .
305
Effects_of_global_warming
There is no statistical evidence that global warming is intensifying[…] floods
Effects of global warming The effects of global warming are the environmental and social changes caused ( directly or indirectly ) by human emissions of greenhouse gases . There is a scientific consensus that climate change is occurring , and that human activities are the primary driver . Many impacts of climate change have already been observed , including glacier retreat , changes in the timing of seasonal events ( e.g. , earlier flowering of plants ) , and changes in agricultural productivity . Future effects of climate change will vary depending on climate change policies and social development . The two main policies to address climate change are reducing human greenhouse gas emissions ( climate change mitigation ) and adapting to the impacts of climate change . Geoengineering is another policy option . Near-term climate change policies could significantly affect long-term climate change impacts . Stringent mitigation policies might be able to limit global warming ( in 2100 ) to around 2 ° C or below , relative to pre-industrial levels . Without mitigation , increased energy demand and extensive use of fossil fuels might lead to global warming of around 4 ° C. Higher magnitudes of global warming would be more difficult to adapt to , and would increase the risk of negative impacts .
413
Carbon_dioxide
However, since 1998, little warming has occurred while carbon dioxide emissions continue to increase.
Carbon dioxide Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas . As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product . Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas . It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting . Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .
2614
Keeling_Curve
"The Keeling curve, which is widely used to show the increase in CO2 emissions, is based on data from the top of Mount Mauna Loa in Hawaii.
Keeling Curve The Keeling Curve is a graph that plots the ongoing change in concentration of carbon dioxide in Earth 's atmosphere since the 1950s . It is based on continuous measurements taken at the Mauna Loa Observatory in Hawaii that began under the supervision of Charles David Keeling . Keeling 's measurements showed the first significant evidence of rapidly increasing carbon dioxide levels in the atmosphere . Many scientists credit Keeling 's graph with first bringing the world 's attention to the current increase of carbon dioxide in the atmosphere . Charles David Keeling , of Scripps Institution of Oceanography at UC San Diego , was the first person to make frequent regular measurements of the atmospheric carbon dioxide ( CO2 ) concentration , taking readings at the South Pole and in Hawaii from 1958 onwards . Measurements of carbon dioxide concentrations in the atmosphere had been taken prior to the Mauna Loa measurements , but on an ad-hoc basis across a variety of locations . Guy Stewart Callendar had shown a steady increase in concentrations since the 19th century . Keeling had perfected the measurement techniques and observed `` strong diurnal behavior with steady values of about 310 ppm in the afternoon '' at three locations : Big Sur near Monterey , the rain forests of Olympic Peninsula , and high mountain forests in Arizona . By measuring the ratio of two isotopes of carbon , Keeling attributed the diurnal change to respiration from local plants and soils , with afternoon values representative of the `` free atmosphere '' . By 1960 , Keeling and his group had determined that the measurement records from California , Antarctica , and Hawaii were long enough to see not just the diurnal and seasonal variations , but also a year-on-year increase that roughly matched the amount of fossil fuels burned per year . In the article that made him famous , Keeling observed : `` at the South Pole the observed rate of increase is nearly that to be expected from the combustion of fossil fuel '' .
906
Snowball_Earth
Goklany has argued that the rising level of carbon dioxide in the earth's atmosphere 'is currently net beneficial for both humanity and the biosphere generally."
Snowball Earth The Snowball Earth hypothesis proposes that Earth 's surface became entirely or nearly entirely frozen at least once , sometime earlier than 650 Mya ( million years ago ) . Proponents of the hypothesis argue that it best explains sedimentary deposits generally regarded as of glacial origin at tropical palaeolatitudes , and other enigmatic features in the geological record . Opponents of the hypothesis contest the implications of the geological evidence for global glaciation and the geophysical feasibility of an ice - or slush-covered ocean , and emphasize the difficulty of escaping an all-frozen condition . A number of unanswered questions remain , including whether the Earth was a full snowball , or a `` slushball '' with a thin equatorial band of open ( or seasonally open ) water . The snowball Earth episodes occurred before the sudden radiation of multicellular bioforms , known as the Cambrian explosion . The most recent snowball episode may have triggered the evolution of multicellularity . Another , much earlier and longer snowball episode , the Huronian glaciation , which occurred 2400 to 2100 Mya , may have been triggered by the first appearance of oxygen in the atmosphere , the `` Great Oxygenation Event . ''
550
Global_warming
Last year, scientists published evidence that the conditions leading up to "stuck jet streams" are becoming more common, with warming in the Arctic seen as a likely culprit.
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
1947
Mike_Pence
President-elect Trump has selected a climate change skeptic to head the team in charge of the transition between Obama and Trump's Environmental Protection Agencies.
Mike Pence Michael Richard Pence ( born June 7 , 1959 ) is an American politician , lawyer , and the 48th and current Vice President of the United States . He previously served as the 50th Governor of Indiana from 2013 to 2017 . Born and raised in Columbus , Indiana , Pence graduated from Hanover College and earned a law degree from the Indiana University Robert H. McKinney School of Law before entering private practice . After losing two bids for a U.S. congressional seat in 1988 and 1990 , he became a conservative radio and television talk show host from 1994 to 1999 . Pence was elected to the United States Congress in 2000 and represented and in the United States House of Representatives from 2001 to 2013 . He served as the chairman of the House Republican Conference from 2009 to 2011 . Pence positioned himself as a principled ideologue and supporter of the Tea Party movement , noting he was `` a Christian , a conservative , and a Republican , in that order . '' Upon becoming Governor of Indiana in January 2013 , Pence initiated the largest tax cut in Indiana 's history , pushed for more funding for education initiatives , and continued to increase the state 's budget surplus . Pence signed bills intended to restrict abortions , including one that prohibited abortions if the reason for the procedure was the fetus 's race , gender , or disability . Pence stirred several high-profile controversies , including with his signature of the Religious Freedom Restoration Act , for which he encountered fierce resistance from moderate members of his party , the business community , and LGBT advocates . He later signed an additional bill acting as an amendment intended to protect LGBT people . On November 8 , 2016 , Pence was elected as Vice President , after he dropped out of his gubernatorial re-election campaign in July to become the vice presidential running mate for Republican presidential nominee Donald Trump , who went on to win the presidential election .
3004
Year
"The solar system oscillates with a 60-year cycle due to the Jupiter/Saturn three-synodic cycle and to a Jupiter/Saturn beat tidal cycle...
Year A year is the orbital period of the Earth moving in its orbit around the Sun . Due to the Earth 's axial tilt , the course of a year sees the passing of the seasons , marked by changes in weather , the hours of daylight , and , consequently , vegetation and soil fertility . In temperate and subpolar regions around the globe , four seasons are generally recognized : spring , summer , autumn and winter . In tropical and subtropical regions several geographical sectors do not present defined seasons ; but in the seasonal tropics , the annual wet and dry seasons are recognized and tracked . A calendar year is an approximation of the number of days of the Earth 's orbital period as counted in a given calendar . The Gregorian , or modern , calendar , presents its calendar year to be either a common year of 365 days or a leap year of 366 days , as do the Julian calendars ; see below . For the Gregorian calendar the average length of the calendar year ( the mean year ) across the complete leap cycle of 400 years is 365.2425 days . The ISO standard ISO 80000-3 , Annex C , supports the symbol `` a '' ( for Latin annus ) to represent a year of either 365 or 366 days . In English , the abbreviations `` y '' and `` yr '' are commonly used . In astronomy , the Julian year is a unit of time ; it is defined as 365.25 days of exactly seconds ( SI base unit ) , totalling exactly seconds in the Julian astronomical year . The word `` year '' is also used for periods loosely associated with , but not identical to , the calendar or astronomical year , such as the seasonal year , the fiscal year , the academic year , etc. . Similarly , `` year '' can mean the orbital period of any planet : for example , a Martian year or a Venusian year are examples of the time a planet takes to transit one complete orbit . The term can also be used in reference to any long period or cycle , such as the Great Year .
2323
Martian
Now scientists are telling us that Mars is experiencing its own planetary warming: Martian warming.
Martian A Martian is a native inhabitant of the planet Mars . Although the search for evidence of life on Mars continues , many science fiction writers have imagined what extraterrestrial life on Mars might be like . Some writers also use the word Martian to describe a human colonist on Mars .
979
Climate_change_in_Australia
"Warm weather worsened the most recent five-year drought, which included the driest four-year period on record in terms of statewide precipitation.
Climate change in Australia Climate change has been a major issue in Australia since the beginning of the 21st century . In 2013 , the CSIRO released a report stating that Australia is becoming hotter , and that it will experience more extreme heat and longer fire seasons because of climate change . In 2014 , the Bureau of Meteorology released a report on the state of Australia 's climate that highlighted several key points , including the significant increase in Australia 's temperatures ( particularly night-time temperatures ) and the increasing frequency of bush fires , droughts and floods , which have all been linked to climate change . Since the beginning of the 20th century Australia has experienced an increase of nearly 1 ° C in average annual temperatures , with warming occurring at twice the rate over the past 50 years than in the previous 50 years . Recent climate events such as extremely high temperatures and widespread drought have focused government and public attention on the impacts of climate change in Australia . Rainfall in southwestern Australia has decreased by 10 -- 20 % since the 1970s , while southeastern Australia has also experienced a moderate decline since the 1990s . Rainfall patterns are expected to be problematic , as rain has become heavier and infrequent , as well as more common in summer rather than in winter , with little or no uptrend in rainfall in the Western Plateau and the Central Lowlands of Australia . Water sources in the southeastern areas of Australia have depleted due to increasing population in urban areas ( rising demand ) coupled with climate change factors such as persistent prolonged drought ( diminishing supply ) . At the same time , Australia continues to have the highest per capita greenhouse gas emissions . Temperatures in Australia have also risen dramatically since 1910 and nights have become warmer . A carbon tax was introduced in 2011 by the Gillard government in an effort to reduce the impact of climate change and despite some criticism , it successfully reduced Australia 's carbon dioxide emissions , with coal generation down 11 % since 2008 -- 09 . The subsequent Australian Government , elected in 2013 under then Prime Minister Tony Abbott was criticised for being `` in complete denial about climate change '' . Furthermore , the Abbott government repealed the carbon tax on 17 July 2014 in a heavily criticised move . The renewable energy target ( RET ) , launched in 2001 , was heavily modified under Abbott 's government . However , under the government of Malcolm Turnbull , Australia attended the 2015 United Nations Climate Change Conference and adopted the Paris Agreement . This agreement includes a review of emission reduction targets every 5 years from 2020 . The federal government and all state governments ( New South Wales , Victoria , Queensland , South Australia , Western Australia , Tasmania , Northern Territory and the Australian Capital Territory ) have explicitly recognised that climate change is being caused by greenhouse gas emissions , in conformity with the scientific opinion on climate change . Sectors of the population have campaigned against new coal mines and coal-fired power stations , reflecting concerns about the effects of global warming on Australia . The Garnaut Climate Change Review predicted that a net benefit to Australia may be derived by stabilising greenhouse gases in the atmosphere at 450ppm CO2 eq . The per-capita carbon footprint in Australia was rated 12th in the world by PNAS in 2011 , considerably large given the small population of the country .
3048
Carbon_dioxide
There is no question whatsoever that the CO2 increase is human-caused.
Carbon dioxide Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas . As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product . Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas . It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting . Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .
1378
Antarctica
Antarctica is gaining land-based ice, according to a new study by NASA scientists published in the Journal of Glaciology
Antarctica Antarctica ( UK English -LSB- ænˈtɑːktɪkə -RSB- or -LSB- ænˈtɑːtɪkə -RSB- , US English -LSB- æntˈɑːrktɪkə -RSB- ) is Earth 's southernmost continent . It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere , almost entirely south of the Antarctic Circle , and is surrounded by the Southern Ocean . At 14000000 km2 , it is the fifth-largest continent . For comparison , Antarctica is nearly twice the size of Australia . About 98 % of Antarctica is covered by ice that averages 1.9 km in thickness , which extends to all but the northernmost reaches of the Antarctic Peninsula . Antarctica , on average , is the coldest , driest , and windiest continent , and has the highest average elevation of all the continents . Antarctica is a desert , with annual precipitation of only 200 mm ( 8 in ) along the coast and far less inland . The temperature in Antarctica has reached − 89.2 ° C ( − 128.6 ° F ) , though the average for the third quarter ( the coldest part of the year ) is − 63 ° C ( − 81 ° F ) . Anywhere from 1,000 to 5,000 people reside throughout the year at the research stations scattered across the continent . Organisms native to Antarctica include many types of algae , bacteria , fungi , plants , protista , and certain animals , such as mites , nematodes , penguins , seals and tardigrades . Vegetation , where it occurs , is tundra . Although myths and speculation about a Terra Australis ( `` Southern Land '' ) date back to antiquity , Antarctica is noted as the last region on Earth in recorded history to be discovered and colonised by humans , being only first sighted in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny , who sighted the Fimbul ice shelf . The continent , however , remained largely neglected for the rest of the 19th century because of its hostile environment , lack of easily accessible resources , and isolation . In 1895 , the first confirmed landing was conducted by a team of Norwegians . Antarctica is a de facto condominium , governed by parties to the Antarctic Treaty System that have consulting status . Twelve countries signed the Antarctic Treaty in 1959 , and thirty-eight have signed it since then . The treaty prohibits military activities and mineral mining , prohibits nuclear explosions and nuclear waste disposal , supports scientific research , and protects the continent 's ecozone . Ongoing experiments are conducted by more than 4,000 scientists from many nations .
699
Natural_disaster
While volcanic eruptions are natural events, it was the timing of these that had such a noticeable effect on the trend
Natural disaster A natural disaster is a major adverse event resulting from natural processes of the Earth ; examples include floods , hurricanes , tornadoes , volcanic eruptions , earthquakes , tsunamis , and other geologic processes . A natural disaster can cause loss of life or property damage , and typically leaves some economic damage in its wake , the severity of which depends on the affected population 's resilience , or ability to recover and also on the infrastructure available . An adverse event will not rise to the level of a disaster if it occurs in an area without vulnerable population . In a vulnerable area , however , such as Nepal during the 2015 earthquake , an earthquake can have disastrous consequences and leave lasting damage , requiring years to repair .
1296
Urban_heat_island
precipitation from global warming will make the world much greener
Urban heat island An urban heat island ( UHI ) is an urban area or metropolitan area that is significantly warmer than its surrounding rural areas due to human activities . The temperature difference usually is larger at night than during the day , and is most apparent when winds are weak . UHI is most noticeable during the summer and winter . The main cause of the urban heat island effect is from the modification of land surfaces . Waste heat generated by energy usage is a secondary contributor . As a population center grows , it tends to expand its area and increase its average temperature . The less-used term heat island refers to any area , populated or not , which is consistently hotter than the surrounding area . Monthly rainfall is greater downwind of cities , partially due to the UHI . Increases in heat within urban centers increases the length of growing seasons , and decreases the occurrence of weak tornadoes . The UHI decreases air quality by increasing the production of pollutants such as ozone , and decreases water quality as warmer waters flow into area streams and put stress on their ecosystems . Not all cities have a distinct urban heat island . Mitigation of the urban heat island effect can be accomplished through the use of green roofs and the use of lighter-colored surfaces in urban areas , which reflect more sunlight and absorb less heat . There are concerns raised about possible contribution from urban heat islands to global warming . Research on China and India indicates that urban heat island effect contributes to climate warming by about 30 % . On the other hand , one 1999 comparison between urban and rural areas proposed that the urban heat island effects have little influence on global mean temperature trends . Many studies reveal increases in the severity of the effect with the progress of climate change .
