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Coordinates: 80°S 60°E / 80°S 60°E / -80; 60
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Expansion, based on the material recently added to Climate change in Antarctica. Added an explanation of atmospheric temperature inversion as a key reason for its low sensitivity to climate change.
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The '''East Antarctic Ice Sheet''' ('''EAIS''') lies between [[45th meridian west|45° west]] and [[168th meridian east|168° east]] longitudinally. It was first formed around 34 million years ago,<ref name="Galeotti2016" /> and it is the largest [[ice sheet]] on the entire planet, with far greater volume than the [[Greenland ice sheet]] or the [[West Antarctic Ice Sheet]] (WAIS), from which it is separated by the [[Transantarctic Mountains]]. The ice sheet is around {{Convert|2.2|km|mi|abbr=on}} thick on average and is {{Convert|4897|m|ft|abbr=on}} at its thickest point.<ref name="Fretwell2013">{{Cite journal|last1=Fretwell|first1=P.|last2=Pritchard|first2=H. D.|last3=Vaughan|first3=D. G.|last4=Bamber|first4=J. L.|last5=Barrand|first5=N. E.|last6=Bell|first6=R.|last7=Bianchi|first7=C.|last8=Bingham|first8=R. G.|last9=Blankenship|first9=D. D.|date=2013-02-28|title=Bedmap2: improved ice bed, surface and thickness datasets for Antarctica|journal=The Cryosphere|volume=7|issue=1|pages=375–393|doi=10.5194/tc-7-375-2013|issn=1994-0424|doi-access=free|bibcode=2013TCry....7..375F|hdl=1808/18763|hdl-access=free}}</ref> It is also home to the geographic [[South Pole]] and the [[Amundsen–Scott South Pole Station]].
The '''East Antarctic Ice Sheet''' ('''EAIS''') lies between [[45th meridian west|45° west]] and [[168th meridian east|168° east]] longitudinally. It was first formed around 34 million years ago,<ref name="Galeotti2016" /> and it is the largest [[ice sheet]] on the entire planet, with far greater volume than the [[Greenland ice sheet]] or the [[West Antarctic Ice Sheet]] (WAIS), from which it is separated by the [[Transantarctic Mountains]]. The ice sheet is around {{Convert|2.2|km|mi|abbr=on}} thick on average and is {{Convert|4897|m|ft|abbr=on}} at its thickest point.<ref name="Fretwell2013">{{Cite journal|last1=Fretwell|first1=P.|last2=Pritchard|first2=H. D.|last3=Vaughan|first3=D. G.|last4=Bamber|first4=J. L.|last5=Barrand|first5=N. E.|last6=Bell|first6=R.|last7=Bianchi|first7=C.|last8=Bingham|first8=R. G.|last9=Blankenship|first9=D. D.|date=2013-02-28|title=Bedmap2: improved ice bed, surface and thickness datasets for Antarctica|journal=The Cryosphere|volume=7|issue=1|pages=375–393|doi=10.5194/tc-7-375-2013|issn=1994-0424|doi-access=free|bibcode=2013TCry....7..375F|hdl=1808/18763|hdl-access=free}}</ref> It is also home to the geographic [[South Pole]] and the [[Amundsen–Scott South Pole Station]].


