query: By 2050 there’s a scientific consensus that we reached the tipping point for ice sheets in Greenland and the West Antarctic

positive: Sea level rise A sea level rise is an increase in the volume of water in the world 's oceans , resulting in an increase in global mean sea level . Sea level rise is usually attributed to global climate change by thermal expansion of the water in the oceans and by melting of Ice sheets and glaciers on land . Melting of floating ice shelves or icebergs at sea raises sea levels only slightly .   Sea level rise at specific locations may be more or less than the global average . Local factors might include tectonic effects , subsidence of the land , tides , currents , storms , etc. .  Sea level rise is expected to continue for centuries . Because of the slow inertia , long response time for parts of the climate system , it has been estimated that we are already committed to a sea-level rise of approximately 2.3 m for each degree Celsius of temperature rise within the next 2,000 years . IPCC Summary for Policymakers , AR5 , 2014 , indicated that the global mean sea level rise will continue during the 21st century , very likely at a faster rate than observed from 1971 to 2010 . Projected rates and amounts vary . A January 2017 NOAA report suggests a range of GMSL rise of 0.3 -- 2.5 m possible during the 21st century .   Sea level rises can considerably influence human populations in coastal and island regions and natural environments like marine ecosystems .

positive: 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.

negative: Greenland ice sheet The Greenland ice sheet ( Grønlands indlandsis , Sermersuaq ) is a vast body of ice covering 1710000 km ² , roughly 80 % of the surface of Greenland .   It is the second largest ice body in the world , after the Antarctic ice sheet . The ice sheet is almost 2400 km long in a north-south direction , and its greatest width is 1100 km at a latitude of 77 ° N , near its northern margin . The mean altitude of the ice is 2135 m . The thickness is generally more than 2 km and over 3 km at its thickest point . It is not the only ice mass of Greenland -- isolated glaciers and small ice caps cover between 76000 and around the periphery . If the entire 2850000 km3 of ice were to melt , it would lead to a global sea level rise of 7.2 m . The Greenland Ice Sheet is sometimes referred to under the term inland ice , or its Danish equivalent , indlandsis . It is also sometimes referred to as an ice cap .

negative: 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 .

negative: Antarctic ice sheet The Antarctic ice sheet is one of the two polar ice caps of the Earth . It covers about 98 % of the Antarctic continent and is the largest single mass of ice on Earth . It covers an area of almost 14 e6km2 and contains 26.5 e6km3 of ice . Approximately 61 percent of all fresh water on the Earth is held in the Antarctic ice sheet , an amount equivalent to about 58 m of sea-level rise . In East Antarctica , the ice sheet rests on a major land mass , but in West Antarctica the bed can extend to more than 2,500 m below sea level . Much of the land in this area would be seabed if the ice sheet were not there .   In contrast to the melting of the Arctic sea ice , sea ice around Antarctica was expanding . The reasons for this are not fully understood , but suggestions include the climatic effects on ocean and atmospheric circulation of the ozone hole , and/or cooler ocean surface temperatures as the warming deep waters melt the ice shelves .

negative: West Antarctic Ice Sheet The Western Antarctic Ice Sheet ( WAIS ) is the segment of the continental ice sheet that covers West ( or Lesser ) Antarctica , the portion of Antarctica on the side of the Transantarctic Mountains which lies in the Western Hemisphere . The WAIS is classified as a marine-based ice sheet , meaning that its bed lies well below sea level and its edges flow into floating ice shelves . The WAIS is bounded by the Ross Ice Shelf , the Ronne Ice Shelf , and outlet glaciers that drain into the Amundsen Sea .   It is estimated that the volume of the Antarctic ice sheet is about 25.4 million km3 ( 6.1 million cu mi ) , and the WAIS contains just under 10 % of this , or 2.2 million km3 ( 530,000 cu mi ) . The weight of the ice has caused the underlying rock to sink by between 0.5 and 1 kilometres ( 0.31 -- 0.62 mi ) in a process known as isostatic depression .   Under the force of its own weight , the ice sheet deforms and flows . The interior ice flows slowly over rough bedrock . In some circumstances , ice can flow faster in ice streams , separated by slow-flowing ice ridges . The inter-stream ridges are frozen to the bed while the bed beneath the ice streams consists of water-saturated sediments . Many of these sediments were deposited before the ice sheet occupied the region , when much of West Antarctica was covered by the ocean . The rapid ice-stream flow is a non-linear process still not fully understood ; streams can start and stop for unclear reasons .   When ice reaches the coast , it either calves or continues to flow outward onto the water . The result is a large , floating ice shelf affixed to the continent .