2602
An_Inconvenient_Truth
If the public were aware that man-made CO2 is so incredibly small there would be very little belief in a climate disaster ..."
An Inconvenient Truth An Inconvenient Truth is a 2006 American documentary film directed by Davis Guggenheim about former United States Vice President Al Gore 's campaign to educate citizens about global warming via a comprehensive slide show that , by his own estimate made in the film , he has given more than a thousand times . The idea to document his efforts came from producer Laurie David , who saw his presentation at a town-hall meeting on global warming , which coincided with the opening of The Day After Tomorrow . Laurie David was so inspired by Gore 's slide show that she , with producer Lawrence Bender , met with Guggenheim to adapt the presentation into a film . Premiering at the 2006 Sundance Film Festival and opening in New York City and Los Angeles on May 24 , 2006 , the documentary was a critical and box office success , winning two Academy Awards for Best Documentary Feature and Best Original Song . The film grossed $ 24 million in the U.S. and $ 26 million at the international box office , becoming the tenth highest grossing documentary film to date in the United States . Since the film 's release , An Inconvenient Truth has been credited for raising international public awareness of global warming and reenergizing the environmental movement . The documentary has also been included in science curricula in schools around the world , which has spurred some controversy . A sequel to the film , titled An Inconvenient Sequel : Truth to Power , will be released on July 28 , 2017 .
1498
Carbon_dioxide
carbon dioxide has had a minuscule effect on global climate.
Carbon dioxide Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas . As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product . Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas . It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting . Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .
3111
List_of_large-scale_temperature_reconstructions_of_the_last_2,000_years
Ljungqvist's millennial temperature reconstruction was very similar to Moberg et al.
List of large-scale temperature reconstructions of the last 2,000 years This list of large scale temperature reconstructions of the last 2,000 years includes climate reconstructions which have contributed significantly to the modern consensus on the temperature record of the past 2000 years . The instrumental temperature record only covers the last 150 years at a hemispheric or global scale , and reconstructions of earlier periods are based on climate proxies . In an early attempt to show that climate had changed , Hubert Lamb 's 1965 paper generalised from temperature records of central England together with historical , botanical and archeological evidence to produce a qualitative estimate of temperatures in the north Atlantic region . Subsequent quantitative reconstructions used statistical techniques with various climate proxies to produce larger scale reconstructions . Tree ring proxies can give an annual resolution of extratropical regions of the northern hemisphere , and can be statistically combined with other sparser proxies to produce multiproxy hemispherical or global reconstructions . Quantitative reconstructions have consistently shown earlier temperatures below the temperature levels reached in the late 20th century . This pattern as seen in was dubbed the hockey stick graph , and as of 2010 this broad conclusion was supported by more than two dozen reconstructions , using various statistical methods and combinations of proxy records , with variations in how flat the pre-20th century `` shaft '' appears .
2632
Global_warming
At least close to the new spot and to the equator, nothing less than global warming is expected"
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
925
Global_warming
About 120,000 years ago, before the last ice age, the planet went through a natural warm period, with temperatures similar to those expected in coming decades.
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
3105
Global_warming
Global warming theory holds that one of the fingerprints of human-induced global warming is more rapid warming in the lower troposphere than at the surface (James Taylor)
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
1130
El_Niño
The record warm years of 2015 and 2016 were primarily caused by the super El Nino.'"
El Niño El Niño -LSB- ɛl_ˈniːnjoʊ -RSB- ( -LSB- el ˈniɲo -RSB- ) is the warm phase of the El Niño Southern Oscillation ( commonly called ENSO ) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific ( between approximately the International Date Line and 120 ° W ) , including off the Pacific coast of South America . El Niño Southern Oscillation refers to the cycle of warm and cold temperatures , as measured by sea surface temperature , SST , of the tropical central and eastern Pacific Ocean . El Niño is accompanied by high air pressure in the western Pacific and low air pressure in the eastern Pacific . The cool phase of ENSO is called `` La Niña '' with SST in the eastern Pacific below average and air pressures high in the eastern and low in western Pacific . The ENSO cycle , both El Niño and La Niña , cause global changes of both temperatures and rainfall . Developing countries that are dependent upon agriculture and fishing , particularly those bordering the Pacific Ocean , are usually most affected . In American Spanish , the capitalized term `` El Niño '' refers to `` the little boy '' , so named because the pool of warm water in the Pacific near South America is often at its warmest around Christmas . The original name , `` El Niño de Navidad '' , traces its origin centuries back to Peruvian fisherman , who named the weather phenomenon in reference to the newborn Christ . `` La Niña '' , chosen as the ` opposite ' of El Niño , literally translates to `` the little girl '' .
2208
Instrumental_temperature_record
Empirical measurements of the Earth's heat content show the planet is still accumulating heat and global warming is still happening.
Instrumental temperature record The instrumental temperature record provides the temperature of Earth 's climate system from the historical network of in situ measurements of surface air temperatures and ocean surface temperatures . Data are collected at thousands of meteorological stations , buoys and ships around the globe . The longest-running temperature record is the Central England temperature data series , that starts in 1659 . The longest-running quasi-global record starts in 1850 . In recent decades more extensive sampling of ocean temperatures at various depths have begun allowing estimates of ocean heat content but these do not form part of the global surface temperature datasets .
1365
Global_warming_hiatus
Satellite temperature readings going back to 1979 show 1998 was by far the warmest year in the satellite era
Global warming hiatus A global warming hiatus , also sometimes referred to as a global warming pause or a global warming slowdown , is a period of relatively little change in globally averaged surface temperatures . In the current episode of global warming many such 15-year periods appear in the surface temperature record , along with robust evidence of the long-term warming trend ; climate is classically averaged over 30-year periods . Publicity has surrounded claims of a global warming hiatus during the period 1998 -- 2013 . The exceptionally warm El Niño year of 1998 was an outlier from the continuing temperature trend , and so subsequent annual temperatures gave the appearance of a hiatus : by January 2006 , it appeared to some that global warming had stopped or paused . A 2009 study showed that decades without warming were not exceptional , and in 2011 a study showed that if allowances were made for known variability , the rising temperature trend continued unabated . There was increased public interest in 2013 in the run-up to publication of the IPCC Fifth Assessment Report , and despite concerns that a 15-year period was too short to determine a meaningful trend , the IPCC included a section on a hiatus , which it defined as a much smaller increasing linear trend over the 15 years from 1998 to 2012 , than over the 60 years from 1951 to 2012 . Various studies examined possible causes of the short-term slowdown . Even though the overall climate system has continued to accumulate energy due to Earth 's positive energy budget , the available temperature readings at the Earth 's surface indicate slower rates of increase in surface warming than in the prior decade . Since measurements at the top of the atmosphere show that Earth is receiving more energy than it is radiating back into space , the retained energy should be producing warming in the Earth 's climate system . Research reported in July 2015 on an updated NOAA dataset casts doubt on the existence of a hiatus , and it finds no indication of a slowdown even in earlier years . Scientists working on other datasets welcomed this study , though they have expressed the view that the recent warming trend was less than in previous periods of the same length . Subsequently , a detailed study supports the conclusion that warming is continuing , but it also find there was less warming between 2001 and 2010 than climate models had predicted , and that this slowdown might be attributed to short-term variations in the Pacific decadal oscillation ( PDO ) , which was negative during that period . Another review finds `` no substantive evidence '' of a pause in global warming . A statistical study of global temperature data since 1970 concludes that the term ` hiatus ' or ` pause ' is not justified . Independent of these discussions about data and measurements for earlier years , 2015 turned out to be much warmer than any of the earlier years , already before El Niño conditions started . The warmth of 2015 largely ended any remaining scientific credibility of claims that the supposed `` hiatus '' since 1998 had any significance for the long-term warming trend . In January 2017 , a study published in the journal Science Advances cast further doubt on the existence of a recent pause , with more evidence that ocean temperatures have been underestimated . An April 2017 study found the data consistent with a steady warming trend globally since the 1970s , with fluctuations within the expected range of short term variability .
1498
Greenhouse_effect
carbon dioxide has had a minuscule effect on global climate.
Greenhouse effect The greenhouse effect is the process by which radiation from a planet 's atmosphere warms the planet 's surface to a temperature above what it would be without its atmosphere . If a planet 's atmosphere contains radiatively active gases ( i.e. , greenhouse gases ) the atmosphere will radiate energy in all directions . Part of this radiation is directed towards the surface , warming it . The downward component of this radiation -- that is , the strength of the greenhouse effect -- will depend on the atmosphere 's temperature and on the amount of greenhouse gases that the atmosphere contains . On Earth , the atmosphere is warmed by absorption of infrared thermal radiation from the underlying surface ( heated by the sun ) , absorption of shorter wavelength radiant energy from the sun , and convective heat fluxes from the surface . Greenhouse gases in the atmosphere radiate energy , some of which is directed to the surface and lower atmosphere . The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect . Earth 's natural greenhouse effect is critical to supporting life . Human activities , primarily the burning of fossil fuels and clearing of forests , have intensified the natural greenhouse effect , causing global warming . The mechanism is named after a faulty analogy with the effect of solar radiation passing through glass and warming a greenhouse . The way a greenhouse retains heat is fundamentally different , as a greenhouse works by reducing airflow and retaining warm air inside the structure .
1269
Sea
"The oceans, which absorb more than 90% of the extra CO2 pumped into the atmosphere"
Sea A sea is a large body of salt water that is surrounded in whole or in part by land . More broadly , `` the sea '' is the interconnected system of Earth 's salty , oceanic waters -- considered as one global ocean or as several principal oceanic divisions . The sea moderates Earth 's climate and has important roles in the water cycle , carbon cycle , and nitrogen cycle . Although the sea has been traveled and explored since prehistory , the modern scientific study of the sea -- oceanography -- dates broadly to the British Challenger expedition of the 1870s . The sea is conventionally divided into up to five large oceanic sections -- including the International Hydrographic Organization 's four named oceans ( the Atlantic , Pacific , Indian , and Arctic ) and the Southern Ocean ; smaller , second-order sections , such as the Mediterranean , are known as seas . Owing to the present state of continental drift , the Northern Hemisphere is now fairly equally divided between land and sea ( a ratio of about 2:3 ) but the South is overwhelmingly oceanic ( 1:4.7 ) . Salinity in the open ocean is generally in a narrow band around 3.5 % by mass , although this can vary in more landlocked waters , near the mouths of large rivers , or at great depths . About 85 % of the solids in the open sea are sodium chloride . Deep-sea currents are produced by differences in salinity and temperature . Surface currents are formed by the friction of waves produced by the wind and by tides , the changes in local sea level produced by the gravity of the Moon and Sun . The direction of all of these is governed by surface and submarine land masses and by the rotation of the Earth ( the Coriolis effect ) . Former changes in sea levels have left continental shelves , shallow areas in the sea close to land . These nutrient-rich waters teem with life , which provide humans with substantial supplies of food -- mainly fish , but also shellfish , mammals , and seaweed -- which are both harvested in the wild and farmed . The most diverse areas surround great tropical coral reefs . Whaling in the deep sea was once common but whales ' dwindling numbers prompted international conservation efforts and finally a moratorium on most commercial hunting . Oceanography has established that not all life is restricted to the sunlit surface waters : even under enormous depths and pressures , nutrients streaming from hydrothermal vents support their own unique ecosystem . Life may have started there and aquatic microbial mats are generally credited with the oxygenation of Earth 's atmosphere ; both plants and animals first evolved in the sea . The sea is an essential aspect of human trade , travel , mineral extraction , and power generation . This has also made it essential to warfare and left major cities exposed to earthquakes and volcanoes from nearby faults ; powerful tsunami waves ; and hurricanes , typhoons , and cyclones produced in the tropics . This importance and duality has affected human culture , from early sea gods to the epic poetry of Homer to the changes induced by the Columbian Exchange , from burial at sea to Basho 's haikus to hyperrealist marine art , and inspiring music ranging from the shanties in The Complaynt of Scotland to Rimsky-Korsakov 's `` The Sea and Sinbad 's Ship '' to A-mei 's `` Listen to the Sea '' . It is the scene of leisure activities including swimming , diving , surfing , and sailing . However , population growth , industrialization , and intensive farming have all contributed to present-day marine pollution . Atmospheric carbon dioxide is being absorbed in increasing amounts , lowering its pH in a process known as ocean acidification . The shared nature of the sea has made overfishing an increasing problem .
2290
Attribution_of_recent_climate_change
Hypothetically, an increasing solar magnetic field could deflect galactic cosmic rays, which hypothetically seed low-level clouds, thus decreasing the Earth's reflectivity and causing global warming.
Attribution of recent climate change Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent climate changes on Earth , commonly known as ` global warming ' . The effort has focused on changes observed during the period of instrumental temperature record , when records are most reliable ; particularly in the last 50 years , when human activity has grown fastest and observations of the troposphere have become available . The dominant mechanisms are anthropogenic , i.e. , the result of human activity . They are : increasing atmospheric concentrations of greenhouse gases global changes to land surface , such as deforestation increasing atmospheric concentrations of aerosols . There are also natural mechanisms for variation including climate oscillations , changes in solar activity , and volcanic activity . According to the Intergovernmental Panel on Climate Change ( IPCC ) , it is `` extremely likely '' that human influence was the dominant cause of global warming between 1951 and 2010 . The IPCC defines `` extremely likely '' as indicating a probability of 95 to 100 % , based on an expert assessment of all the available evidence . Multiple lines of evidence support attribution of recent climate change to human activities : A basic physical understanding of the climate system : greenhouse gas concentrations have increased and their warming properties are well-established . Historical estimates of past climate changes suggest that the recent changes in global surface temperature are unusual . Computer-based climate models are unable to replicate the observed warming unless human greenhouse gas emissions are included . Natural forces alone ( such as solar and volcanic activity ) can not explain the observed warming . The IPCC 's attribution of recent global warming to human activities is a view shared by the scientific community , and is also supported by 196 other scientific organizations worldwide ( see also : scientific opinion on climate change ) .
971
Arctic_sea_ice_decline
Sea ice has diminished much faster than scientists and climate models anticipated.
Arctic sea ice decline Arctic sea ice decline is the sea ice loss observed in recent decades in the Arctic Ocean . The Intergovernmental Panel on Climate Change ( IPCC ) Fourth Assessment Report states that greenhouse gas forcing is largely , but not wholly , responsible for the decline in Arctic sea ice extent . A study from 2011 suggested that internal variability enhanced the greenhouse gas forced sea ice decline over the last decades . A study from 2007 found the decline to be `` faster than forecasted '' by model simulations . The IPCC Fifth Assessment Report concluded with high confidence that sea ice continues to decrease in extent , and that there is robust evidence for the downward trend in Arctic summer sea ice extent since 1979 . It has been established that the region is at its warmest for at least 40,000 years and the Arctic-wide melt season has lengthened at a rate of 5 days per decade ( from 1979 to 2013 ) , dominated by a later autumn freezeup . Sea ice changes have been identified as a mechanism for polar amplification .
1109
Climate_change_in_the_Arctic
"The chain of events that links the melting Arctic with weather to the south begins with rising global temperatures causing more sea ice to melt.