The surface of the EAIS is the driest, windiest, and coldest place on Earth. Lack of moisture in the air, high [[albedo]] from the snow as well as the surface's consistently high elevation<ref name="Singh2020" /> results in the reported cold temperature records of nearly −{{cvt|100|C|F}}.<ref name="Scambos2018" /><ref name="VizcarraNSIDC2018" /> Because of that, it has been practically the only place on Earth to have experienced little-to-no [[climate change|warming]] caused by [[greenhouse gas emissions]] in the recent years.<ref name="Singh2020" />
The surface of the EAIS is the driest, windiest, and coldest place on Earth. Lack of moisture in the air, high [[albedo]] from the snow as well as the surface's consistently high elevation<ref name="Singh2020" /> results in the reported cold temperature records of nearly −{{cvt|100|C|F}}.<ref name="Scambos2018" /><ref name="VizcarraNSIDC2018" /> It is the only place on Earth cold enough for atmospheric temperature inversion to occur consistently. That is, while the [[atmosphere]] is typically warmest near the surface and becomes cooler at greater elevation, atmosphere during the Antarctic winter is cooler at the surface than in its middle layers. Consequently, [[greenhouse gas]]es actually trap heat in the middle atmosphere and reduce its flow towards the surface while the temperature inversion lasts.<ref name="Singh2020" />


Due to these factors, East Antarctica had experienced slight cooling for decades while the rest of the world warmed as the result of [[climate change]]. Clear warming over East Antarctica only started to occur since the year 2000, and was not conclusively detected until the 2020s.<ref name="Xin2023a" /><ref name="Xin2023b" /> In the early 2000s, cooling over East Antarctica seemingly outweighing warming over the rest of the continent was frequently [[media coverage of climate change|misinterpeted by the media]] and occasionally used as an argument for [[climate change denial]].<ref name="SFGateKeay2002">{{cite news |last=Davidson |first=Keay |date=2002-02-04 |title=Media goofed on Antarctic data / Global warming interpretation irks scientists |work=[[San Francisco Chronicle]] |url=http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2002/02/04/MN159039.DTL |access-date=2013-04-13}}</ref><ref name="RealClim">{{Cite web| url=http://www.realclimate.org/index.php?p=18 |author1=Eric Steig |author2=Gavin Schmidt |title=Antarctic cooling, global warming? |publisher=[[Real Climate]] | date=2004-12-03 | access-date=2008-08-14 |quote="At first glance this seems to contradict the idea of "global" warming, but one needs to be careful before jumping to this conclusion. A rise in the global mean temperature does not imply universal warming. Dynamical effects (changes in the winds and ocean circulation) can have just as large an impact, locally as the radiative forcing from greenhouse gases. The temperature change in any particular region will in fact be a combination of radiation-related changes (through greenhouse gases, aerosols, ozone and the like) and dynamical effects. Since the winds tend to only move heat from one place to another, their impact will tend to cancel out in the global mean." }}</ref><ref name="DoranNYT">{{Cite news| url=https://www.nytimes.com/2006/07/27/opinion/27doran.html | author=Peter Doran |title=Cold, Hard Facts |newspaper=[[The New York Times]] | date=2006-07-27 | access-date=2008-08-14 | archive-url= https://web.archive.org/web/20090411124340/http://www.nytimes.com/2006/07/27/opinion/27doran.html| archive-date=April 11, 2009| url-status= live}}</ref> After 2009, improvements in Antarctica's [[instrumental temperature record]] have proven that the warming over [[West Antarctica]] resulted in consistent net warming across the continent since the 1957.<ref name="SteigSchneider2009">{{cite journal |last1=Steig |first1=E. J. |last2=Schneider |first2=D. P. |last3=Rutherford |first3=S. D. |last4=Mann |first4=M. E. |last5=Comiso |first5=J. C. |last6=Shindell |first6=D. T. |year=2009 |title=Warming of the Antarctic ice-sheet surface since the 1957 International Geophysical Year |journal=[[Nature (journal)|Nature]] |url=https://docs.rwu.edu/fcas_fp/313 |volume=457 |issue=7228 |pages=459–462 |doi=10.1038/nature07669 |pmid=19158794 |bibcode=2009Natur.457..459S |s2cid=4410477 }}</ref>