negative: West Greenland Current The West Greenland Current is a weak cold water current that flows to the north along the west coast of Greenland . The current results from the movement of water flowing around the southernmost point of Greenland caused by the East Greenland Current .   According to Lloyd et al. , 2007 , the WGC is a WARM current connected to a broader scale North Atlantic climate via the combined influences of Atlantic water from the Irminger Current ( IC ) and polar water from the East Greenland Current .   Paleoclimatology records derived from foraminifera abundance show that periodic influxes of warm subsurface temperatures and near-bottom temperatures occurred throughout the Late Holocene epoch , particularly during the Holocene climatic optimum . The increased flow from the nearby East Greenland Current was associated with increased glacial iceberg calving from the large Jakobshavn Isbrae glacial outlet within the western Greenland Ice Sheet , causing rapid melting and destabilization events . Following the Neoglaciation , the Jakobshavn outlet formed a floating ice tongue around 2000 years before present .

negative: West Antarctica West Antarctica , or Lesser Antarctica , one of the two major regions of Antarctica , is the part of that continent that lies within the Western Hemisphere , and includes the Antarctic Peninsula . It is separated from East Antarctica by the Transantarctic Mountains and is covered by the West Antarctic Ice Sheet . It lies between the Ross Sea ( partly covered by the Ross Ice Shelf ) , and the Weddell Sea ( largely covered by the Filchner-Ronne Ice Shelf ) . It may be considered a giant peninsula stretching from the South Pole towards the tip of South America .   West Antarctica is largely covered by the Antarctic ice sheet , but there have been signs that climate change is having some effect and that this ice sheet may have started to shrink slightly . The coasts of the Antarctic Peninsula are the only parts of West Antarctica that become ( in summer ) ice-free . These constitute the Marielandia Antarctic tundra and have the warmest climate in Antarctica . The rocks are clad in mosses and lichens that can cope with the intense cold of winter and the short growing-season .

negative: Ice-sheet model In climate modelling , Ice-sheet models use numerical methods to simulate the evolution , dynamics and thermodynamics of ice sheets , such as the Greenland ice sheet , the Antarctic ice sheet or the large ice sheets on the northern hemisphere during the last glacial period . They are used for a variety of purposes , from studies of the glaciation of Earth over glacial -- interglacial cycles in the past to projections of ice-sheet decay under future global warming conditions .

negative: Greenland Ice Sheet Project The Greenland Ice Sheet Project ( GISP ) was a decade-long project to drill ice cores in Greenland that involved scientists and funding agencies from Denmark , Switzerland and the United States . Besides the U.S. National Science Foundation ( NSF ) , funding was provided by the Swiss National Science Foundation and the Danish Commission for Scientific Research in Greenland . The ice cores provide a proxy archive of temperature and atmospheric constituents that help to understand past climate variations .   The preliminary GISP field work started in 1971 at Dye 3 , where a 372 meter deep , 10.2 cm diameter core was recovered . After this , annual field expeditions were carried out to drill intermediate depth cores at various locations on the ice sheet . The first was a 398 m core at Milcent and another was a 405 m core at the Crete station in 1974 . After working out various logistical and engineering problems related to the development of a more sophisticated drilling rig , drilling to bedrock at Dye 3 began in the summer of 1979 using a new Danish electro-mechanical ice drill . In the first year , an 18 cm diameter hole was drilled and cased to a depth of 80 m. Coring continued for two more seasons , and on August 10 , 1981 , bedrock was reached at a depth of 2037 m . The Dye 3 site was a compromise : glaciologically , a higher site on the ice divide with smooth bedrock would have been better ; logistically , such a site would have been too remote .

negative: East Greenland Ice-Core Project The East Greenland Ice-Core Project , known as EGRIP , is a scientific project that plans to retrieve an ice core from the Northeast Greenland ice stream . The first season in the field was 2015 ; the project is expected to be drilling through to the base of the ice sheet by 2020 .   Much of the camp set up for the North Greenland Eemian Ice Drilling Project ( NEEM ) was moved to the EGRIP location in 2015 . The equipment was towed by several tractors . The team ran low on fuel and had to abandon some equipment , arriving at the EGRIP location on 26 May , after nine days of towing .

negative: East Antarctic Ice Sheet The East Antarctic Ice Sheet ( EAIS ) is one of two large ice sheets in Antarctica , and the largest on the entire planet . The EAIS lies between 45 ° west and 168 ° east longitudinally .   The EAIS is considerably larger in area and mass than the West Antarctic Ice Sheet ( WAIS ) . It is separated from the WAIS by the Transantarctic Mountains . The EAIS rests upon a large land mass , contrary to that of the WAIS , which rests mainly on bedrock below sea level . The EAIS is also home to the thickest ice on the frozen white continent , at 15,700 ft ( 4,800 m ) . More well known , however , is that the EAIS is home to the geographic South Pole as well as of the Amundsen-Scott South Pole Station .

negative: Quaternary glaciation The Quaternary glaciation , also known as the Pleistocene glaciation or the current ice age , is a series of glacial events separated by interglacial events during the Quaternary period from 2.58 Ma ( million years ago ) to present . During this period , ice sheets expanded , notably from out of Antarctica and Greenland , and fluctuating ice sheets occurred elsewhere ( for example , the Laurentide ice sheet ) . The major effects of the ice age are erosion and deposition of material over large parts of the continents , modification of river systems , creation of millions of lakes , changes in sea level , development of pluvial lakes far from the ice margins , isostatic adjustment of the crust , and abnormal winds . It affected oceans , flooding , and biological communities . The ice sheets themselves , by raising the albedo , affect a major feedback on climate cooling .

