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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 holds enough ice to raise global sea levels by and is considerably larger in area and mass than the
West Antarctic Ice Sheet The Western Antarctic Ice Sheet (WAIS) is the segment of the continental ice sheet that covers West Antarctica, the portion of Antarctica on the side of the Transantarctic Mountains that lies in the Western Hemisphere. The WAIS is classified as ...
(WAIS). It is separated from the WAIS by the Transantarctic Mountains. The EAIS is the driest, windiest, and coldest place on Earth, with temperatures reported down to nearly -100°C. The EAIS holds the thickest ice on Earth, at . It is home to the geographic
South Pole The South Pole, also known as the Geographic South Pole, Terrestrial South Pole or 90th Parallel South, is one of the two points where Earth's axis of rotation intersects its surface. It is the southernmost point on Earth and lies antipod ...
and the
Amundsen–Scott South Pole Station The Amundsen–Scott South Pole Station is the United States scientific research station at the South Pole of the Earth. It is the southernmost point under the jurisdiction (not sovereignty) of the United States. The station is located on the ...
.


Temperature changes

Cooling in East Antarctica during the decades of the 1980s and 1990s partially offset the impact of
climate change In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...
on the West Antarctic Ice Sheet, which has warmed by more than 0.1 °C/decade in the last 50 years. The continent-wide average surface temperature trend of Antarctica is positive and
statistically significant In statistical hypothesis testing, a result has statistical significance when it is very unlikely to have occurred given the null hypothesis (simply by chance alone). More precisely, a study's defined significance level, denoted by \alpha, is the p ...
at >0.05 °C/decade since 1957.


Ice mass changes

An early analysis of
GRACE Grace may refer to: Places United States * Grace, Idaho, a city * Grace (CTA station), Chicago Transit Authority's Howard Line, Illinois * Little Goose Creek (Kentucky), location of Grace post office * Grace, Carroll County, Missouri, an uninc ...
-based studies data indicated that the EAIS was losing mass at a rate of 57 billion tonnes per year and that the ''total'' Antarctic ice sheet (including WAIS, and EAIS coastal areas) was losing mass at a rate of 152 cubic kilometers (c. 139 billion tonnes) per year. A more recent estimate published in November 2012 and based on the GRACE data as well as on an improved glacial isostatic adjustment model indicates that East Antarctica actually gained mass from 2002 to 2010 at a rate of . Because it is currently gaining mass, East Antarctic Ice Sheet is not expected to play a role in the
21st century The 21st (twenty-first) century is the current century in the ''Anno Domini'' era or Common Era, under the Gregorian calendar. It began on 1 January 2001 ( MMI) and will end on 31 December 2100 ( MMC). Marking the beginning of the 21st centur ...
sea level rise Globally, sea levels are rising due to human-caused climate change. Between 1901 and 2018, the globally averaged sea level rose by , or 1–2 mm per year on average.IPCC, 2019Summary for Policymakers InIPCC Special Report on the Ocean and Cr ...
. However, it would play an increasingly larger role after 2100 if global warming were to reach higher levels. The 2019
IPCC The Intergovernmental Panel on Climate Change (IPCC) is an intergovernmental body of the United Nations. Its job is to advance scientific knowledge about climate change caused by human activities. The World Meteorological Organization (WMO) ...
SROCC used the findings of three studies to estimate the potential sea level rise by the year 2300: it suggested that under the Representative Concentration Pathway 8.5, which is associated with continually increasing anthropogenic emissions, sea level rise from Antarctica alone would amount to a
median In statistics and probability theory, the median is the value separating the higher half from the lower half of a data sample, a population, or a probability distribution. For a data set, it may be thought of as "the middle" value. The basic f ...
of 1.46 metres (with a
confidence interval In frequentist statistics, a confidence interval (CI) is a range of estimates for an unknown parameter. A confidence interval is computed at a designated ''confidence level''; the 95% confidence level is most common, but other levels, such as 9 ...
between 60 cm and 2.89 metres), with some of that contribution coming from the EAIS. These findings were subsequently cited in the 2021 IPCC Sixth Assessment Report. If the warming were to remain at elevated levels for a long time, the East Antarctic Ice Sheet would eventually become the dominant contributor to sea level rise, simply because it contains far more ice than any other large ice mass. However, this would require very high warming and a lot of time: in 2022, an extensive assessment of
tipping points in the climate system In climate science, a tipping point is a critical threshold that, when crossed, leads to large and often irreversible changes in the climate system. If tipping points are crossed, they are likely to have severe impacts on human society. Tippin ...
published in the Science Magazine concluded that it would most likely be committed to complete ice loss only once the global warming reaches 7.5°C: the absolute minimum level would be at 5°C, but it could just as easily bet at 10°C. Likewise, the absolute minimum timescale for the complete disappearance of the EAIS even under those conditions is 10,000 years. If it were to disappear, then the change in ice-albedo feedback would increase the global temperature by 0.6°C, while the regional temperatures would increase by around 2°C. However, Wilkes Basin and several other subglacial basins like the nearby Aurora Basin are a lot more vulnerable, and could be committed to irreversible loss around 3°C, with a range between 2°C and 6°C. Their collapse would then take between 500 and 10,000 years (with a median of 2000 years), but would increase sea level by several metres even without involving the rest of the ice sheet. It has been estimated that during the
Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...
, the East Antarctic Ice Sheet thinned by at least , and that thinning since the
Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Late Glacial Maximum, was the most recent time during the Last Glacial Period that ice sheets were at their greatest extent. Ice sheets covered much of Northern North America, Northern Eu ...
is less than and probably started after ca 14 ka.


Territorial claims

Many countries hold a claim on portions of Antarctica. Within EAIS, the
United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and ...
,
France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...
,
Norway Norway, officially the Kingdom of Norway, is a Nordic countries, Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of ...
,
Australia Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. With an area of , Australia is the largest country by ...
,
Chile Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the eas ...
and
Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the List of South American countries by area, second-largest ...
all claim a portion (sometimes overlapping) as their own territory.


See also

*
Antarctic ice sheet The Antarctic ice sheet is one of the two polar ice caps of Earth. It covers about 98% of the Antarctic continent and is the largest single mass of ice on Earth, with an average thickness of over 2 kilometers. It covers an area of almost and ...
*
Scientific consensus on climate change There is 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 org ...


References


External links


E. J. Steig summary of paper on warming in West Antarctica referenced herein


{{coord, 80, S, 60, E, type:landmark_region:AQ_dim:10000000, display=title Ice sheets of Antarctica East Antarctica