The East Antarctic ice sheet is most likely to first see sustained losses of ice at its most vulnerable locations such as [[Totten Glacier]] and [[Wilkes Basin]]. Those areas are sometimes collectively described as East Antarctica's subglacial basins, and it is believed that once the warming reaches around {{convert|3|C-change|F-change}}, then they would start to collapse over a period of around 2,000 years,<ref name="ArmstrongMcKay2022" /><ref name="ArmstrongMcKayExplainer" /> This collapse would ultimately add between {{convert|1.4|m|ftin|abbr=on}} and {{convert|6.4|m|ftin|abbr=on}} to sea levels, depending on the [[ice sheet model]] used.<ref name="Pan2021" /> The EAIS as a whole holds enough ice to raise global sea levels by {{Convert|53.3|m|ft|abbr=on}}.<ref name="Fretwell2013" /> However, it would take global warming in a range between {{convert|5|C-change|F-change}} and {{convert|10|C-change|F-change}}, and a minimum of 10,000 years for the entire ice sheet to be lost.<ref name="ArmstrongMcKay2022" /><ref name="ArmstrongMcKayExplainer" />

Because the East Antarctic ice sheet has barely warmed, it is still gaining ice on average.<ref name="Zwally2021">{{Cite journal |last1=Zwally |first1=H. Jay |last2=Robbins |first2=John W. |last3=Luthcke |first3=Scott B. |last4=Loomis |first4=Bryant D. |last5=Rémy |first5=Frédérique |date=29 March 2021 |title=Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |journal=Journal of Glaciology |language=en |volume=67 |issue=263 |pages=533-559 |doi=10.1017/jog.2021.8 |doi-access=free |quote=Although their methods of interpolation or extrapolation for areas with unobserved output velocities have an insufficient description for the evaluation of associated errors, such errors in previous results (Rignot and others, 2008) caused large overestimates of the mass losses as detailed in Zwally and Giovinetto (Zwally and Giovinetto, 2011).}}</ref><ref name="NASA2023">{{cite web |title=Antarctic Ice Mass Loss 2002-2023 |url=https://svs.gsfc.nasa.gov/31158 |author=NASA |date=7 July 2023 }}</ref> for instance, [[GRACE and GRACE-FO|GRACE satellite]] data indicated East Antarctica mass gain of {{nowrap|60 ± 13}} billion tons per year between 2002 to 2010.<ref name="King2012">{{Cite journal | last1 = King | first1 = M. A. | last2 = Bingham | first2 = R. J. | last3 = Moore | first3 = P. | last4 = Whitehouse | first4 = P. L. | last5 = Bentley | first5 = M. J. | last6 = Milne | first6 = G. A. | doi = 10.1038/nature11621 | title = Lower satellite-gravimetry estimates of Antarctic sea-level contribution | journal = Nature | volume = 491 | issue = 7425 | pages = 586–589 | year = 2012 | pmid = 23086145|bibcode = 2012Natur.491..586K | s2cid = 4414976 }}</ref> It is most likely to first see sustained losses of ice at its most vulnerable locations such as [[Totten Glacier]] and [[Wilkes Basin]]. Those areas are sometimes collectively described as East Antarctica's subglacial basins, and it is believed that once the warming reaches around {{convert|3|C-change|F-change}}, then they would start to collapse over a period of around 2,000 years,<ref name="ArmstrongMcKay2022" /><ref name="ArmstrongMcKayExplainer" /> This collapse would ultimately add between {{convert|1.4|m|ftin|abbr=on}} and {{convert|6.4|m|ftin|abbr=on}} to sea levels, depending on the [[ice sheet model]] used.<ref name="Pan2021" /> The EAIS as a whole holds enough ice to raise global sea levels by {{Convert|53.3|m|ft|abbr=on}}.<ref name="Fretwell2013" /> However, it would take global warming in a range between {{convert|5|C-change|F-change}} and {{convert|10|C-change|F-change}}, and a minimum of 10,000 years for the entire ice sheet to be lost.<ref name="ArmstrongMcKay2022" /><ref name="ArmstrongMcKayExplainer" />