Climate change in the Arctic The effects of global warming in the Arctic , or climate change in the Arctic include rising temperatures , loss of sea ice , and melting of the Greenland ice sheet with a related cold temperature anomaly , observed in recent years . Potential methane release from the region , especially through the thawing of permafrost and methane clathrates , is also a concern . The Arctic warms twice as fast compared to the rest of the world . The pronounced warming signal , the amplified response of the Arctic to global warming , it is often seen as a leading indicator of global warming . The melting of Greenland 's ice sheet is linked to polar amplification . According to a study published in 2016 , about 0.5 ◦ C of the warming in the Arctic has been attributed to reductions in sulfate aerosols in Europe since 1980 .
1304
The_Washington_Times
in a letter to The Times from Lord Krebs and company, essentially telling the newspaper to stop reporting less-than-negative climate stories.
The Washington Times The Washington Times is an American daily newspaper . It is published as a broadsheet at 3600 New York Avenue NE , Washington , D.C. . The paper covers general interest topics with a particular emphasis on American politics . Its slogan is `` America 's Newspaper '' . One of the first broadsheets in the United States to adopt color photography , its daily edition is distributed throughout the District of Columbia and sections of Maryland and Virginia . A weekly tabloid edition aimed at a national audience is also published . A typical issue includes sections for world and national news , business , politics , editorials and opinion pieces , local news , sports , entertainment , and travel . Periodically , the paper publishes large , 30 -- 40 page special sections devoted to specific policy topics that include reports and commentary from a variety of experts on the subject . Founded on May 17 , 1982 , by Unification Church leader Sun Myung Moon , the Times was owned by News World Communications , an international media conglomerate associated with the church until 2010 , in which Moon and a group of former executives purchased the paper . It is currently owned by diversified conglomerate Operations Holdings , which is a wholly owned subsidiary of the church .
95
Hurricane_Harvey
[climate scientists] say that aspects of the case of Hurricane Harvey suggest global warming is making a bad situation worse.
Hurricane Harvey The name Harvey has been used for five tropical cyclones in the Atlantic Ocean . Hurricane Harvey ( 1981 ) - threatened Bermuda but turned away before striking , no damage . Hurricane Harvey ( 1993 ) - short-lived storm that threatened no land . Tropical Storm Harvey ( 1999 ) - struck Florida , causing $ 15 million in damage . Tropical Storm Harvey ( 2005 ) - earliest eighth-storm formation in the Atlantic Ocean since record-keeping began , breaking the old record set in 1936 by 12 days . Threatened Bermuda . Tropical Storm Harvey ( 2011 ) - record eighth-storm failing to reach hurricane strength , in a single season , since reliable records began . Strong tropical storm that affected parts of Central America . Category : Atlantic hurricane disambiguation pages
2774
Hockey_stick_controversy
Actual reconstructions "diverge" from the instrumental series in the last part of 20th century.
Hockey stick controversy In the hockey stick controversy , the data and methods used in reconstructions of the temperature record of the past 1000 years have been disputed . Reconstructions have consistently shown that the rise in the instrumental temperature record of the past 150 years is not matched in earlier centuries , and the name `` hockey stick graph '' was coined for figures showing a long-term decline followed by an abrupt rise in temperatures . These graphs were publicised to explain the scientific findings of climatology , and in addition to scientific debate over the reconstructions , they have been the topic of political dispute . The issue is part of the global warming controversy and has been one focus of political responses to reports by the Intergovernmental Panel on Climate Change ( IPCC ) . Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doubt on climate science . The use of proxy indicators to get quantitative estimates of the temperature record of past centuries was developed from the 1990s onwards , and found indications that recent warming was exceptional . The reconstruction introduced the `` Composite Plus Scaling '' ( CPS ) method used by most later large-scale reconstructions , and its findings were disputed by Patrick Michaels at the United States House Committee on Science . In 1998 , Michael E. Mann , Raymond S. Bradley and Malcolm K. Hughes developed new statistical techniques to produce ( MBH98 ) , the first eigenvector-based climate field reconstruction ( CFR ) . This showed global patterns of annual surface temperature , and included a graph of average hemispheric temperatures back to 1400 . In ( MBH99 ) the methodology was extended back to 1000 . The term hockey stick was coined by the climatologist Jerry D. Mahlman , to describe the pattern this showed , envisaging a graph that is relatively flat to 1900 as forming an ice hockey stick 's `` shaft '' , followed by a sharp increase corresponding to the `` blade '' . A version of this graph was featured prominently in the 2001 IPCC Third Assessment Report ( TAR ) , along with four other reconstructions supporting the same conclusion . The graph was publicised , and became a focus of dispute for those opposed to the strengthening scientific consensus that late 20th-century warmth was exceptional . Those disputing the graph included Pat Michaels , the George C. Marshall Institute and Fred Singer . A paper by Willie Soon and Sallie Baliunas claiming greater medieval warmth was used by the Bush administration chief of staff Philip Cooney to justify altering the first Environmental Protection Agency Report on the Environment . The paper was quickly dismissed by scientists in the Soon and Baliunas controversy , but on July 28 , Republican Jim Inhofe spoke in the Senate citing it to claim `` that man-made global warming is the greatest hoax ever perpetrated on the American people '' . Later in 2003 , a paper by Steve McIntyre and Ross McKitrick disputing the data used in MBH98 paper was publicised by the George C. Marshall Institute and the Competitive Enterprise Institute . In 2004 , Hans von Storch published criticism of the statistical techniques as tending to underplay variations in earlier parts of the graph , though this was disputed and he later accepted that the effect was very small . In 2005 , McIntyre and McKitrick published criticisms of the principal component analysis methodology as used in MBH98 and MBH99 . The analysis therein was subsequently disputed by published papers , including and , which pointed to errors in the McIntyre and McKitrick methodology . In June 2005 , Rep. Joe Barton launched what Sherwood Boehlert , chairman of the House Science Committee , called a `` misguided and illegitimate investigation '' into the data , methods and personal information of Mann , Bradley and Hughes . At Boehlert 's request , a panel of scientists convened by the National Research Council was set up , which reported in 2006 , supporting Mann 's findings with some qualifications , including agreeing that there were some statistical failings but these had little effect on the result . Barton and U.S. Rep. Ed Whitfield requested Edward Wegman to set up a team of statisticians to investigate , and they supported McIntyre and McKitrick 's view that there were statistical failings , although they did not quantify whether there was any significant effect . They also produced an extensive network analysis which has been discredited by expert opinion and found to have issues of plagiarism . Arguments against the MBH studies were reintroduced as part of the Climatic Research Unit email controversy , but dismissed by eight independent investigations . More than two dozen reconstructions , using various statistical methods and combinations of proxy records , have supported the broad consensus shown in the original 1998 hockey-stick graph , with variations in how flat the pre-20th century `` shaft '' appears . The 2007 IPCC Fourth Assessment Report cited 14 reconstructions , 10 of which covered 1,000 years or longer , to support its strengthened conclusion that it was likely that Northern Hemisphere temperatures during the 20th century were the highest in at least the past 1,300 years . Over a dozen subsequent reconstructions , including Mann et al. 2008 and , have supported these general conclusions .
3046
Carbon_dioxide
There are many lines of evidence which clearly show that the atmospheric CO2 increase is caused by humans.
Carbon dioxide Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas . As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product . Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas . It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting . Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .
2506
IPCC_Third_Assessment_Report
The IPCC confirms that computer modeling predicts the existence of a tropical, mid-troposphere "hot spot" about 10km above the Earth's surface.
IPCC Third Assessment Report The IPCC Third Assessment Report , Climate Change 2001 , is an assessment of available scientific and socio-economic information on climate change by the IPCC . The IPCC was established in 1988 by the United Nations Environment Programme ( UNEP ) and the UN 's World Meteorological Organization ( WMO ) '' ... to assess scientific , technical and socio-economic information relevant for the understanding of climate change , its potential impacts and options for adaptation and mitigation . '' -LSB- IPCC website -RSB- The Third Assessment Report ( TAR ) is the third of a series of assessments ; it has been superseded by the IPCC Fourth Assessment Report ( AR4 ) , released in 2007 . Statements of the IPCC or information from the TAR are often used as a reference showing a scientific consensus on the subject of global warming , although a small minority of scientists take issue with the UN assessments ( see also Global warming controversy and Politics of global warming ) .
1387
Global_warming_controversy
[…] Killing 30 million bats every year in response to dubious claims that global warming might once in a great while kill 100,000 bats makes no sense."
Global warming controversy The global warming controversy concerns the public debate over whether global warming is occurring , how much has occurred in modern times , what has caused it , what its effects will be , whether any action should be taken to curb it , and if so what that action should be . In the scientific literature , there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused by human-induced emissions of greenhouse gases . No scientific body of national or international standing disagrees with this view , though a few organizations with members in extractive industries hold non-committal positions . Disputes over the key scientific facts of global warming are more prevalent in the media than in the scientific literature , where such issues are treated as resolved , and such disputes are more prevalent in the United States than globally . Political and popular debate concerning the existence and cause of climate change includes the reasons for the increase seen in the instrumental temperature record , whether the warming trend exceeds normal climatic variations , and whether human activities have contributed significantly to it . Scientists have resolved these questions decisively in favour of the view that the current warming trend exists and is ongoing , that human activity is the cause , and that it is without precedent in at least 2000 years . Public disputes that also reflect scientific debate include estimates of how responsive the climate system might be to any given level of greenhouse gases ( climate sensitivity ) , how global climate change will play out at local and regional scales , and what the consequences of global warming will be . Global warming remains an issue of widespread political debate , often split along party political lines , especially in the United States . Many of the issues that are settled within the scientific community , such as human responsibility for global warming , remain the subject of politically or economically motivated attempts to downplay , dismiss or deny them -- an ideological phenomenon categorised by academics and scientists as climate change denial . The sources of funding for those involved with climate science -- both supporting and opposing mainstream scientific positions -- have been questioned by both sides . There are debates about the best policy responses to the science , their cost-effectiveness and their urgency . Climate scientists , especially in the United States , have reported official and oil-industry pressure to censor or suppress their work and hide scientific data , with directives not to discuss the subject in public communications . Legal cases regarding global warming , its effects , and measures to reduce it have reached American courts . The fossil fuels lobby has been identified as overtly or covertly supporting efforts to undermine or discredit the scientific consensus on global warming .
2402
Ocean_acidification
Although it has some very important and beneficial effects, CO2 meets the legal and encyclopedic definitions of a "pollutant", and human CO2 emissions pose a threat to public health and welfare.
Ocean acidification Ocean acidification is the ongoing decrease in the pH of the Earth 's oceans , caused by the uptake of carbon dioxide from the atmosphere . Seawater is slightly basic ( meaning pH > 7 ) , and the process in question is a shift towards pH-neutral conditions rather than a transition to acidic conditions ( pH < 7 ) . Ocean alkalinity is not changed by the process , or may increase over long time periods due to carbonate dissolution . An estimated 30 -- 40 % of the carbon dioxide from human activity released into the atmosphere dissolves into oceans , rivers and lakes . To achieve chemical equilibrium , some of it reacts with the water to form carbonic acid . Some of these extra carbonic acid molecules react with a water molecule to give a bicarbonate ion and a hydronium ion , thus increasing ocean acidity ( H + ion concentration ) . Between 1751 and 1996 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14 , representing an increase of almost 35 % in H + ion concentration in the world 's oceans . Earth System Models project that within the last decade ocean acidity exceeded historical analogues and in combination with other ocean biogeochemical changes could undermine the functioning of marine ecosystems and disrupt the provision of many goods and services associated with the ocean . Increasing acidity is thought to have a range of potentially harmful consequences for marine organisms , such as depressing metabolic rates and immune responses in some organisms , and causing coral bleaching . By increasing the presence of free hydrogen ions , each molecule of carbonic acid that forms in the oceans ultimately results in the conversion of two carbonate ions into bicarbonate ions . This net decrease in the amount of carbonate ions available makes it more difficult for marine calcifying organisms , such as coral and some plankton , to form biogenic calcium carbonate , and such structures become vulnerable to dissolution . Ongoing acidification of the oceans threatens food chains connected with the oceans . As members of the InterAcademy Panel , 105 science academies have issued a statement on ocean acidification recommending that by 2050 , global emissions be reduced by at least 50 % compared to the 1990 level . While ongoing ocean acidification is anthropogenic in origin , it has occurred previously in Earth 's history . The most notable example is the Paleocene-Eocene Thermal Maximum ( PETM ) , which occurred approximately 56 million years ago . For reasons that are currently uncertain , massive amounts of carbon entered the ocean and atmosphere , and led to the dissolution of carbonate sediments in all ocean basins . Ocean acidification has been called the `` evil twin of global warming '' and `` the other problem '' .
2678
Carbon_dioxide
Measurements of carbon isotopes and falling oxygen in the atmosphere show that rising carbon dioxide is due to the burning of fossil fuels and cannot be coming from the ocean.
Carbon dioxide Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas . As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product . Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas . It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting . Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .
2531
Ganges
"In 1999 New Scientist reported a comment by the leading Indian glaciologist Syed Hasnain, who said in an email interview with this author that all the glaciers in the central and eastern Himalayas could disappear by 2035.
Ganges The Ganges ( -LSB- ˈɡændʒiːz -RSB- ) , also Ganga ( -LSB- ˈɡəŋɡaː -RSB- ) , is a trans-boundary river of Asia which flows through the nations of India and Bangladesh . The 2525 km river rises in the western Himalayas in the Indian state of Uttarakhand , and flows south and east through the Gangetic Plain of North India into Bangladesh , where it empties into the Bay of Bengal . It is the third largest river in the world by discharge . The Ganges is the most sacred river to Hindus . It is also a lifeline to millions of Indians who live along its course and depend on it for their daily needs . It is worshipped as the goddess Ganga in Hinduism . It has also been important historically , with many former provincial or imperial capitals ( such as Kannauj , Kampilya , Kara , Prayag or Allahabad , Kashi , Pataliputra or Patna , Hajipur , Munger , Bhagalpur , Murshidabad , Baharampur , Nabadwip , Saptagram , Kolkata and Dhaka ) located on its banks . The Ganges was ranked as the fifth most polluted river of the world in 2007 . Pollution threatens not only humans , but also more than 140 fish species , 90 amphibian species and the endangered Ganges river dolphin . The levels of fecal coliform from human waste in the waters of the river near Varanasi are more than 100 times the Indian government 's official limit . The Ganga Action Plan , an environmental initiative to clean up the river , has been a major failure thus far , due to corruption , lack of technical expertise , poor environmental planning , and lack of support from religious authorities .
1874
Climate_change_policy_of_the_United_States
Donald Trump signed an executive order naming climate change as a threat "both to the economy and national security."
Climate change policy of the United States Global climate change was first addressed in United States policy beginning in the early 1960s . The Environmental Protection Agency ( EPA ) defines climate change as `` any significant change in the measures of climate lasting for an extended period of time . '' Essentially , climate change includes major changes in temperature , precipitation , or wind patterns , as well as other effects , that occur over several decades or longer . Climate change policy in the US has transformed rapidly over the past twenty years and is being developed at both the state and federal level . The politics of global warming and climate change have polarized certain political parties and other organizations . This article focuses on climate change policy within the United States , as well as exploring the positions of various parties and the influences on policy making and environmental justice repercussions .
967
Little_Ice_Age
He said: 'We have had five warming cycles since about 900AD, each followed by a dramatic cooling cycle.'