negative: Tipping point Tipping point may refer to :

negative: 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 .

negative: Last Glacial Maximum The Last Glacial Maximum ( LGM ) was the last period in the Earth 's climate history during the last glacial period when ice sheets were at their greatest extension . Growth of the ice sheets reached their maximum positions in about 24,500 BCE . Deglaciation commenced in the Northern Hemisphere between approximately 18,000 to 17,000 BCE and in Antarctica approximately 12,500 BCE , which is consistent with evidence that it was the primary source for an abrupt rise in the sea level in about 12,500 BCE .   Vast ice sheets covered much of North America , northern Europe , and Asia . The ice sheets profoundly affected Earth 's climate by causing drought , desertification , and a dramatic drop in sea levels . It was followed by the Late Glacial .

negative: Giesecke Glacier Giesecke Glacier ( Giesecke brær ) is a glacier in the Qaasuitsup municipality in northwestern Greenland . Its outflow is split in the center by a nunatak . Through two tongues it drains the Greenland ice sheet westwards into Kangerlussuaq Icefjord . The northern tongue ( Qeqertarsuup Sermia ) reaches the fjord at . The southern tongue ( Kakiffait Sermiat ) reaches the fjord at .

negative: Robert Bindschadler Dr. Robert Bindschadler is a senior fellow at NASA 's Goddard Space Flight Center and has been an active field researcher in the Antarctic for over 25 years . He is a past president of the International Glaciological Society , chairs the West Antarctic Ice Sheet Initiative , is an editor for the Journal of Glaciology and has led 14 expeditions to Antarctica and has participated in numerous other expeditions around the world including Greenland . He has also testified before Congress and has briefed the U.S. vice president concerning ice-sheet stability and is often quoted or featured in the media . He was born in Pittsburgh and received a B.S. in astronomy and physics in 1971 from the University of Michigan and earned his Ph.D in Geophysics from the University of Washington in 1978 and did post doctoral work in Switzerland prior to working at NASA .   His work revolves around the dynamics of glaciers and ice sheets using remote sensing technology . He has developed applications used to measure ice velocity and elevation using radar imagery which monitors the melting of ice sheets and detects changes in the volume of ice-sheets using radar altimetry . He has received numerous awards including Exceptional scientific achievement by NASA in 1994 as well as the Goddard Senior fellow in 2000 .

negative: Antarctic Peninsula The Antarctic Peninsula is the northernmost part of the mainland of Antarctica , located at the base of the Southern Hemisphere . At the surface , it is the biggest , most prominent peninsula in Antarctica as it extends 1300 km from a line between Cape Adams ( Weddell Sea ) and a point on the mainland south of Eklund Islands . Beneath the ice sheet which covers it , the Antarctic Peninsula consists of a string of bedrock islands ; these are separated by deep channels whose bottoms lie at depths considerably below current sea level . They are joined together by a grounded ice sheet . Tierra del Fuego , the southernmost tip of South America , lies only about 1000 km away across the Drake Passage .   The Antarctic Peninsula is currently dotted with numerous research stations and nations have made multiple claims of sovereignty . The peninsula is part of disputed and overlapping claims by Argentina , Chile and the United Kingdom . None of these claims has international recognition and , under the Antarctic Treaty System , the respective countries do not attempt to enforce their claims . Argentina has the most bases and personnel stationed on the peninsula .

negative: Climate inertia Climate inertia describes the widespread inherent characteristic of the climate , ecological , and socio-economic systems . Inertia from anthropogenic impacts may be slow to become apparent , or could be irreversible if climate change crosses associated thresholds . Melting ice sheets in Greenland and Antarctica take time to respond to the emissions of fossil fuel carbon in the climate system . The global warming also causes thermal inertia , thermal expansion of the oceans , which contributes to sea level rise . It has been estimated that we are already committed to a sea-level rise of approximately 2.3 meters for each degree of temperature rise within the next 2,000 years .

negative: Greenland ice core project The Greenland Ice Core Project ( GRIP ) was a multinational European research project , organized through the European Science Foundation . Funding came from 8 nations ( Belgium , Denmark , France , Germany , Iceland , Italy , Switzerland , and United Kingdom ) , and from the European Union .   The project ran from 1989 to 1995 , with drilling seasons from 1990 to 1992 . GRIP successfully drilled a 3029-metre ice core to the bed of the Greenland ice sheet at Summit , Central Greenland from 1989 to 1992 at .   Studies of isotopes and various atmospheric constituents in the core have revealed a detailed record of climatic variations reaching more than 100,000 years back in time . The results indicate that Holocene climate has been remarkably stable and have confirmed the occurrence of rapid climatic variation during the last ice age ( the Wisconsin ) . Delta-O-18 variations observed in the core part believed to date from the Eemian Stage have not been confirmed by other records including the NGRIP core and are now believed not to represent climate events : the interglacial climate of Eemian Stage appears to have been as stable as the Holocene .