Little Ice Age The Little Ice Age ( LIA ) was a period of cooling that occurred after the Medieval Warm Period . Although it was not a true ice age , the term was introduced into scientific literature by François E. Matthes in 1939 . It has been conventionally defined as a period extending from the 16th to the 19th centuries , but some experts prefer an alternative timespan from about 1300 to about 1850 . Climatologists and historians working with local records no longer expect to agree on either the start or end dates of the period , which varied according to local conditions . The NASA Earth Observatory notes three particularly cold intervals : one beginning about 1650 , another about 1770 , and the last in 1850 , all separated by intervals of slight warming . The Intergovernmental Panel on Climate Change Third Assessment Report considered the timing and areas affected by the Little Ice Age suggested largely-independent regional climate changes rather than a globally-synchronous increased glaciation . At most , there was modest cooling of the Northern Hemisphere during the period . Several causes have been proposed : cyclical lows in solar radiation , heightened volcanic activity , changes in the ocean circulation , variations in Earth 's orbit and axial tilt ( orbital forcing ) , inherent variability in global climate , and decreases in the human population .
2891
Geoid
Wu et al (2010) use a new method to calculate ice sheet mass balance.
Geoid The geoid is the shape that the surface of the oceans would take under the influence of Earth 's gravity and rotation alone , in the absence of other influences such as winds and tides . This surface is extended through the continents ( such as with very narrow hypothetical canals ) . All points on a geoid surface have the same gravitational potential energy ( the sum of gravitational potential energy and centrifugal potential energy ) . The geoid can be defined at any value of gravitational potential such as within the Earth 's crust or far out in space , not just at sea level . The force of gravity acts everywhere perpendicular to the geoid , meaning that plumb lines point perpendicular and water levels parallel to the geoid if only gravity and rotational acceleration were at work . Specifically , the geoid is the equipotential surface that would coincide with the mean ocean surface of Earth if the oceans and atmosphere were in equilibrium , at rest relative to the rotating Earth , and extended through the continents ( such as with very narrow canals ) . According to Gauss , who first described it , it is the `` mathematical figure of Earth '' , a smooth but highly irregular surface whose shape results from the uneven distribution of mass within and on the surface of Earth . It does not correspond to the actual surface of Earth 's crust , but to a surface which can only be known through extensive gravitational measurements and calculations . Despite being an important concept for almost two hundred years in the history of geodesy and geophysics , it has only been defined to high precision since advances in satellite geodesy in the late 20th century . It is often described as the true physical figure of the Earth , in contrast to the idealized geometrical figure of a reference ellipsoid . The surface of the geoid is higher than the reference ellipsoid wherever there is a positive gravity anomaly ( mass excess ) and lower than the reference ellipsoid wherever there is a negative gravity anomaly ( mass deficit ) .
2803
Greenhouse_effect
When we do the calculations and include all radiative forcings and the amount of heat being absorbed by the oceans, it shows that the Earth has warmed almost exactly as much as we would expect.
Greenhouse effect The greenhouse effect is the process by which radiation from a planet 's atmosphere warms the planet 's surface to a temperature above what it would be without its atmosphere . If a planet 's atmosphere contains radiatively active gases ( i.e. , greenhouse gases ) the atmosphere will radiate energy in all directions . Part of this radiation is directed towards the surface , warming it . The downward component of this radiation -- that is , the strength of the greenhouse effect -- will depend on the atmosphere 's temperature and on the amount of greenhouse gases that the atmosphere contains . On Earth , the atmosphere is warmed by absorption of infrared thermal radiation from the underlying surface ( heated by the sun ) , absorption of shorter wavelength radiant energy from the sun , and convective heat fluxes from the surface . Greenhouse gases in the atmosphere radiate energy , some of which is directed to the surface and lower atmosphere . The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect . Earth 's natural greenhouse effect is critical to supporting life . Human activities , primarily the burning of fossil fuels and clearing of forests , have intensified the natural greenhouse effect , causing global warming . The mechanism is named after a faulty analogy with the effect of solar radiation passing through glass and warming a greenhouse . The way a greenhouse retains heat is fundamentally different , as a greenhouse works by reducing airflow and retaining warm air inside the structure .
832
Antarctica
Or the news from Antarctica this past May, when a crack in an ice shelf grew 11 miles in six days, then kept going; the break now has just three miles to go — by the time you read this, it may already have met the open water, where it will drop into the sea one of the biggest icebergs ever, a process known poetically as 'calving.'
Antarctica Antarctica ( UK English -LSB- ænˈtɑːktɪkə -RSB- or -LSB- ænˈtɑːtɪkə -RSB- , US English -LSB- æntˈɑːrktɪkə -RSB- ) is Earth 's southernmost continent . It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere , almost entirely south of the Antarctic Circle , and is surrounded by the Southern Ocean . At 14000000 km2 , it is the fifth-largest continent . For comparison , Antarctica is nearly twice the size of Australia . About 98 % of Antarctica is covered by ice that averages 1.9 km in thickness , which extends to all but the northernmost reaches of the Antarctic Peninsula . Antarctica , on average , is the coldest , driest , and windiest continent , and has the highest average elevation of all the continents . Antarctica is a desert , with annual precipitation of only 200 mm ( 8 in ) along the coast and far less inland . The temperature in Antarctica has reached − 89.2 ° C ( − 128.6 ° F ) , though the average for the third quarter ( the coldest part of the year ) is − 63 ° C ( − 81 ° F ) . Anywhere from 1,000 to 5,000 people reside throughout the year at the research stations scattered across the continent . Organisms native to Antarctica include many types of algae , bacteria , fungi , plants , protista , and certain animals , such as mites , nematodes , penguins , seals and tardigrades . Vegetation , where it occurs , is tundra . Although myths and speculation about a Terra Australis ( `` Southern Land '' ) date back to antiquity , Antarctica is noted as the last region on Earth in recorded history to be discovered and colonised by humans , being only first sighted in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny , who sighted the Fimbul ice shelf . The continent , however , remained largely neglected for the rest of the 19th century because of its hostile environment , lack of easily accessible resources , and isolation . In 1895 , the first confirmed landing was conducted by a team of Norwegians . Antarctica is a de facto condominium , governed by parties to the Antarctic Treaty System that have consulting status . Twelve countries signed the Antarctic Treaty in 1959 , and thirty-eight have signed it since then . The treaty prohibits military activities and mineral mining , prohibits nuclear explosions and nuclear waste disposal , supports scientific research , and protects the continent 's ecozone . Ongoing experiments are conducted by more than 4,000 scientists from many nations .
1465
Carbon_dioxide
Since the beginning of the Industrial Revolution, the acidity of surface ocean waters has increased by about 30 percent.13,14
Carbon dioxide Carbon dioxide ( chemical formula ) is a colorless gas with a density about 60 % higher than that of air ( 1.225 g/L ) that is odorless at normally encountered concentrations . Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms . It occurs naturally in Earth 's atmosphere as a trace gas at a concentration of about 0.04 percent ( 400 ppm ) by volume . Natural sources include volcanoes , hot springs and geysers , and it is freed from carbonate rocks by dissolution in water and acids . Because carbon dioxide is soluble in water , it occurs naturally in groundwater , rivers and lakes , ice caps , glaciers and seawater . It is present in deposits of petroleum and natural gas . As the source of available carbon in the carbon cycle , atmospheric carbon dioxide is the primary carbon source for life on Earth and its concentration in Earth 's pre-industrial atmosphere since late in the Precambrian has been regulated by photosynthetic organisms and geological phenomena . Plants , algae and cyanobacteria use light energy to photosynthesize carbohydrate from carbon dioxide and water , with oxygen produced as a waste product . Carbon dioxide is produced by all aerobic organisms when they metabolize carbohydrates and lipids to produce energy by respiration . It is returned to water via the gills of fish and to the air via the lungs of air-breathing land animals , including humans . Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in bread , beer and winemaking . It is produced by combustion of wood and other organic materials and fossil fuels such as coal , peat , petroleum and natural gas . It is a versatile industrial material , used , for example , as an inert gas in welding and fire extinguishers , as a pressurizing gas in air guns and oil recovery , as a chemical feedstock and in liquid form as a solvent in decaffeination of coffee and supercritical drying . It is added to drinking water and carbonated beverages including beer and sparkling wine to add effervescence . The frozen solid form of , known as `` dry ice '' is used as a refrigerant and as an abrasive in dry-ice blasting . Carbon dioxide is the most significant long-lived greenhouse gas in Earth 's atmosphere . Since the Industrial Revolution anthropogenic emissions - primarily from use of fossil fuels and deforestation - have rapidly increased its concentration in the atmosphere , leading to global warming . Carbon dioxide also causes ocean acidification because it dissolves in water to form carbonic acid .
764
Climate_change_(general_concept)
[…]You can think of global warming as one type of climate change.
Climate change (general concept) Climate variability includes all the variations in the climate that last longer than individual weather events, whereas the term climate change only refers to those variations that persist for a longer period of time, typically decades or more. In the time since the industrial revolution the climate has increasingly been affected by human activities that are causing global warming and climate change.The climate system receives nearly all of its energy from the sun. The climate system also radiates energy to outer space. The balance of incoming and outgoing energy, and the passage of the energy through the climate system, determines Earth\'s energy budget. When the incoming energy is greater than the outgoing energy, earth\'s energy budget is positive and the climate system is warming. If more energy goes out, the energy budget is negative and earth experiences cooling.\nThe energy moving through Earth\'s climate system finds expression in weather, varying on geographic scales and time. Long-term averages and variability of weather in a region constitute the region\'s climate. Such changes can be the result of "internal variability", when natural processes inherent to the various parts of the climate system alter the distribution of energy. Examples include variability in ocean basins such as the Pacific decadal oscillation and Atlantic multidecadal oscillation. Climate variability can also result from external forcing, when events outside of the climate system\'s components nonetheless produce changes within the system. Examples include changes in solar output and volcanism.\nClimate variability has consequences for sea level changes, plant life, and mass extinctions; it also affects human societies.
2390
Reforestation
There may have been regions of Greenland that were 'greener' than today
Reforestation Reforestation is the natural or intentional restocking of existing forests and woodlands that have been depleted , usually through deforestation . Reforestation can be used to rectify or improve the quality of human life by soaking up pollution and dust from the air , rebuild natural habitats and ecosystems , mitigate global warming since forests facilitate biosequestration of atmospheric carbon dioxide , and harvest for resources , particularly timber , but also non-timber forest products . The term reforestation is similar to afforestation , the process of restoring and recreating areas of woodlands or forests that may have existed long ago but were deforested or otherwise removed at some point in the past . Sometimes the term re-afforestation is used to distinguish between the original forest cover and the later re-growth of forest to an area . Forestation is the establishment of forest growth on areas that either had forest or lacked it . Special tools , e.g. tree planting bars , are used to make planting of trees easier and faster .
1093
Ocean_acidification
Ocean acidification is the terrifying threat whereby all that man-made CO2 we've been pumping into the atmosphere may react with the sea to form a sort of giant acid bath.
Ocean acidification Ocean acidification is the ongoing decrease in the pH of the Earth 's oceans , caused by the uptake of carbon dioxide from the atmosphere . Seawater is slightly basic ( meaning pH > 7 ) , and the process in question is a shift towards pH-neutral conditions rather than a transition to acidic conditions ( pH < 7 ) . Ocean alkalinity is not changed by the process , or may increase over long time periods due to carbonate dissolution . An estimated 30 -- 40 % of the carbon dioxide from human activity released into the atmosphere dissolves into oceans , rivers and lakes . To achieve chemical equilibrium , some of it reacts with the water to form carbonic acid . Some of these extra carbonic acid molecules react with a water molecule to give a bicarbonate ion and a hydronium ion , thus increasing ocean acidity ( H + ion concentration ) . Between 1751 and 1996 surface ocean pH is estimated to have decreased from approximately 8.25 to 8.14 , representing an increase of almost 35 % in H + ion concentration in the world 's oceans . Earth System Models project that within the last decade ocean acidity exceeded historical analogues and in combination with other ocean biogeochemical changes could undermine the functioning of marine ecosystems and disrupt the provision of many goods and services associated with the ocean . Increasing acidity is thought to have a range of potentially harmful consequences for marine organisms , such as depressing metabolic rates and immune responses in some organisms , and causing coral bleaching . By increasing the presence of free hydrogen ions , each molecule of carbonic acid that forms in the oceans ultimately results in the conversion of two carbonate ions into bicarbonate ions . This net decrease in the amount of carbonate ions available makes it more difficult for marine calcifying organisms , such as coral and some plankton , to form biogenic calcium carbonate , and such structures become vulnerable to dissolution . Ongoing acidification of the oceans threatens food chains connected with the oceans . As members of the InterAcademy Panel , 105 science academies have issued a statement on ocean acidification recommending that by 2050 , global emissions be reduced by at least 50 % compared to the 1990 level . While ongoing ocean acidification is anthropogenic in origin , it has occurred previously in Earth 's history . The most notable example is the Paleocene-Eocene Thermal Maximum ( PETM ) , which occurred approximately 56 million years ago . For reasons that are currently uncertain , massive amounts of carbon entered the ocean and atmosphere , and led to the dissolution of carbonate sediments in all ocean basins . Ocean acidification has been called the `` evil twin of global warming '' and `` the other problem '' .
1673
Greenhouse_effect
When CO2 was higher in the past, the sun was cooler.
Greenhouse effect The greenhouse effect is the process by which radiation from a planet 's atmosphere warms the planet 's surface to a temperature above what it would be without its atmosphere . If a planet 's atmosphere contains radiatively active gases ( i.e. , greenhouse gases ) the atmosphere will radiate energy in all directions . Part of this radiation is directed towards the surface , warming it . The downward component of this radiation -- that is , the strength of the greenhouse effect -- will depend on the atmosphere 's temperature and on the amount of greenhouse gases that the atmosphere contains . On Earth , the atmosphere is warmed by absorption of infrared thermal radiation from the underlying surface ( heated by the sun ) , absorption of shorter wavelength radiant energy from the sun , and convective heat fluxes from the surface . Greenhouse gases in the atmosphere radiate energy , some of which is directed to the surface and lower atmosphere . The mechanism that produces this difference between the actual surface temperature and the effective temperature is due to the atmosphere and is known as the greenhouse effect . Earth 's natural greenhouse effect is critical to supporting life . Human activities , primarily the burning of fossil fuels and clearing of forests , have intensified the natural greenhouse effect , causing global warming . The mechanism is named after a faulty analogy with the effect of solar radiation passing through glass and warming a greenhouse . The way a greenhouse retains heat is fundamentally different , as a greenhouse works by reducing airflow and retaining warm air inside the structure .
565
Big_data
In looking at Earth's past, scientists can predict what the future will look like
Big data Big data is a term for data sets that are so large or complex that traditional data processing application software is inadequate to deal with them . Challenges include capture , storage , analysis , data curation , search , sharing , transfer , visualization , querying , updating and information privacy . The term `` big data '' often refers simply to the use of predictive analytics , user behavior analytics , or certain other advanced data analytics methods that extract value from data , and seldom to a particular size of data set . `` There is little doubt that the quantities of data now available are indeed large , but that 's not the most relevant characteristic of this new data ecosystem . '' Analysis of data sets can find new correlations to `` spot business trends , prevent diseases , combat crime and so on . '' Scientists , business executives , practitioners of medicine , advertising and governments alike regularly meet difficulties with large data-sets in areas including Internet search , fintech , urban informatics , and business informatics . Scientists encounter limitations in e-Science work , including meteorology , genomics , connectomics , complex physics simulations , biology and environmental research . Data sets grow rapidly - in part because they are increasingly gathered by cheap and numerous information-sensing Internet of things devices such as mobile devices , aerial ( remote sensing ) , software logs , cameras , microphones , radio-frequency identification ( RFID ) readers and wireless sensor networks . The world 's technological per-capita capacity to store information has roughly doubled every 40 months since the 1980s ; , every day 2.5 exabytes ( 2.5 × 1018 ) of data are generated . One question for large enterprises is determining who should own big-data initiatives that affect the entire organization . Relational database management systems and desktop statistics - and visualization-packages often have difficulty handling big data . The work may require `` massively parallel software running on tens , hundreds , or even thousands of servers '' . What counts as `` big data '' varies depending on the capabilities of the users and their tools , and expanding capabilities make big data a moving target . `` For some organizations , facing hundreds of gigabytes of data for the first time may trigger a need to reconsider data management options . For others , it may take tens or hundreds of terabytes before data size becomes a significant consideration . ''
803
IPCC_Fourth_Assessment_Report
The team of climate scientists notes that in failing to predict the warming 'hiatus' in the beginning of the 21st century, the Intergovernmental Panel on Climate Change (IPCC) models overestimated temperature increases…
IPCC Fourth Assessment Report Climate Change 2007 , the Fourth Assessment Report ( AR4 ) of the United Nations Intergovernmental Panel on Climate Change ( IPCC ) , is the fourth in a series of reports intended to assess scientific , technical and socio-economic information concerning climate change , its potential effects , and options for adaptation and mitigation . The report is the largest and most detailed summary of the climate change situation ever undertaken , produced by thousands of authors , editors , and reviewers from dozens of countries , citing over 6,000 peer-reviewed scientific studies . It supersedes the Third Assessment Report ( 2001 ) , and is superseded by the Fifth Assessment Report . The headline findings of the report were : `` warming of the climate system is unequivocal '' , and `` most of the observed increase in global average temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations . ''
419
Regional_effects_of_global_warming
But the heads of small island nations, fearful of rising sea levels, had also asked scientists to examine the effects of 2.7 degrees of warming.
Regional effects of global warming Regional effects of global warming are long-term significant changes in the expected patterns of average weather of a specific region due to global warming . The world average temperature is rising due to the greenhouse effect caused by increasing levels of greenhouse gases , especially carbon dioxide . When the global temperature changes , the changes in climate are not expected to be uniform across the Earth . In particular , land areas change more quickly than oceans , and northern high latitudes change more quickly than the tropics , and the margins of biome regions change faster than do their cores . Regional effects of global warming vary in nature . Some are the result of a generalised global change , such as rising temperature , resulting in local effects , such as melting ice . In other cases , a change may be related to a change in a particular ocean current or weather system . In such cases , the regional effect may be disproportionate and will not necessarily follow the global trend . The increasing temperatures from greenhouse gases have been causing sea levels to rise for many years . There are three major ways in which global warming will make changes to regional climate : melting or forming ice , changing the hydrological cycle ( of evaporation and precipitation ) and changing currents in the oceans and air flows in the atmosphere . The coast can also be considered a region , and will suffer severe impacts from sea level rise .
293
Microphone
When the measuring equipment gets old and needs replacing, it often requires re-calibration.
Microphone A microphone , colloquially nicknamed mic or mike ( -LSB- ˈmaɪk -RSB- ) , is a transducer that converts sound into an electrical signal . Microphones are used in many applications such as telephones , hearing aids , public address systems for concert halls and public events , motion picture production , live and recorded audio engineering , sound recording , two-way radios , megaphones , radio and television broadcasting , and in computers for recording voice , speech recognition , VoIP , and for non-acoustic purposes such as ultrasonic sensors or knock sensors . Several different types of microphone are in use , which employ different methods to convert the air pressure variations of a sound wave to an electrical signal . The most common are the dynamic microphone , which uses a coil of wire suspended in a magnetic field ; the condenser microphone , which uses the vibrating diaphragm as a capacitor plate , and the piezoelectric microphone , which uses a crystal of piezoelectric material . Microphones typically need to be connected to a preamplifier before the signal can be recorded or reproduced .
496
Hurricane_Floyd
Nine years into that 11-year hurricane drought, a NASA scientist computed it as a 1-in-177-year event.
Hurricane Floyd Hurricane Floyd was a very powerful Cape Verde-type hurricane which struck the east coast of the United States . It was the sixth named storm , fourth hurricane , and third major hurricane in the 1999 Atlantic hurricane season . Floyd triggered the third largest evacuation in US history ( behind Hurricane Gustav and Hurricane Rita ) when 2.6 million coastal residents of five states were ordered from their homes as it approached . The Cape Verde-type hurricane formed off the coast of Africa and lasted from September 7 to September 19 , peaking in strength as a very strong Category 4 hurricane -- just 2 mph short of the highest possible rating on the Saffir -- Simpson Hurricane Scale . It was among the largest Atlantic hurricanes of its strength ever recorded . Floyd was once forecast to strike Florida , but turned away . Instead , Floyd struck The Bahamas at peak strength , causing heavy damage . It then paralleled the East Coast of the United States , causing massive evacuations and costly preparations from Florida through the Mid-Atlantic states . The storm weakened significantly , however , before striking the Cape Fear region , North Carolina as a very strong Category 2 hurricane , and caused further damage as it traveled up the Mid-Atlantic region and into New England . The hurricane produced torrential rainfall in Eastern North Carolina , adding more rain to an area hit by Hurricane Dennis just weeks earlier . The rains caused widespread flooding over a period of several weeks ; nearly every river basin in the eastern part of the state exceeded 500-year flood levels . In total , Floyd was responsible for 57 fatalities and $ 6.9 billion ( 1999 USD ; $ USD ) in damage . Due to the destruction , the World Meteorological Organization retired the name Floyd .
2118
Human
Humans are too insignificant to affect global climate
Human Modern humans ( Homo sapiens , primarily ssp . Homo sapiens sapiens ) are the only extant members of Hominina tribe ( or human tribe ) , a branch of the tribe Hominini belonging to the family of great apes . They are characterized by erect posture and bipedal locomotion ; high manual dexterity and heavy tool use compared to other animals ; and a general trend toward larger , more complex brains and societies . Early hominins -- particularly the australopithecines , whose brains and anatomy are in many ways more similar to ancestral non-human apes -- are less often referred to as `` human '' than hominins of the genus Homo . Several of these hominins used fire , occupied much of Eurasia , and gave rise to anatomically modern Homo sapiens in Africa about 200,000 years ago . They began to exhibit evidence of behavioral modernity around 50,000 years ago . In several waves of migration , anatomically modern humans ventured out of Africa and populated most of the world . The spread of humans and their large and increasing population has had a profound impact on large areas of the environment and millions of native species worldwide . Advantages that explain this evolutionary success include a relatively larger brain with a particularly well-developed neocortex , prefrontal cortex and temporal lobes , which enable high levels of abstract reasoning , language , problem solving , sociality , and culture through social learning . Humans use tools to a much higher degree than any other animal , are the only extant species known to build fires and cook their food , and are the only extant species to clothe themselves and create and use numerous other technologies and arts . Humans are uniquely adept at utilizing systems of symbolic communication ( such as language and art ) for self-expression and the exchange of ideas , and for organizing themselves into purposeful groups . Humans create complex social structures composed of many cooperating and competing groups , from families and kinship networks to political states . Social interactions between humans have established an extremely wide variety of values , social norms , and rituals , which together form the basis of human society . Curiosity and the human desire to understand and influence the environment and to explain and manipulate phenomena ( or events ) has provided the foundation for developing science , philosophy , mythology , religion , anthropology , and numerous other fields of knowledge . Though most of human existence has been sustained by hunting and gathering in band societies , increasing numbers of human societies began to practice sedentary agriculture approximately some 10,000 years ago , domesticating plants and animals , thus allowing for the growth of civilization . These human societies subsequently expanded in size , establishing various forms of government , religion , and culture around the world , unifying people within regions to form states and empires . The rapid advancement of scientific and medical understanding in the 19th and 20th centuries led to the development of fuel-driven technologies and increased lifespans , causing the human population to rise exponentially . Today the global human population is estimated by the United Nations to be near billion .
1313
Coral_bleaching
Coral bleaching has devastated 93% of the Great Barrier Reef
Coral bleaching Coral bleaching occurs when coral polyps expel algae that lives inside their tissues . Normally , coral polyps live in an endosymbiotic relationship with the algae and that relationship is crucial for the coral and hence for the health of the whole reef . Bleached corals continue to live . But as the algae provide the coral with 90 % of its energy , after expelling the algae the coral begins to starve . Above-average sea water temperatures caused by global warming have been identified as a leading cause for coral bleaching worldwide . Between 2014 and 2016 , the longest global bleaching events ever were recorded . According to the United Nations Environment Programme , these bleaching events killed coral on an unprecedented scale . In 2016 , bleaching hit 90 percent of coral on the Great Barrier Reef and killed 29 percent of the reef 's coral . In 2017 , the bleaching further expanded to areas of the park that were previously spared , such as the central one . __ TOC __
293
Surveying
When the measuring equipment gets old and needs replacing, it often requires re-calibration.
Surveying Surveying or land surveying is the technique , profession , and science of determining the terrestrial or three-dimensional position of points and the distances and angles between them . A land surveying professional is called a land surveyor . These points are usually on the surface of the Earth , and they are often used to establish land maps and boundaries for ownership , locations like building corners or the surface location of subsurface features , or other purposes required by government or civil law , such as property sales . Surveyors work with elements of geometry , trigonometry , regression analysis , physics , engineering , metrology , programming languages and the law . They use equipment like total stations , robotic total stations , GPS receivers , retroreflectors , 3D scanners , radios , handheld tablets , digital levels , subsurface locators , drones , GIS and surveying software . Surveying has been an element in the development of the human environment since the beginning of recorded history . The planning and execution of most forms of construction require it . It is also used in transport , communications , mapping , and the definition of legal boundaries for land ownership . It is an important tool for research in many other scientific disciplines .
123
Global_catastrophic_risk
the warming is not nearly as great as the climate change computer models have predicted.
Global catastrophic risk A global catastrophic risk is a hypothetical future event that has the potential to damage human well-being on a global scale . Some events could cripple or destroy modern civilization . Any event that could cause human extinction is known as an existential risk . Potential global catastrophic risks include anthropogenic risks ( technology risks , governance risks ) and natural or external risks . Examples of technology risks are hostile artificial intelligence , biotechnology risks , or nanotechnology weapons . Insufficient global governance creates risks in the social and political domain ( potentially leading to a global war with or without a nuclear holocaust , bioterrorism using genetically modified organisms , cyberterrorism destroying critical infrastructures like the electrical grid , or the failure to manage a natural pandemic ) as well as problems and risks in the domain of earth system governance ( with risks resulting from global warming , environmental degradation , mineral resource exhaustion , fossil energy exhaustion , or famine as a result of non-equitable resource distribution , human overpopulation , crop failures and non-sustainable agriculture ) . Examples for non-anthropogenic risks are an asteroid impact event , a supervolcanic eruption , a lethal gamma-ray burst , a geomagnetic storm destroying all electronic equipment , natural long-term climate change , or extraterrestrial life impacting life on Earth .
2857
Friction
Weather is chaotic because air is light, it has low friction and viscosity, it expands strongly when in contact with hot surfaces and it conducts heat poorly.
Friction Friction is the force resisting the relative motion of solid surfaces , fluid layers , and material elements sliding against each other . There are several types of friction : Dry friction resists relative lateral motion of two solid surfaces in contact . Dry friction is subdivided into static friction ( `` stiction '' ) between non-moving surfaces , and kinetic friction between moving surfaces . Fluid friction describes the friction between layers of a viscous fluid that are moving relative to each other . Lubricated friction is a case of fluid friction where a lubricant fluid separates two solid surfaces . Skin friction is a component of drag , the force resisting the motion of a fluid across the surface of a body . Internal friction is the force resisting motion between the elements making up a solid material while it undergoes deformation . When surfaces in contact move relative to each other , the friction between the two surfaces converts kinetic energy into thermal energy ( that is , it converts work to heat ) . This property can have dramatic consequences , as illustrated by the use of friction created by rubbing pieces of wood together to start a fire . Kinetic energy is converted to thermal energy whenever motion with friction occurs , for example when a viscous fluid is stirred . Another important consequence of many types of friction can be wear , which may lead to performance degradation or damage to components . Friction is a component of the science of tribology . Friction is desirable and important in supplying traction to facilitate motion on land . Most land vehicles rely on friction for acceleration , deceleration and changing direction . Sudden reductions in traction can cause loss of control and accidents . Friction is not itself a fundamental force . Dry friction arises from a combination of inter-surface adhesion , surface roughness , surface deformation , and surface contamination . The complexity of these interactions makes the calculation of friction from first principles impractical and necessitates the use of empirical methods for analysis and the development of theory . Friction is a non-conservative force - work done against friction is path dependent . In the presence of friction , some energy is always lost in the form of heat . Thus mechanical energy is not conserved .
1211
Externality
"climate economists see a positive externality, not a negative one, from the human influence on climate.
Externality In economics , an externality is the cost or benefit that affects a party who did not choose to incur that cost or benefit . Economists often urge governments to adopt policies that `` internalize '' an externality , so that costs and benefits will affect mainly parties who choose to incur them . For example , manufacturing activities that cause air pollution impose health and clean-up costs on the whole society , whereas the neighbors of an individual who chooses to fire-proof his home may benefit from a reduced risk of a fire spreading to their own houses . If external costs exist , such as pollution , the producer may choose to produce more of the product than would be produced if the producer were required to pay all associated environmental costs . Because responsibility or consequence for self-directed action lies partly outside the self , an element of externalization is involved . If there are external benefits , such as in public safety , less of the good may be produced than would be the case if the producer were to receive payment for the external benefits to others . For the purpose of these statements , overall cost and benefit to society is defined as the sum of the imputed monetary value of benefits and costs to all parties involved . Thus , unregulated markets in goods or services with significant externalities generate prices that do not reflect the full social cost or benefit of their transactions ; such markets are therefore inefficient .
1652
Global_warming
The strong CO2 effect has been observed by many different measurements.
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
1831
Koch_Industries
(Koch Industries) is among the worst in toxic air pollution in the entire United States ... and churns out more climate-changing greenhouse gases than oil giants Chevron, Shell and Valero.
Koch Industries Koch Industries , Inc. . -LSB- ˈkoʊk -RSB- is an American multinational corporation based in Wichita , Kansas , United States , with subsidiaries involved in manufacturing , trading , and investments . It was founded as Wood River Oil and Refining Company in 1940 , and later as Rock Island Oil & Refining Company . Koch also owns Invista , Georgia-Pacific , Molex , Flint Hills Resources , Koch Pipeline , Koch Fertilizer , Koch Minerals , Matador Cattle Company and recently Guardian Industries . Koch companies are involved in industries such as the manufacturing , refining , and distribution of petroleum , chemicals , energy , fiber , intermediates and polymers , minerals , fertilizers , pulp and paper , chemical technology equipment , ranching , finance , commodities trading , and other ventures and investments . The firm employs about 60,000 people in the United States and another 40,000 in 59 other countries . In 2013 -- 2015 , Forbes listed it as the second largest privately held company in the United States ( after Cargill ) , with an annual revenue of $ 115 billion , down from the largest in 2006 . If Koch Industries were a public company in 2013 , it would have ranked 17 in the Fortune 500 . Fred C. Koch , after whom Koch Industries , Inc. is named , co-founded the company in 1940 and developed an innovative crude oil refining process . His sons , Charles Koch , chairman of the board and chief executive officer , and David Koch , executive vice president , are principal owners of the company after they bought out their brothers , Frederick and William `` Bill '' Koch , for $ 1.1 billion in 1983 . Charles and David Koch each own 42 % of Koch Industries . Charles has stated that the company would go public `` over my dead body '' .