negative: Echelmeyer Ice Stream The Echelmeyer Ice Stream , formerly known as Ice Stream F , is a glaciological feature of the West Antarctic Ice Sheet . It is an ice stream flowing west to the Shirase Coast to the north of the MacAyeal Ice Stream , and is one of several major ice streams draining from Marie Byrd Land into the Ross Ice Shelf . The ice streams were investigated and mapped by U.S. Antarctic Research Program personnel in a number of field seasons from 1983 -- 84 and originally named Ice Stream A , B , C , etc. , according to their position from south to north .   The name was changed from Ice Stream F by the Advisory Committee on Antarctic Names in 2002 to honor Dr. Keith A. Echelmeyer of the Geophysical Institute , University of Alaska , Fairbanks , who studied the flow of Marie Byrd Land ice streams , 1992 -- 93 and 1994 -- 95 , as well as the fast flow of surging glaciers in Alaska and Greenland . Dr. Echelmeyer was a student of Barclay Kamb for whom Kamb Ice Stream is named .

negative: Isunngua Isunngua ( old spelling : Isúngua ) is a highland in the Qeqqata municipality in central-western Greenland , located immediately west of the Greenland Ice Sheet edge . In large part it is covered by the tundra , although in the immediate vicinity of the Sermersuaq ice sheet it gradually becomes exposed , barren , and largely devoid of life . The climate is polar continental , with the area receiving very little rainfall . Isunngua is a calving site for reindeer .

negative: Whillans Ice Stream Whillans Ice Stream is a glaciological feature of the West Antarctic Ice Sheet , formerly known as Ice Stream B , renamed in 2001 in honor of Ohio State University glaciologist Ian Whillans .

negative: List of Antarctic ice shelves This is a list of Antarctic ice shelves .   Ice shelves are attached to 44 % of the Antarctic coastline . Their total area is 1,541,700 km ² . Names are also listed in the Scientific Committee on Antarctic Research , Gazetteer . The ice shelf areas are listed below , clockwise , starting in the west of East Antarctica :   † Indicates that the ice shelf has collapsed .

negative: Kamb Ice Stream Kamb Ice Stream , a glaciological feature of the West Antarctic Ice Sheet , formerly known as Ice Stream C , renamed in 2001 in honor of Caltech Glaciologist Dr. Barclay Kamb .

negative: ICESat ICESat ( Ice , Cloud , and land Elevation Satellite ) , part of NASA 's Earth Observing System , was a satellite mission for measuring ice sheet mass balance , cloud and aerosol heights , as well as land topography and vegetation characteristics . ICESat was launched 13 January 2003 on a Delta II rocket from Vandenberg Air Force Base in California into a near-circular , near-polar orbit with an altitude of approximately 600 km . It operated for seven years before being retired in February 2010 , after its scientific payload shut down and scientists were unable to restart it .   The ICESat mission was designed to provide elevation data needed to determine ice sheet mass balance as well as cloud property information , especially for stratospheric clouds common over polar areas . It provides topography and vegetation data around the globe , in addition to the polar-specific coverage over the Greenland and Antarctic ice sheets . The satellite was found useful in assessing important forest characteristics , including tree density .

negative: 2050s The 2050s is a decade of the Gregorian calendar that will begin on January 1 , 2050 and will end on December 31 , 2059 .

negative: Bindschadler Glacier Bindschadler Glacier is a glacier in the northwest part of Royal Society Range , Victoria Land , flowing north between Table Mountain and Platform Spur to join Emmanuel Glacier . It was named by the Advisory Committee on Antarctic Names in 1992 after glaciologist Robert A. Bindschadler of the NASA Goddard Space Flight Center ; from 1983 a principal investigator for United States Antarctic Research Program studies of the West Antarctic Ice Sheet including dynamics of ice streams in the Siple Coast area , their interaction with the Ross Ice Shelf , and the role of polar ice sheets in global climate change .

negative: King Frederick VI Coast Not to be confused with King Frederick VIII Land   King Frederick VI Coast ( Kong Frederik VI Kyst ) is a major geographic division of Greenland . It comprises the coastal area of Southeastern Greenland in Sermersooq and Kujalleq municipalities fronting the Irminger Sea of the North Atlantic Ocean . It is bordered by King Christian IX Land on the north and the Greenland Ice Sheet to the west .   The King Frederick VI Coast stretches for about 590 km and is characterized by a succession of short fjords , steep mountains and small coastal islands . There is a narrow belt of ice-free land between the shore and the Inland ice cap , interrupted by active glaciers reaching the shore with the ice limit varying seasonally from year to year . Owing to the movement of pack ice in the area and frequent gale-force winds that sweep down from the Greenland ice cap , it is often difficult to approach or navigate along the coast by ship .