2618
Tipping_points_in_the_climate_system
It fails to explain how we can have short-term positive feedback and long-term negative feedback.
Tipping points in the climate system A tipping point in the climate system is a threshold that, when exceeded, can lead to large changes in the state of the system. Potential tipping points have been identified in the physical climate system, in impacted ecosystems, and sometimes in both. For instance, feedback from the global carbon cycle is a driver for the transition between glacial and interglacial periods, with orbital forcing providing the initial trigger. Earth's geologic temperature record includes many more examples of geologically rapid transitions between different climate states.Climate tipping points are of particular interest in reference to concerns about global warming in the modern era. Possible tipping point behaviour has been identified for the global mean surface temperature by studying self-reinforcing feedbacks and the past behavior of Earth's climate system. Self-reinforcing feedbacks in the carbon cycle and planetary reflectivity could trigger a cascading set of tipping points that lead the world into a hothouse climate state.Large-scale components of the Earth system that may pass a tipping point have been referred to as tipping elements. Tipping elements are found in the Greenland and Antarctic ice sheets, possibly causing tens of meters of sea level rise. These tipping points are not always abrupt. For example, at some level of temperature rise the melt of a large part of the Greenland ice sheet and/or West Antarctic Ice Sheet will become inevitable; but the ice sheet itself may persist for many centuries. Some tipping elements, like the collapse of ecosystems, are irreversible.
3007
Ice_age
There seems to be evidence for a link between solar activity and water levels.
Ice age An ice age is a period of long-term reduction in the temperature of Earth 's surface and atmosphere , resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers . Within a long-term ice age , individual pulses of cold climate are termed `` glacial periods '' ( or alternatively `` glacials '' or `` glaciations '' or colloquially as `` ice age '' ) , and intermittent warm periods are called `` interglacials '' . In the terminology of glaciology , ice age implies the presence of extensive ice sheets in both northern and southern hemispheres . By this definition , we are in an interglacial period -- the Holocene -- of the ice age . The ice age began 2.6 million years ago at the start of the Pleistocene epoch , because the Greenland , Arctic , and Antarctic ice sheets still exist .
689
Arctic_sea_ice_decline
The heat extremes were especially pervasive in the Arctic, with temperatures in the fall running 20 to 30 degrees Fahrenheit above normal across large stretches of the Arctic Ocean.
Arctic sea ice decline Arctic sea ice decline is the sea ice loss observed in recent decades in the Arctic Ocean . The Intergovernmental Panel on Climate Change ( IPCC ) Fourth Assessment Report states that greenhouse gas forcing is largely , but not wholly , responsible for the decline in Arctic sea ice extent . A study from 2011 suggested that internal variability enhanced the greenhouse gas forced sea ice decline over the last decades . A study from 2007 found the decline to be `` faster than forecasted '' by model simulations . The IPCC Fifth Assessment Report concluded with high confidence that sea ice continues to decrease in extent , and that there is robust evidence for the downward trend in Arctic summer sea ice extent since 1979 . It has been established that the region is at its warmest for at least 40,000 years and the Arctic-wide melt season has lengthened at a rate of 5 days per decade ( from 1979 to 2013 ) , dominated by a later autumn freezeup . Sea ice changes have been identified as a mechanism for polar amplification .
1638
Ice_age
Worry about global warming impacts in the next 100 years, not an ice age in over 10,000 years.
Ice age An ice age is a period of long-term reduction in the temperature of Earth 's surface and atmosphere , resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers . Within a long-term ice age , individual pulses of cold climate are termed `` glacial periods '' ( or alternatively `` glacials '' or `` glaciations '' or colloquially as `` ice age '' ) , and intermittent warm periods are called `` interglacials '' . In the terminology of glaciology , ice age implies the presence of extensive ice sheets in both northern and southern hemispheres . By this definition , we are in an interglacial period -- the Holocene -- of the ice age . The ice age began 2.6 million years ago at the start of the Pleistocene epoch , because the Greenland , Arctic , and Antarctic ice sheets still exist .
591
Global_warming_controversy
But it is part of a long list of studies from independent teams (as this interactive graphic shows), using a variety of methods that take account of critical challenges, all of which conclude that climate models exhibit too much sensitivity to greenhouse gases.
Global warming controversy The global warming controversy concerns the public debate over whether global warming is occurring , how much has occurred in modern times , what has caused it , what its effects will be , whether any action should be taken to curb it , and if so what that action should be . In the scientific literature , there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused by human-induced emissions of greenhouse gases . No scientific body of national or international standing disagrees with this view , though a few organizations with members in extractive industries hold non-committal positions . Disputes over the key scientific facts of global warming are more prevalent in the media than in the scientific literature , where such issues are treated as resolved , and such disputes are more prevalent in the United States than globally . Political and popular debate concerning the existence and cause of climate change includes the reasons for the increase seen in the instrumental temperature record , whether the warming trend exceeds normal climatic variations , and whether human activities have contributed significantly to it . Scientists have resolved these questions decisively in favour of the view that the current warming trend exists and is ongoing , that human activity is the cause , and that it is without precedent in at least 2000 years . Public disputes that also reflect scientific debate include estimates of how responsive the climate system might be to any given level of greenhouse gases ( climate sensitivity ) , how global climate change will play out at local and regional scales , and what the consequences of global warming will be . Global warming remains an issue of widespread political debate , often split along party political lines , especially in the United States . Many of the issues that are settled within the scientific community , such as human responsibility for global warming , remain the subject of politically or economically motivated attempts to downplay , dismiss or deny them -- an ideological phenomenon categorised by academics and scientists as climate change denial . The sources of funding for those involved with climate science -- both supporting and opposing mainstream scientific positions -- have been questioned by both sides . There are debates about the best policy responses to the science , their cost-effectiveness and their urgency . Climate scientists , especially in the United States , have reported official and oil-industry pressure to censor or suppress their work and hide scientific data , with directives not to discuss the subject in public communications . Legal cases regarding global warming , its effects , and measures to reduce it have reached American courts . The fossil fuels lobby has been identified as overtly or covertly supporting efforts to undermine or discredit the scientific consensus on global warming .
1017
Global_warming_controversy
Our children and grandchildren will look back on the climate deniers and ask how they could have sacrificed the planet for the sake of cheap fossil fuel energy, when the cost of inaction exceeds the cost of a transition to a low-carbon economy,' Watson said.
Global warming controversy The global warming controversy concerns the public debate over whether global warming is occurring , how much has occurred in modern times , what has caused it , what its effects will be , whether any action should be taken to curb it , and if so what that action should be . In the scientific literature , there is a strong consensus that global surface temperatures have increased in recent decades and that the trend is caused by human-induced emissions of greenhouse gases . No scientific body of national or international standing disagrees with this view , though a few organizations with members in extractive industries hold non-committal positions . Disputes over the key scientific facts of global warming are more prevalent in the media than in the scientific literature , where such issues are treated as resolved , and such disputes are more prevalent in the United States than globally . Political and popular debate concerning the existence and cause of climate change includes the reasons for the increase seen in the instrumental temperature record , whether the warming trend exceeds normal climatic variations , and whether human activities have contributed significantly to it . Scientists have resolved these questions decisively in favour of the view that the current warming trend exists and is ongoing , that human activity is the cause , and that it is without precedent in at least 2000 years . Public disputes that also reflect scientific debate include estimates of how responsive the climate system might be to any given level of greenhouse gases ( climate sensitivity ) , how global climate change will play out at local and regional scales , and what the consequences of global warming will be . Global warming remains an issue of widespread political debate , often split along party political lines , especially in the United States . Many of the issues that are settled within the scientific community , such as human responsibility for global warming , remain the subject of politically or economically motivated attempts to downplay , dismiss or deny them -- an ideological phenomenon categorised by academics and scientists as climate change denial . The sources of funding for those involved with climate science -- both supporting and opposing mainstream scientific positions -- have been questioned by both sides . There are debates about the best policy responses to the science , their cost-effectiveness and their urgency . Climate scientists , especially in the United States , have reported official and oil-industry pressure to censor or suppress their work and hide scientific data , with directives not to discuss the subject in public communications . Legal cases regarding global warming , its effects , and measures to reduce it have reached American courts . The fossil fuels lobby has been identified as overtly or covertly supporting efforts to undermine or discredit the scientific consensus on global warming .
2577
Coral_reef
"Three recent articles give us reason to question the alarmists' claims that coral reefs are in deep trouble due to the buildup of greenhouse gases." (World Climate Report)
Coral reef Coral reefs are diverse underwater ecosystems held together by calcium carbonate structures secreted by corals . Coral reefs are built by colonies of tiny animals found in marine waters that contain few nutrients . Most coral reefs are built from stony corals , which in turn consist of polyps that cluster in groups . The polyps belong to a group of animals known as Cnidaria , which also includes sea anemones and jellyfish . Unlike sea anemones , corals secrete hard carbonate exoskeletons which support and protect the coral polyps . Most reefs grow best in warm , shallow , clear , sunny and agitated waters . Often called `` rainforests of the sea '' , shallow coral reefs form some of the most diverse ecosystems on Earth . They occupy less than 0.1 % of the world 's ocean surface , about half the area of France , yet they provide a home for at least 25 % of all marine species , including fish , mollusks , worms , crustaceans , echinoderms , sponges , tunicates and other cnidarians . Paradoxically , coral reefs flourish even though they are surrounded by ocean waters that provide few nutrients . They are most commonly found at shallow depths in tropical waters , but deep water and cold water corals also exist on smaller scales in other areas . Coral reefs deliver ecosystem services to tourism , fisheries and shoreline protection . The annual global economic value of coral reefs is estimated between US$ 29.8-375 billion . However , coral reefs are fragile ecosystems , partly because they are very sensitive to water temperature . They are under threat from climate change , oceanic acidification , blast fishing , cyanide fishing for aquarium fish , sunscreen use , overuse of reef resources , and harmful land-use practices , including urban and agricultural runoff and water pollution , which can harm reefs by encouraging excess algal growth .
3127
Science
"Skeptics hope that Postma's alternative thermal model will lead to the birth of a new climatology, one that actually follows the laws of physics and properly physical modeling techniques...
Science Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe . Contemporary science is typically subdivided into the natural sciences , which study the material universe ; the social sciences , which study people and societies ; and the formal sciences , which study logic and mathematics . The formal sciences are often excluded as they do not depend on empirical observations . Disciplines which use science , like engineering and medicine , may also be considered to be applied sciences . From classical antiquity through the 19th century , science as a type of knowledge was more closely linked to philosophy than it is now , and in the Western world the term `` natural philosophy '' once encompassed fields of study that are today associated with science , such as astronomy , medicine , and physics . However , during the Islamic Golden Age foundations for the scientific method were laid by Ibn al-Haytham in his Book of Optics . While the classification of the material world by the ancient Indians and Greeks into air , earth , fire and water was more philosophical , medieval Middle Easterns used practical and experimental observation to classify materials . In the 17th and 18th centuries , scientists increasingly sought to formulate knowledge in terms of physical laws . Over the course of the 19th century , the word `` science '' became increasingly associated with the scientific method itself as a disciplined way to study the natural world . It was during this time that scientific disciplines such as biology , chemistry , and physics reached their modern shapes . That same time period also included the origin of the terms `` scientist '' and `` scientific community '' , the founding of scientific institutions , and the increasing significance of their interactions with society and other aspects of culture .
2966
World_energy_consumption
Over the three years from 1979 to 1982 when CO2 emissions were decreasing due to the rapid increase in the price of oil that drastically reduced consumption, there was no change in the rate of increase in atmospheric concentration of CO2 proving that humans were not the primary source for the increase in concentration.'
World energy consumption World energy consumption is the total energy used by the entire human civilization . Typically measured per year , it involves all energy harnessed from every energy source applied towards humanity 's endeavours across every single industrial and technological sector , across every country . It does not include energy from food , and the extent to which direct biomass burning has been accounted for is poorly documented . Being the power source metric of civilization , World Energy Consumption has deep implications for humanity 's socio-economic-political sphere . Institutions such as the International Energy Agency ( IEA ) , the U.S. Energy Information Administration ( EIA ) , and the European Environment Agency record and publish energy data periodically . Improved data and understanding of World Energy Consumption may reveal systemic trends and patterns , which could help frame current energy issues and encourage movement towards collectively useful solutions . Closely related to energy consumption is the concept of total primary energy supply ( TPES ) , which - on a global level - is the sum of energy production minus storage changes . Since changes of energy storage over the year are minor , TPES values can be used as an estimator for energy consumption . However , TPES ignores conversion efficiency , overstating forms of energy with poor conversion efficiency ( e.g. coal , gas and nuclear ) and understating forms already accounted for in converted forms ( e.g. photovoltaic or hydroelectricity ) . The IEA estimates that , in 2013 , total primary energy supply ( TPES ) was 1.575 × 1017 Wh ( = 157.5 PWh , 5.67 × 1020 joules , or 13,541 Mtoe ) . From 2000 -- 2012 coal was the source of energy with the largest growth . The use of oil and natural gas also had considerable growth , followed by hydropower and renewable energy . Renewable energy grew at a rate faster than any other time in history during this period . The demand for nuclear energy decreased , in part due to nuclear disasters ( e.g. Three Mile Island 1979 , Chernobyl 1986 , and Fukushima 2011 ) . In 2011 , expenditures on energy totalled over 6 trillion USD , or about 10 % of the world gross domestic product ( GDP ) . Europe spends close to one-quarter of the world 's energy expenditures , North America close to 20 % , and Japan 6 % .
2580
Greenhouse_gas
Volcanoes emit around 0.3 billion tonnes of CO2 per year.
Greenhouse gas A greenhouse gas ( abbrev . GHG ) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range . This process is the fundamental cause of the greenhouse effect . The primary greenhouse gases in Earth 's atmosphere are water vapor , carbon dioxide , methane , nitrous oxide , and ozone . Without greenhouse gases , the average temperature of Earth 's surface would be about -18 ° C , rather than the present average of 15 ° C . In the Solar System , the atmospheres of Venus , Mars and Titan also contain gases that cause a greenhouse effect . Human activities since the beginning of the Industrial Revolution ( taken as the year 1750 ) have produced a 40 % increase in the atmospheric concentration of carbon dioxide , from 280 ppm in 1750 to 406 ppm in early 2017 . This increase has occurred despite the uptake of a large portion of the emissions by various natural `` sinks '' involved in the carbon cycle . Anthropogenic carbon dioxide emissions ( i.e. , emissions produced by human activities ) come from combustion of fossil fuels , principally coal , oil , and natural gas , along with deforestation , soil erosion and animal agriculture . It has been estimated that if greenhouse gas emissions continue at the present rate , Earth 's surface temperature could exceed historical values as early as 2047 , with potentially harmful effects on ecosystems , biodiversity and the livelihoods of people worldwide . Recent estimates suggest that on the current emissions trajectory the Earth could pass a threshold of 2 ° C global warming , which the United Nations ' IPCC designated as the upper limit to avoid `` dangerous '' global warming , by 2036 .
2805
Sea_ice
Arctic sea ice loss is three times greater than Antarctic sea ice gain, and the amount of solar energy absorbed by the Earth is increasing as a result.