negative: Petermann Glacier Petermann Glacier is a large glacier located in North-West Greenland to the east of Nares Strait . It connects the Greenland ice sheet to the Arctic Ocean near 81 degrees north latitude . It is named after the German cartographer August Heinrich Petermann


query: “Our analyses do not indicate  acceleration in sea level in U.S. tide gauge records during the 20th  century,” the study’s authors concluded.

positive: Sea level rise A sea level rise is an increase in the volume of water in the world 's oceans , resulting in an increase in global mean sea level . Sea level rise is usually attributed to global climate change by thermal expansion of the water in the oceans and by melting of Ice sheets and glaciers on land . Melting of floating ice shelves or icebergs at sea raises sea levels only slightly .   Sea level rise at specific locations may be more or less than the global average . Local factors might include tectonic effects , subsidence of the land , tides , currents , storms , etc. .  Sea level rise is expected to continue for centuries . Because of the slow inertia , long response time for parts of the climate system , it has been estimated that we are already committed to a sea-level rise of approximately 2.3 m for each degree Celsius of temperature rise within the next 2,000 years . IPCC Summary for Policymakers , AR5 , 2014 , indicated that the global mean sea level rise will continue during the 21st century , very likely at a faster rate than observed from 1971 to 2010 . Projected rates and amounts vary . A January 2017 NOAA report suggests a range of GMSL rise of 0.3 -- 2.5 m possible during the 21st century .   Sea level rises can considerably influence human populations in coastal and island regions and natural environments like marine ecosystems .

positive: Past sea level Global or eustatic sea level has fluctuated significantly over the Earth 's history . The main factors affecting sea level are the amount and volume of available water and the shape and volume of the ocean basins . The primary influences on water volume are the temperature of the seawater , which affects density , and the amounts of water retained in other reservoirs like rivers , aquifers , lakes , glaciers , polar ice caps and sea ice . Over geological timescales , changes in the shape of the oceanic basins and in land/sea distribution affect sea level . In addition to eustatic changes , local changes in sea level are caused by tectonic uplift and subsidence .   Over geologic time sea level has fluctuated by hundreds of meters . Today 's interglacial level is near historic highs and is 130 meters above the low level reached during the Last Glacial Maximum 19,000 -- 20,000 years ago .   Observational and modeling studies of mass loss from glaciers and ice caps indicate a contribution to sea-level rise of 0.2 to 0.4 mm/yr averaged over the 20th century . Over this last million years , whereas it was higher most of the time before then , sea level was lower than today .

negative: S scale S scale ( or S gauge ) is a model railroad scale modeled at 1:64 scale , S scale track gauge ( space between the rails ) is . S gauge trains are manufactured in both DC and AC powered varieties . S gauge is not to be confused with toy train standard gauge , a large-scale standard for toy trains in the early part of the 20th century .

negative: Staff (head) gauge A staff ( head ) gauge is calibrated scale which is used to provide a visual indication of liquid level . When used on an inclined or sloped surface , a staff gauge is usually calibrated so that the indicated level is the true vertical level .   Staff gauges are commonly installed at stream gauging stations to indicate the water stage . They are also used to indicate the water level ( and hence flow rate ) in open channel primary devices ( flumes or weirs ) .   Category : Water supply

negative: Victorian Railways narrow-gauge guard's vans The Victorian Railways narrow-gauge guard 's vans were operated on the narrow-gauge lines of Victorian Railways from the late 19th century to the early 20th century .

negative: Storm tides of the North Sea A storm tide is a tide with a high flood period caused by a storm . Storm tides can be a severe danger to the coast and the people living along the coast . The water level can rise to more than 5 metres ( 17 ft ) above the normal tide .   The North Sea , especially the Netherlands , northern Germany and Denmark is particularly susceptible to storm tides . The coastline of the German Bight forms an L-shape facing northwest . Also vulnerable is the southern North Sea between England and the Netherlands , where the sea shallows and is funnelled between the land . For the protection of the low-lying areas along the coast , long and high dike systems have been built . Storm tides are a regular occurrence in these areas ; usually , there are several storm tides each winter . Most of them do not cause significant damage .

negative: Our Southern Highlanders Our Southern Highlanders : A Narrative of Adventure in the Southern Appalachians and a Study of Life Among the Mountaineers is a book written by American author Horace Kephart ( 1862 -- 1931 ) , first published in 1913 and revised in 1922 . Inspired by the years Kephart spent among the inhabitants of the remote Hazel Creek region of the Great Smoky Mountains , the book provides one of the earliest realistic portrayals of life in the rural Appalachian Mountains and one of the first serious analyses of Appalachian culture . While modern historians and writers have criticized Our Southern Highlanders for focusing too much on sensationalistic aspects of mountain culture , the book was an important departure from the previous century 's local color writings and their negative distortions of mountain people .