Sea ice Sea ice arises as seawater freezes . Because ice is less dense than water , it floats on the ocean 's surface ( as does fresh water ice , which has an even lower density ) . Sea ice covers about 7 % of the Earth 's surface and about 12 % of the world 's oceans . Much of the world 's sea ice is enclosed within the polar ice packs in the Earth 's polar regions : the Arctic ice pack of the Arctic Ocean and the Antarctic ice pack of the Southern Ocean . Polar packs undergo a significant yearly cycling in surface extent , a natural process upon which depends the Arctic ecology , including the ocean 's ecosystems . Due to the action of winds , currents and temperature fluctuations , sea ice is very dynamic , leading to a wide variety of ice types and features . Sea ice may be contrasted with icebergs , which are chunks of ice shelves or glaciers that calve into the ocean . Depending on location , sea ice expanses may also incorporate icebergs .
949
Antarctica
Under the most ambitious scenarios, they found a strong likelihood that Antarctica would remain fairly stable."
Antarctica Antarctica ( UK English -LSB- ænˈtɑːktɪkə -RSB- or -LSB- ænˈtɑːtɪkə -RSB- , US English -LSB- æntˈɑːrktɪkə -RSB- ) is Earth 's southernmost continent . It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere , almost entirely south of the Antarctic Circle , and is surrounded by the Southern Ocean . At 14000000 km2 , it is the fifth-largest continent . For comparison , Antarctica is nearly twice the size of Australia . About 98 % of Antarctica is covered by ice that averages 1.9 km in thickness , which extends to all but the northernmost reaches of the Antarctic Peninsula . Antarctica , on average , is the coldest , driest , and windiest continent , and has the highest average elevation of all the continents . Antarctica is a desert , with annual precipitation of only 200 mm ( 8 in ) along the coast and far less inland . The temperature in Antarctica has reached − 89.2 ° C ( − 128.6 ° F ) , though the average for the third quarter ( the coldest part of the year ) is − 63 ° C ( − 81 ° F ) . Anywhere from 1,000 to 5,000 people reside throughout the year at the research stations scattered across the continent . Organisms native to Antarctica include many types of algae , bacteria , fungi , plants , protista , and certain animals , such as mites , nematodes , penguins , seals and tardigrades . Vegetation , where it occurs , is tundra . Although myths and speculation about a Terra Australis ( `` Southern Land '' ) date back to antiquity , Antarctica is noted as the last region on Earth in recorded history to be discovered and colonised by humans , being only first sighted in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny , who sighted the Fimbul ice shelf . The continent , however , remained largely neglected for the rest of the 19th century because of its hostile environment , lack of easily accessible resources , and isolation . In 1895 , the first confirmed landing was conducted by a team of Norwegians . Antarctica is a de facto condominium , governed by parties to the Antarctic Treaty System that have consulting status . Twelve countries signed the Antarctic Treaty in 1959 , and thirty-eight have signed it since then . The treaty prohibits military activities and mineral mining , prohibits nuclear explosions and nuclear waste disposal , supports scientific research , and protects the continent 's ecozone . Ongoing experiments are conducted by more than 4,000 scientists from many nations .
2712
Antarctica
The news of expanding Antarctic sea ice stole headlines from global warming alarmists who asserted Arctic sea ice had reached its lowest extent since 1979.'
Antarctica Antarctica ( UK English -LSB- ænˈtɑːktɪkə -RSB- or -LSB- ænˈtɑːtɪkə -RSB- , US English -LSB- æntˈɑːrktɪkə -RSB- ) is Earth 's southernmost continent . It contains the geographic South Pole and is situated in the Antarctic region of the Southern Hemisphere , almost entirely south of the Antarctic Circle , and is surrounded by the Southern Ocean . At 14000000 km2 , it is the fifth-largest continent . For comparison , Antarctica is nearly twice the size of Australia . About 98 % of Antarctica is covered by ice that averages 1.9 km in thickness , which extends to all but the northernmost reaches of the Antarctic Peninsula . Antarctica , on average , is the coldest , driest , and windiest continent , and has the highest average elevation of all the continents . Antarctica is a desert , with annual precipitation of only 200 mm ( 8 in ) along the coast and far less inland . The temperature in Antarctica has reached − 89.2 ° C ( − 128.6 ° F ) , though the average for the third quarter ( the coldest part of the year ) is − 63 ° C ( − 81 ° F ) . Anywhere from 1,000 to 5,000 people reside throughout the year at the research stations scattered across the continent . Organisms native to Antarctica include many types of algae , bacteria , fungi , plants , protista , and certain animals , such as mites , nematodes , penguins , seals and tardigrades . Vegetation , where it occurs , is tundra . Although myths and speculation about a Terra Australis ( `` Southern Land '' ) date back to antiquity , Antarctica is noted as the last region on Earth in recorded history to be discovered and colonised by humans , being only first sighted in 1820 by the Russian expedition of Fabian Gottlieb von Bellingshausen and Mikhail Lazarev on Vostok and Mirny , who sighted the Fimbul ice shelf . The continent , however , remained largely neglected for the rest of the 19th century because of its hostile environment , lack of easily accessible resources , and isolation . In 1895 , the first confirmed landing was conducted by a team of Norwegians . Antarctica is a de facto condominium , governed by parties to the Antarctic Treaty System that have consulting status . Twelve countries signed the Antarctic Treaty in 1959 , and thirty-eight have signed it since then . The treaty prohibits military activities and mineral mining , prohibits nuclear explosions and nuclear waste disposal , supports scientific research , and protects the continent 's ecozone . Ongoing experiments are conducted by more than 4,000 scientists from many nations .
1307
Great_Barrier_Reef
a new study by scientists at the Australian Research Council finds that the ongoing bleaching event is mainly due to human-caused global warming, and that if global warming proceeds as currently expected, "large parts" of the Great Barrier Reef could die by the mid-2030s.
Great Barrier Reef The Great Barrier Reef is the world 's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over 2300 km over an area of approximately 344400 km2 . The reef is located in the Coral Sea , off the coast of Queensland , Australia . The Great Barrier Reef can be seen from outer space and is the world 's biggest single structure made by living organisms . This reef structure is composed of and built by billions of tiny organisms , known as coral polyps . It supports a wide diversity of life and was selected as a World Heritage Site in 1981 . CNN labelled it one of the seven natural wonders of the world . The Queensland National Trust named it a state icon of Queensland . A large part of the reef is protected by the Great Barrier Reef Marine Park , which helps to limit the impact of human use , such as fishing and tourism . Other environmental pressures on the reef and its ecosystem include runoff , climate change accompanied by mass coral bleaching , and cyclic population outbreaks of the crown-of-thorns starfish . According to a study published in October 2012 by the Proceedings of the National Academy of Sciences , the reef has lost more than half its coral cover since 1985 . The Great Barrier Reef has long been known to and used by the Aboriginal Australian and Torres Strait Islander peoples , and is an important part of local groups ' cultures and spirituality . The reef is a very popular destination for tourists , especially in the Whitsunday Islands and Cairns regions . Tourism is an important economic activity for the region , generating over AUD$ 3 billion per year . In November 2014 , Google launched Google Underwater Street View in 3D of the Great Barrier Reef . A March 2016 report stated that coral bleaching was more widespread than previously thought , seriously affecting the northern parts of the reef as a result of warming ocean temperatures . In October 2016 , Outside published an obituary for the reef ; the article was criticized for being premature and hindering efforts to bolster the resilience of the reef . In March 2017 , the journal Nature published a paper showing that huge sections of a 800-kilometre ( 500 mi ) stretch in the northern part of the reef had died in the course of 2016 due to high water temperatures , an event that the authors put down to the effects of global climate change .
1205
Global_warming
"In 2009, then-British Prime Minister Gordon Brown predicted that the world had only 50 days to save the planet from global warming.
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
1312
St._Louis
A World Heritage site, it is currently under assault from unusually hot ocean temperatures,"
St. Louis St. Louis '' ' ( -LSB- seɪnt_ˈluːɪs -RSB- ) is an independent city and major U.S. port in the state of Missouri , built along the western bank of the Mississippi River , on the border with Illinois . The city had an estimated 2016 population of 311,404 , and is the cultural and economic center of the Greater St. Louis area ( home to 2,916,447 people ) , making it the largest metropolitan area in Missouri and the 19th-largest in the United States . Prior to European settlement , the area was a major regional center of Native American Mississippian culture . The city of St. Louis was founded in 1764 by French fur traders Pierre Laclède and Auguste Chouteau , and named after Louis IX of France . In 1764 , following France 's defeat in the Seven Years ' War , the area was ceded to Spain and retroceded back to France in 1800 . In 1803 , the United States acquired the territory as part of the Louisiana Purchase . During the 19th century , St. Louis developed as a major port on the Mississippi River . In the 1870 Census , St. Louis was ranked as the 4th-largest city in the United States . It separated from St. Louis County in 1877 , becoming an independent city and limiting its own political boundaries . In 1904 , it hosted the Louisiana Purchase Exposition and the Summer Olympics . The economy of metro St. Louis relies on service , manufacturing , trade , transportation of goods , and tourism . Its metro area is home to major corporations , including Anheuser-Busch , Express Scripts , Centene , Boeing Defense , Emerson , Energizer , Panera , Enterprise , Peabody Energy , Ameren , Ralcorp , Monsanto , Scottrade , Edward Jones , Go Jet , Purina and Sigma-Aldrich . This city has also become known for its growing medical , pharmaceutical and research presence . St. Louis has 2 professional sports teams : the St. Louis Cardinals of Major League Baseball and the St. Louis Blues of the National Hockey League . The city is commonly identified with the 630 ft tall Gateway Arch in Downtown St. Louis .
138
Scientific_consensus_on_climate_change
As a result, half of the people surveyed around the world last year said they thought climate change would make humanity extinct.
Scientific consensus on climate change There is currently a strong scientific consensus that the Earth is warming and that this warming is mainly caused by human activities. This consensus is supported by various studies of scientists' opinions and by position statements of scientific organizations, many of which explicitly agree with the Intergovernmental Panel on Climate Change (IPCC) synthesis reports. Nearly all actively publishing climate scientists (97–98%) support the consensus on anthropogenic climate change, and the remaining 2% of contrarian studies either cannot be replicated or contain errors.
2123
Sun
Tree-rings diverge from temperature after 1960
Sun The Sun is the star at the center of the Solar System . It is a nearly perfect sphere of hot plasma , with internal convective motion that generates a magnetic field via a dynamo process . It is by far the most important source of energy for life on Earth . Its diameter is about 109 times that of Earth , and its mass is about 330,000 times that of Earth , accounting for about 99.86 % of the total mass of the Solar System . About three quarters of the Sun 's mass consists of hydrogen ( ~ 73 % ) ; the rest is mostly helium ( ~ 25 % ) , with much smaller quantities of heavier elements , including oxygen , carbon , neon , and iron . The Sun is a G-type main-sequence star ( G2V ) based on its spectral class . As such , it is informally referred to as a yellow dwarf . It formed approximately 4.6 billionAll numbers in this article are short scale . One billion is 109 , or 1,000,000,000 . years ago from the gravitational collapse of matter within a region of a large molecular cloud . Most of this matter gathered in the center , whereas the rest flattened into an orbiting disk that became the Solar System . The central mass became so hot and dense that it eventually initiated nuclear fusion in its core . It is thought that almost all stars form by this process . The Sun is roughly middle-aged ; it has not changed dramatically for more than four billion years , and will remain fairly stable for more than another five billion years . After hydrogen fusion in its core has diminished to the point at which it is no longer in hydrostatic equilibrium , the core of the Sun will experience a marked increase in density and temperature while its outer layers expand to eventually become a red giant . It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury and Venus , and render Earth uninhabitable . The enormous effect of the Sun on Earth has been recognized since prehistoric times , and the Sun has been regarded by some cultures as a deity . The synodic rotation of Earth and its orbit around the Sun are the basis of the solar calendar , which is the predominant calendar in use today .
2798
Global_dimming
While changes in cloud cover & aerosols lead to more sunlight hitting the surface, this can be compensated by the cooling effect on the atmosphere due to fewer clouds trapping less warmth and fewer absorbing aerosols absorbing less sunlight.
Global dimming Global dimming is the gradual reduction in the amount of global direct irradiance at the Earth 's surface that was observed for several decades after the start of systematic measurements in the 1950s . The effect varies by location , but worldwide it has been estimated to be of the order of a 4 % reduction over the three decades from 1960 -- 1990 . However , after discounting an anomaly caused by the eruption of Mount Pinatubo in 1991 , a very slight reversal in the overall trend has been observed . Global dimming is thought to have been caused by an increase in particulates such as sulfate aerosols in the atmosphere due to human action . It has interfered with the hydrological cycle by reducing evaporation and may have reduced rainfall in some areas . Global dimming also creates a cooling effect that may have partially counteracted the effect of greenhouse gases on global warming .
3074
Climate_sensitivity
Fourth Assessment Report (AR4), in which the likely range is given as 2.0°C to 4.5°C, with a best estimate of 3.0°C" (Pat Michaels)
Climate sensitivity Climate sensitivity is the equilibrium temperature change in response to changes of the radiative forcing . Therefore , climate sensitivity depends on the initial climate state , but potentially can be accurately inferred from precise palaeoclimate data . Slow climate feedbacks , especially changes of ice sheet size and atmospheric CO2 , amplify the total Earth system sensitivity by an amount that depends on the time scale considered . Although climate sensitivity is usually used in the context of radiative forcing by carbon dioxide ( CO2 ) , it is thought of as a general property of the climate system : the change in surface air temperature ( ΔTs ) following a unit change in radiative forcing ( RF ) , and thus is expressed in units of ° C / ( W/m2 ) . For this to be useful , the measure must be independent of the nature of the forcing ( e.g. from greenhouse gases or solar variation ) ; to first order this is indeed found to be so . The climate sensitivity specifically due to is often expressed as the temperature change in ° C associated with a doubling of the concentration of carbon dioxide in Earth 's atmosphere . For coupled atmosphere-ocean global climate models ( e.g. CMIP5 ) the climate sensitivity is an emergent property : it is not a model parameter , but rather a result of a combination of model physics and parameters . By contrast , simpler energy-balance models may have climate sensitivity as an explicit parameter . The terms represented in the equation relate radiative forcing ( RF ) to linear changes in global surface temperature change ( ΔTs ) via the climate sensitivity λ . It is also possible to estimate climate sensitivity from observations ; however , this is difficult due to uncertainties in the forcing and temperature histories .
1783
Attribution_of_recent_climate_change
Internal variability can only account for small amounts of warming and cooling over periods of decades, and scientific studies have consistently shown that it cannot account for the global warming over the past century.
Attribution of recent climate change Attribution of recent climate change is the effort to scientifically ascertain mechanisms responsible for recent climate changes on Earth , commonly known as ` global warming ' . The effort has focused on changes observed during the period of instrumental temperature record , when records are most reliable ; particularly in the last 50 years , when human activity has grown fastest and observations of the troposphere have become available . The dominant mechanisms are anthropogenic , i.e. , the result of human activity . They are : increasing atmospheric concentrations of greenhouse gases global changes to land surface , such as deforestation increasing atmospheric concentrations of aerosols . There are also natural mechanisms for variation including climate oscillations , changes in solar activity , and volcanic activity . According to the Intergovernmental Panel on Climate Change ( IPCC ) , it is `` extremely likely '' that human influence was the dominant cause of global warming between 1951 and 2010 . The IPCC defines `` extremely likely '' as indicating a probability of 95 to 100 % , based on an expert assessment of all the available evidence . Multiple lines of evidence support attribution of recent climate change to human activities : A basic physical understanding of the climate system : greenhouse gas concentrations have increased and their warming properties are well-established . Historical estimates of past climate changes suggest that the recent changes in global surface temperature are unusual . Computer-based climate models are unable to replicate the observed warming unless human greenhouse gas emissions are included . Natural forces alone ( such as solar and volcanic activity ) can not explain the observed warming . The IPCC 's attribution of recent global warming to human activities is a view shared by the scientific community , and is also supported by 196 other scientific organizations worldwide ( see also : scientific opinion on climate change ) .