negative: Bill Williams (trader) Bill M. Williams ( born 1932 ) is an American trader and author of books on trading psychology , technical analysis and chaos theory in trading the stock , commodity , and foreign exchange ( Forex ) markets . His study of stock market data led him to develop a number of technical analyses that identify trends in the financial markets . Indicators like Accelerator/Decelerator Oscillator , Alligator , Awesome Oscillator , Fractals , Gator Oscillator , and Market Facilitation Index are popular today in Forex , stock and other financial markets .

negative: Pacific Division (United States Army) Pacific Division of the U. S. Army was one of its superior administrative organizations that existed during the early 19th century and for a short time in the early 20th century .

negative: General levelling of France The General Levelling of France ( nivellement général de la France or NGF )  forms a network of benchmarks in mainland France and Corsica , now overseen by the Institut Géographique National . It is now the official levelling network in mainland France . It is made up of two networks :  NGF - IGN69 for mainland France , with the ` zero level ' determined by the tide gauge at Marseille  NGF - IGN78 for Corsica , with the ` zero level ' determined by the tide gauge at Ajaccio   Category : Topography  Category : Geography of France

negative: Pļaviņas–Gulbene Railway The Pļaviņas -- Gulbene Railway is a 98 km long , gauge railway built in the 20th century to connect Pļaviņas and Valka . The railway was originally part of a narrow gauge railway , but was converted to the current gauge during World War I.

negative: Conoclinium coelestinum Conoclinium coelestinum , the blue mistflower , is a North American species of herbaceous perennial flowering plant in the sunflower family . It was formerly classified in the genus Eupatorium , but phylogenetic analyses in the late 20th century research indicated that that genus should be split , and the species was reclassified in Conoclinium .

negative: S.J. Goldsmith Samuel Joseph ( Shmuel/Sam ) Goldsmith ( 1910 -- 1995 ) was a journalist , author , and editor in the Jewish and English press , whose reports and analyses are valuable sources for the understanding of key events in twentieth-century Europe and the Middle East and who shaped opinion among and about Jews during the second half of the 20th century .

negative: Four Centuries of Modern Iraq Four Centuries of Modern Iraq is a historic book authored by Stephen Hemsley Longrigg published first time in United kingdom on 1925 . It covers events in Iraq between early 16th century to early 20th century when Iraq was a neglected part of the Ottoman Empire . Few books have been written about Iraq in that period . The author uses oriental sources , the books of Iraqi historians and the experience of his long residence in Iraq to discuss the country 's turbulent history . The author concludes that Iraq had made little progress during last four centuries and it was still lack of ability and resources to be independent and self-government .

negative: Tidal flooding Tidal flooding , also known as sunny day flooding or nuisance flooding , is the temporary inundation of low-lying areas , especially streets , during exceptionally high tide events , such as at full and new moons . The highest tides of the year may be known as the king tide , with the month varying by location . In Florida , controversy was created when state-level government mandated that the term `` nuisance flooding '' and other terms be used in place of terms such as sea level rise , climate change and global warming , prompting allegations of climate change denial , specifically against Governor Rick Scott . This amid Florida , specifically South Florida and the Miami metropolitan area being one of the most at risk area in the world for the potential effects of sea level rise , and where the frequency and severity of tidal flooding events increased in the 21st century . The issue is more bipartisan in South Florida , particularly in places like Miami Beach , where a several hundred million dollar project is underway to install more than 50 pumps and physically raise roads to combat the flooding , mainly along the west side of South Beach , formerly a mangrove wetland where the average elevation is less than one meter ( 3.3 feet ) . In the Miami area , where the vast majority of the land is below 10 ft , even a one-foot increase over the average high tide can cause widespread flooding . The 2015 and 2016 king tide event levels reached about 4 ft MLLW , 3 ft above mean sea level , or about 2 ft NAVD88 , and nearly the same above MHHW . While the tide range is very small in Miami , averaging about 2 ft , with the greatest range being less than 2 m , the area is very acute to minute differences down to single inches due to the vast area low elevation . NOAA tide gauge data for most stations shows current water level graphs relative to a fixed datum , as well as mean sea level trends for some stations . During the king tides , the local Miami area tide gauge at Virginia Key shows levels running at times 1 ft or more over datum .   Fort Lauderdale has installed over one hundred tidal valves since 2013 to combat flooding . Fort Lauderdale is nicknamed the `` Venice of America '' due to its roughly 165 mi of canals .   Tidal flooding is capable of majorly inhibiting natural gravity-based drainage systems in low-lying areas when it reaches levels that are below visible inundation of the surface , but which are high enough to incapacitate the lower drainage or sewer system . Thus , even normal rainfall or storm surge events can cause greatly amplified flooding effects . One passive solution to intrusion through drainage systems are one way back-flow valves in drainage ways . However , while this may prevent a majority of the tidal intrusion , it also inhibits drainage during exceptionally high tides that shut the valves . In Miami Beach , where resilience work is underway , the pump systems replace insufficient gravity-based systems .

negative: Rossby whistle The Rossby whistle is the oscillation of sea-level and bottom pressure in the Caribbean Sea with the period of 120 days and influenced by propagating westward oceanic Rossby wave .   It is observed that a baroclinic Rossby wave propagating westward across the Caribbean Sea , oscillating with a period of 120 days , is rapidly returned to the east along the southern boundary as coastal shelf waves . The porous boundary of the Caribbean Sea results in this oscillation influencing a mass exchange with the wider ocean , leading to an almost uniform bottom pressure variability over the Grenada , Venezuela , and Colombia basins . These observations are based on satellite observation of the sea-level , monthly means of basin-averaged ocean bottom pressure using GRACE data , tide gauge measurements , and data from a bottom pressure recorder . The oscillation was first found in a numerical modelling simulation , from which is shown one cycle of the least squares fit of ( left ) sea level and ( right ) bottom pressure on basin averaged bottom pressure in the Caribbean Sea .

negative: Coastal management Coastal management is defense against flooding and erosion , and techniques that stop erosion to claim lands .   Coastal zones occupy less than 15 % of the Earth 's land area , while they host more than 40 % of the world population . Nearly 1.2 billion people live within 100 km of a shoreline and 100 m of sea level , with an average density nearly 3 times higher than the global average for population . With three-quarters of the world population expected to reside in the coastal zone by 2025 , human activities originating from this small land area will impose heavy pressure on coasts . Coastal zones contain rich resources to produce goods and services and are home to most commercial and industrial activities .   In the European Union , almost half of the population lives within 50 kilometres of the sea and coastal resources produce much of the Union 's economic wealth . The fishing , shipping and tourism industries all compete for space along Europe 's estimated 89,000 km of coastline and coastal zones contain some of Europe 's most fragile and valuable natural habitats .   Protection against sea level rise in the 21st century will be especially important , as sea level rise accelerates . Changes in sea level damage beaches and coastal systems . Coastal sediments are disturbed and suspended by wave and tide energy .

negative: Tsunami warning system A tsunami warning system ( TWS ) is used to detect tsunamis in advance and issue warnings to prevent loss of life and damage . It is made up of two equally important components : a network of sensors to detect tsunamis and a communications infrastructure to issue timely alarms to permit evacuation of the coastal areas . There are two distinct types of tsunami warning systems : international and regional . When operating , seismic alerts are used to instigate the watches and warnings ; then , data from observed sea level height ( either shore-based tide gauges or DART buoys ) are used to verify the existence of a tsunami . Other systems have been proposed to augment the warning procedures ; for example , it has been suggested that the duration and frequency content of t-wave energy ( which is earthquake energy trapped in the ocean SOFAR channel ) is indicative of an earthquake 's tsunami potential .

negative: Operation Sea Lion in fiction There is a large body of fiction set in an alternate history or a secret history , where the Operation Sea Lion , a German plan of invasion of Britain during World War II , is attempted or successfully carried out . However , analyses by experts in 1974 concluded that there was little chance of the plan succeeding .

negative: Hardangerjøkulen Hardangerjøkulen is the sixth largest glacier in mainland Norway . It is located in the municipalities of Eidfjord and Ulvik in Hordaland county . It is located about 16 km northeast of the village of Eidfjord , about 5 km south of Finse , and about 20 km west of Haugastøl .   Hardangerjøkulen 's highest point is 1,863 m above sea level , and is the highest point in Hordaland county . Its lowest point is 1,050 m above sea level . The thickest measurement of the glacier was 380 m thick , but it has been getting thinner during the 20th century .

negative: Malek Alloula Malek Alloula ( 1937-2015 ) was an Algierian poet , writer , editor , and literary critic .   He is chiefly notable for his poetry and essays on philosophy . He wrote several books , notably a French publication entitled Le Harem Colonial , translated into English as The Colonial Harem , which was generally well received . The author analyses colonial photographic postcards of Algerian women from the late 19th and early 20th centuries , arguing that the postcards do not accurately represent Algerian women , but rather a Frenchman 's fantasy of the `` Oriental '' female .

negative: Ŭ Ŭ or ŭ is a letter in the Esperanto alphabet , based on u . It is also used in the Belarusian language , when written in the 20th-century form of the Belarusian Latin alphabet . The accent mark ( diacritic ) is known as a breve .   This letter should not be confused with u-caron , which is used to indicate u in the third tone of Chinese language pinyin ; Compare ( caron ) with ( breve ) .

negative: OPAL experiment OPAL was one of the major experiments at CERN 's LEP . OPAL studied particles and their interactions by collecting and analysing electron-positron collision events at LEP , the Large Electron-Positron collider . LEP was the largest particle accelerator in the world . There three other experiments at LEP were : ALEPH , DELPHI and L3 .