2613
Greenhouse_gas
CO2 levels are measured by hundreds of stations scattered across 66 countries which all report the same rising trend.
Greenhouse gas A greenhouse gas ( abbrev . GHG ) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range . This process is the fundamental cause of the greenhouse effect . The primary greenhouse gases in Earth 's atmosphere are water vapor , carbon dioxide , methane , nitrous oxide , and ozone . Without greenhouse gases , the average temperature of Earth 's surface would be about -18 ° C , rather than the present average of 15 ° C . In the Solar System , the atmospheres of Venus , Mars and Titan also contain gases that cause a greenhouse effect . Human activities since the beginning of the Industrial Revolution ( taken as the year 1750 ) have produced a 40 % increase in the atmospheric concentration of carbon dioxide , from 280 ppm in 1750 to 406 ppm in early 2017 . This increase has occurred despite the uptake of a large portion of the emissions by various natural `` sinks '' involved in the carbon cycle . Anthropogenic carbon dioxide emissions ( i.e. , emissions produced by human activities ) come from combustion of fossil fuels , principally coal , oil , and natural gas , along with deforestation , soil erosion and animal agriculture . It has been estimated that if greenhouse gas emissions continue at the present rate , Earth 's surface temperature could exceed historical values as early as 2047 , with potentially harmful effects on ecosystems , biodiversity and the livelihoods of people worldwide . Recent estimates suggest that on the current emissions trajectory the Earth could pass a threshold of 2 ° C global warming , which the United Nations ' IPCC designated as the upper limit to avoid `` dangerous '' global warming , by 2036 .
1164
Disaster_risk_reduction
Hurricanes, tornadoes, floods, droughts and other natural disasters have yet to show any obvious long-term change."
Disaster risk reduction Disaster risk reduction ( DRR ) is a systematic approach to identifying , assessing and reducing the risks of disaster . It aims to reduce socio-economic vulnerabilities to disaster as well as dealing with the environmental and other hazards that trigger them . Here it has been strongly influenced by the mass of research on vulnerability that has appeared in print since the mid-1970s . It is the responsibility of development and relief agencies alike . It should be an integral part of the way such organizations do their work , not an add-on or one-off action . DRR is very wide-ranging : Its scope is much broader and deeper than conventional emergency management . There is potential for DRR initiatives in just about every sector of development and humanitarian work . The most commonly cited definition of DRR is one used by UN agencies such as UNISDR , also known as the UN Office for Disaster Risk Reduction , and UNDP : `` The conceptual framework of elements considered with the possibilities to minimize vulnerabilities and disaster risks throughout a society , to avoid ( prevention ) or to limit ( mitigation and preparedness ) the adverse impacts of hazards , within the broad context of sustainable development . ''
1154
Greenhouse_gas
[CO2] is also a greenhouse gas which helps maintain earth at a habitable temperature.
Greenhouse gas A greenhouse gas ( abbrev . GHG ) is a gas in an atmosphere that absorbs and emits radiation within the thermal infrared range . This process is the fundamental cause of the greenhouse effect . The primary greenhouse gases in Earth 's atmosphere are water vapor , carbon dioxide , methane , nitrous oxide , and ozone . Without greenhouse gases , the average temperature of Earth 's surface would be about -18 ° C , rather than the present average of 15 ° C . In the Solar System , the atmospheres of Venus , Mars and Titan also contain gases that cause a greenhouse effect . Human activities since the beginning of the Industrial Revolution ( taken as the year 1750 ) have produced a 40 % increase in the atmospheric concentration of carbon dioxide , from 280 ppm in 1750 to 406 ppm in early 2017 . This increase has occurred despite the uptake of a large portion of the emissions by various natural `` sinks '' involved in the carbon cycle . Anthropogenic carbon dioxide emissions ( i.e. , emissions produced by human activities ) come from combustion of fossil fuels , principally coal , oil , and natural gas , along with deforestation , soil erosion and animal agriculture . It has been estimated that if greenhouse gas emissions continue at the present rate , Earth 's surface temperature could exceed historical values as early as 2047 , with potentially harmful effects on ecosystems , biodiversity and the livelihoods of people worldwide . Recent estimates suggest that on the current emissions trajectory the Earth could pass a threshold of 2 ° C global warming , which the United Nations ' IPCC designated as the upper limit to avoid `` dangerous '' global warming , by 2036 .
2062
Global_warming
Global warming is increasing the magnitude and frequency of droughts and floods.
Global warming Global warming , also referred to as climate change , is the observed century-scale rise in the average temperature of the Earth 's climate system and its related effects . Multiple lines of scientific evidence show that the climate system is warming . Many of the observed changes since the 1950s are unprecedented in the instrumental temperature record which extends back to the mid 19th century , and in paleoclimate proxy records over thousands of years . In 2013 , the Intergovernmental Panel on Climate Change ( IPCC ) Fifth Assessment Report concluded that `` It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century . '' The largest human influence has been emission of greenhouse gases such as carbon dioxide , methane and nitrous oxide . Climate model projections summarized in the report indicated that during the 21st century the global surface temperature is likely to rise a further 0.3 to for their lowest emissions scenario and 2.6 to for the highest emissions scenario . These findings have been recognized by the national science academies of the major industrialized nations and are not disputed by any scientific body of national or international standing . Future climate change and associated impacts will differ from region to region around the globe . Anticipated effects include warming global temperature , rising sea levels , changing precipitation , and expansion of deserts in the subtropics . Warming is expected to be greater over land than over the oceans and greatest in the Arctic , with the continuing retreat of glaciers , permafrost and sea ice . Other likely changes include more frequent extreme weather events including heat waves , droughts , heavy rainfall with floods and heavy snowfall ; ocean acidification ; and species extinctions due to shifting temperature regimes . Effects significant to humans include the threat to food security from decreasing crop yields and the abandonment of populated areas due to rising sea levels . Because the climate system has a large `` inertia '' and greenhouse gases will stay in the atmosphere for a long time , many of these effects will not only exist for decades or centuries , but will persist for tens of thousands of years . Possible societal responses to global warming include mitigation by emissions reduction , adaptation to its effects , building systems resilient to its effects , and possible future climate engineering . Most countries are parties to the United Nations Framework Convention on Climate Change ( UNFCCC ) , whose ultimate objective is to prevent dangerous anthropogenic climate change . Parties to the UNFCCC have agreed that deep cuts in emissions are required and that global warming should be limited to well below 2.0 C-change relative to pre-industrial levels , with efforts made to limit warming to 1.5 C-change . Public reactions to global warming and concern about its effects are also increasing . A global 2015 Pew Research Center report showed a median of 54 % consider it `` a very serious problem '' . There are significant regional differences , with Americans and Chinese ( whose economies are responsible for the greatest annual CO2 emissions ) among the least concerned .
2869
Scientific_consensus_on_climate_change
Claims that the IPCC does not accurately represent the views and findings of the scientists, on whose work the IPCC reports are based, are not supported by the facts.
Scientific consensus on climate change There is currently a strong scientific consensus that the Earth is warming and that this warming is mainly caused by human activities. This consensus is supported by various studies of scientists' opinions and by position statements of scientific organizations, many of which explicitly agree with the Intergovernmental Panel on Climate Change (IPCC) synthesis reports. Nearly all actively publishing climate scientists (97–98%) support the consensus on anthropogenic climate change, and the remaining 2% of contrarian studies either cannot be replicated or contain errors.
1067
Taiga
"In an old climate, … extremely warm years were less common and snowpack was more reliable …
Taiga Taiga ( -LSB- ˈtaɪɡə -RSB- -LSB- тайга́ , p = tɐjˈɡa -RSB- from Turkic ) also known as boreal forest or snow forest , is a biome characterized by coniferous forests consisting mostly of pines , spruces and larches . The taiga is the world 's largest biome apart from the oceans . In North America it covers most of inland Canada and Alaska as well as parts of the extreme northern continental United States ( northern Minnesota through the Upper Peninsula of Michigan to Upstate New York and northern New England ) , where it is known as the Northwoods or `` North woods '' . In Eurasia , it covers most of Sweden , Finland , much of Norway , some of the Scottish Highlands , some lowland/coastal areas of Iceland , much of Russia from Karelia in the west to the Pacific Ocean ( including much of Siberia ) , and areas of northern Kazakhstan , northern Mongolia , and northern Japan ( on the island of Hokkaidō ) . However , the main tree species , the length of the growing season and summer temperatures vary . For example , the taiga of North America mostly consists of spruces ; Scandinavian and Finnish taiga consists of a mix of spruce , pines and birch ; Russian taiga has spruces , pines and larches depending on the region , while the Eastern Siberian taiga is a vast larch forest . A different use of the term taiga is often encountered in the English language , with `` boreal forest '' used in the United States and Canada to refer to only the more southerly part of the biome , while `` taiga '' is used to describe the more barren areas of the northernmost part of the biome approaching the tree line and the tundra biome . Hoffman ( 1958 ) discusses the origin of this differential use in North America and why it is an inappropriate differentiation of the Russian term . Although at high elevations taiga grades into alpine tundra through Krummholz , it is not exclusively an alpine biome ; and unlike subalpine forest , much of taiga is lowlands .
1256
Ice_age
'Next year or the year after, the Arctic will be free of ice'
Ice age An ice age is a period of long-term reduction in the temperature of Earth 's surface and atmosphere , resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers . Within a long-term ice age , individual pulses of cold climate are termed `` glacial periods '' ( or alternatively `` glacials '' or `` glaciations '' or colloquially as `` ice age '' ) , and intermittent warm periods are called `` interglacials '' . In the terminology of glaciology , ice age implies the presence of extensive ice sheets in both northern and southern hemispheres . By this definition , we are in an interglacial period -- the Holocene -- of the ice age . The ice age began 2.6 million years ago at the start of the Pleistocene epoch , because the Greenland , Arctic , and Antarctic ice sheets still exist .
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Global_catastrophic_risk
Their analysis calculates the existential climate-related security risk to Earth through a scenario set 30 years into the future.
Global catastrophic risk A global catastrophic risk is a hypothetical future event that has the potential to damage human well-being on a global scale . Some events could cripple or destroy modern civilization . Any event that could cause human extinction is known as an existential risk . Potential global catastrophic risks include anthropogenic risks ( technology risks , governance risks ) and natural or external risks . Examples of technology risks are hostile artificial intelligence , biotechnology risks , or nanotechnology weapons . Insufficient global governance creates risks in the social and political domain ( potentially leading to a global war with or without a nuclear holocaust , bioterrorism using genetically modified organisms , cyberterrorism destroying critical infrastructures like the electrical grid , or the failure to manage a natural pandemic ) as well as problems and risks in the domain of earth system governance ( with risks resulting from global warming , environmental degradation , mineral resource exhaustion , fossil energy exhaustion , or famine as a result of non-equitable resource distribution , human overpopulation , crop failures and non-sustainable agriculture ) . Examples for non-anthropogenic risks are an asteroid impact event , a supervolcanic eruption , a lethal gamma-ray burst , a geomagnetic storm destroying all electronic equipment , natural long-term climate change , or extraterrestrial life impacting life on Earth .
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Temperature_record_of_the_past_1000_years
For instance, in the original hockey stick (ending 1980) the last 30-40 years of data points slightly downwards.
Temperature record of the past 1000 years For information on the description of the Medieval Warm Period and Little Ice Age in various IPCC reports see MWP and LIA in IPCC reportsThe temperature record of the past 1,000 years is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 150 years at a global scale . Large-scale reconstructions covering part or all of the 1st millennium and 2nd millennium have shown that recent temperatures are exceptional : the Intergovernmental Panel on Climate Change Fourth Assessment Report of 2007 concluded that `` Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely '' the highest in at least the past 1,300 years . '' The curve shown in graphs of these reconstructions is widely known as the hockey stick graph because of the sharp increase in temperatures during the last century . As of 2010 this broad pattern was supported by more than two dozen reconstructions , using various statistical methods and combinations of proxy records , with variations in how flat the pre-20th-century `` shaft '' appears . Sparseness of proxy records results in considerable uncertainty for earlier periods . Individual proxy records , such as tree ring widths and densities used in dendroclimatology , are calibrated against the instrumental record for the period of overlap . Networks of such records are used to reconstruct past temperatures for regions : tree ring proxies have been used to reconstruct Northern Hemisphere extratropical temperatures ( within the tropics trees do not form rings ) but are confined to land areas and are scarce in the Southern Hemisphere which is largely ocean . Wider coverage is provided by multiproxy reconstructions , incorporating proxies such as lake sediments , ice cores and corals which are found in different regions , and using statistical methods to relate these sparser proxies to the greater numbers of tree ring records . The `` Composite Plus Scaling '' ( CPS ) method is widely used for large-scale multiproxy reconstructions of hemispheric or global average temperatures ; this is complemented by Climate Field Reconstruction ( CFR ) methods which show how climate patterns have developed over large spatial areas , making the reconstruction useful for investigating natural variability and long-term oscillations as well as for comparisons with patterns produced by climate models . During the 1,900 years before the 20th century , it is likely that the next warmest period was from 950 to 1100 , with peaks at different times in different regions . This has been called the Medieval Warm Period , and some evidence suggests widespread cooler conditions during a period around the 17th century known as the Little Ice Age . In the hockey stick controversy , contrarians have asserted that the Medieval Warm Period was warmer than at present , and have disputed the data and methods of climate reconstructions .
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Climate_sensitivity
Some global warming 'skeptics' argue that the Earth's climate sensitivity is so low that a doubling of atmospheric CO2 will result in a surface temperature change on the order of 1°C or less, and that therefore global warming is nothing to worry about.
Climate sensitivity Climate sensitivity is the equilibrium temperature change in response to changes of the radiative forcing . Therefore , climate sensitivity depends on the initial climate state , but potentially can be accurately inferred from precise palaeoclimate data . Slow climate feedbacks , especially changes of ice sheet size and atmospheric CO2 , amplify the total Earth system sensitivity by an amount that depends on the time scale considered . Although climate sensitivity is usually used in the context of radiative forcing by carbon dioxide ( CO2 ) , it is thought of as a general property of the climate system : the change in surface air temperature ( ΔTs ) following a unit change in radiative forcing ( RF ) , and thus is expressed in units of ° C / ( W/m2 ) . For this to be useful , the measure must be independent of the nature of the forcing ( e.g. from greenhouse gases or solar variation ) ; to first order this is indeed found to be so . The climate sensitivity specifically due to is often expressed as the temperature change in ° C associated with a doubling of the concentration of carbon dioxide in Earth 's atmosphere . For coupled atmosphere-ocean global climate models ( e.g. CMIP5 ) the climate sensitivity is an emergent property : it is not a model parameter , but rather a result of a combination of model physics and parameters . By contrast , simpler energy-balance models may have climate sensitivity as an explicit parameter . The terms represented in the equation relate radiative forcing ( RF ) to linear changes in global surface temperature change ( ΔTs ) via the climate sensitivity λ . It is also possible to estimate climate sensitivity from observations ; however , this is difficult due to uncertainties in the forcing and temperature histories .