negative: Religiosity and education The relationship between the level of religiosity and the level of education has been studied since the second half of the 20th century .   The parameters of the two components diverse : the `` level of religiosity '' remains a concept which is difficult to differentiate scientifically , while the `` level of education '' is easier to compile , such as official data on this topic , because data on education is publicly accessible in many countries .   Different studies show contrasted conclusions regarding any link between the two concepts , depending on whether `` religiosity '' is measured by religious practices ( attendance at places of worship , for example ) or specific religious beliefs ( belief in miracles , for example ) , with notable differences between nations . For example , an international study states that in some Western nations the intensity of beliefs decreases with education , but attendance and religious practice increases . Other studies indicate that the religious have higher education than the non-religious . Other studies find that the positive correlation with low or non religiosity and education has been reversed in the past few decades .   In terms of university professors , one study concluded that in the US , the majority of professors , even at `` elite '' universities , were religious .

negative: Sea Wall, Guyana The Sea Wall is a 280-mile seawall that runs along much of Guyana 's coastline , and all of the coastline in the capital city of Georgetown . It protects settlements in the coastal areas of Guyana , most of which are below sea level at high tide .

negative: Culture of Washington, D.C. The culture of Washington , D.C. is influenced by the presence of the federal government , which has been instrumental in developing numerous cultural institutions throughout the city . During the early 20th century , Washington 's U Street Corridor was an important center for African American culture .

negative: Sea song Sea song or sea-song may refer to :  a sea song is a sailor 's song -- when expressly working songs , they are often sea shanties ( a shipboard song-type which flourished in the Age of Sail 's 19th century to the 20th century 's first half ) . -- As OED defined .

negative: Narrow-gauge lines of the Victorian Railways The former Victorian Railways , the state railway authority in Victoria , Australia , built a number of experimental narrow-gauge lines around the beginning of the 20th century . Although all were closed by the early 1960s , parts of two have been reopened as heritage railways .

negative: Coast to Kosciuszko Coast to Kosciuszko ( C2K ) is a 240 km ultramarathon race run each December in New South Wales , Australia . The race commences at Twofold Bay ( at sea level ) and concludes at Charlotte Pass ( 1837 m above sea level ) after reaching the summit of Mount Kosciuszko ( Australia 's highest point at 2228 m above sea level ) .

negative: Acceleration due to gravity Acceleration due to gravity may refer to  Gravitational acceleration , the acceleration caused by the gravitational attraction of massive bodies in general  Gravity of Earth , the acceleration caused by the gravitational attraction of the Earth  Standard gravity , or g , the standard value of gravitational acceleration at sea level on Earth

negative: St. Pauli Piers The St. Pauli Piers ( St. Pauli Landungsbrücken , often only referred to as Landungsbrücken ; -LSB- ˈlandʊŋsˌbʀʏkn̩ -RSB- ) , are the largest landing place in the Port of Hamburg , Germany , and also one of Hamburg 's major tourist attractions . Other English language translations include St. Pauli Landing Stages or St. Pauli Landing Bridges .   The piers are located in the St. Pauli area of Hamburg , between the lower harbour and the Fischmarkt ( Fish Market ) , on the banks of the Elbe river . The Landungsbrücken today form a central transportation hub , with S-Bahn , U-Bahn and ferry stations , and are also a major tourist magnet with numerous restaurants and departure points for harbour pleasure boats . There is an entrance to the Old Elbe tunnel at the western end of the Landungsbrücken . The eastern end of the building complex is marked by the Pegelturm ( water level tower ) . Halfway up the tower , there is a water level indicator built into the wall , which indicates the current stage of the tides .

negative: Legacy: A Journal of American Women Writers Legacy , A Journal of American Women Writers , is the only scholarly journal to focus specifically on American women 's writings from the 17th through the mid-20th century .   Each issue 's articles cover a wide range of topics : examinations of the works of individual authors ; genre studies ; analyses of race , ethnicity , gender , class , and sexualities in women 's literature ; and historical and material cultural issues pertinent to women 's lives and literary works .  In addition , Legacy regularly publishes profiles of lesser-known or newly recovered authors , reprints of primary works in all genres , and book reviews covering current scholarship in the field .   Legacy is published twice a year by the University of Nebraska Press and is available online through Project MUSE or through university electronic journal websites .

negative: Susan Gubar Susan D. Gubar ( born November 30 , 1944 ) is an American author and distinguished Professor Emerita of English and Women 's Studies at Indiana University . She is best known for co-authoring , with Sandra M. Gilbert , a standard feminist text , The Madwoman in the Attic : The Woman Writer and the Nineteenth-Century Literary Imagination ( 1979 ) and a trilogy on women 's writing in the 20th century .

negative: Sernada do Vouga Sernada do Vouga is a small Portuguese village in the parish of Macinhata do Vouga , in Águeda Municipality in Aveiro District .   Placed a few meters , downstream , of the estuary of Caima River and is bathed by Vouga River . Since the beginning of the 20th century , a centre for railroad activity , through the construction of Linha do Vale do Vouga and its location at the junction of the three ` legs ' of the route , i.e. Espinho , Aveiro and Viseu . With the closure , in January 1990 , of the link Sernada - Viseu , it lost part of its role but it retains the EMEF workshop for the Vouga line 's rolling stock . The Vouga Line is now Portugal 's only active narrow-gauge railway and is under threat of closure .