== Description ==
== Description ==
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East Antarctic Ice Sheet is located directly above the [[East Antarctic Shield]] - a [[craton]] (stable area of the [[Earth's crust]]) with the area of {{cvt|10,200,000|sqkm|sqmi}}, which accounts for around 73% of the entire Antarctic landmass.<ref name="Drewry1976">{{cite journal|last=Drewry|first=David J.|title=Sedimentary basins of the east antarctic craton from geophysical evidence|journal=Tectonophysics|date=November 1976|volume=36|issue=1–3|pages=301–314|bibcode=1976Tectp..36..301J|doi=10.1016/0040-1951(76)90023-8}}</ref> [[East Antarctica]] is separate from [[West Antarctica]] due to the presence of [[Transantarctic Mountains]], which span nearly {{cvt|3,500|km|mi}} from the [[Weddell Sea]] to the [[Ross Sea]], and have a width of {{cvt|100-300|km|mi}}.<ref name="Torsvik2008">{{cite book|last1=Torsvik|first1=T. H.|first2=C. |last2=Gaina |first3=T. F. |last3=Redfield|chapter=Antarctica and Global Paleogeography: From Rodinia, Through Gondwanaland and Pangea, to the Birth of the Southern Ocean and the Opening of Gateways|title=Antarctica: A Keystone in a Changing World|year=2008|pages=125–140|chapter-url=http://www.nap.edu/openbook.php?record_id=12168&page=125|doi=10.17226/12168|isbn=978-0-309-11854-5}}</ref>
East Antarctic Ice Sheet is located directly above the [[East Antarctic Shield]] - a [[craton]] (stable area of the [[Earth's crust]]) with the area of {{cvt|10,200,000|sqkm|sqmi}}, which accounts for around 73% of the entire Antarctic landmass.<ref name="Drewry1976">{{cite journal|last=Drewry|first=David J.|title=Sedimentary basins of the east antarctic craton from geophysical evidence|journal=Tectonophysics|date=November 1976|volume=36|issue=1–3|pages=301–314|bibcode=1976Tectp..36..301J|doi=10.1016/0040-1951(76)90023-8}}</ref> [[East Antarctica]] is separate from [[West Antarctica]] due to the presence of [[Transantarctic Mountains]], which span nearly {{cvt|3,500|km|mi}} from the [[Weddell Sea]] to the [[Ross Sea]], and have a width of {{cvt|100-300|km|mi}}.<ref name="Torsvik2008">{{cite book|last1=Torsvik|first1=T. H.|first2=C. |last2=Gaina |first3=T. F. |last3=Redfield|chapter=Antarctica and Global Paleogeography: From Rodinia, Through Gondwanaland and Pangea, to the Birth of the Southern Ocean and the Opening of Gateways|title=Antarctica: A Keystone in a Changing World|year=2008|pages=125–140|chapter-url=http://www.nap.edu/openbook.php?record_id=12168&page=125|doi=10.17226/12168|isbn=978-0-309-11854-5}}</ref>


The ice sheet has an average thickness of around {{Convert|2.2|km|mi|abbr=on}}. The thickest ice in Antarctica is located near [[Adelie Land]] close to the ice sheet's southeast coast, at the [[Astrolabe Subglacial Basin]], where it measured {{Convert|4897|m|ft|abbr=on}} around 2013.<ref name="Torsvik2008" /><ref name="Fretwell2013"/> Much of the ice sheet is already located at a high elevation: in particular, [[Dome Argus]] Plateau has an average height of around {{Convert|4|km|mi|abbr=on}}, and yet it is underlain by the [[Gamburtsev Mountain Range]], which has the average height of {{Convert|2.7|km|mi|abbr=on}} and is about equivalent in size to the European [[Alps]].<ref name= "PrattEARTH2012">{{cite web |author=Sara E. Pratt |date=6 February 2012 |title=Unearthing Antarctica's mysterious mountains |url=https://www.earthmagazine.org/article/unearthing-antarcticas-mysterious-mountains |publisher=[[Earth Magazine]] |accessdate=15 January 2024 }}</ref><ref name= "BellSciAm2008">{{cite web |author=Robin Bell |date=12 November 2008 |title=Dispatches from the Bottom of the Earth: An Antarctic Expedition in Search of Large Mountains Encased in Ice |url=https://www.scientificamerican.com/article/antarctic-expedition-in-search-of-lost-mountains/ |publisher=[[Scientific American]] |accessdate=15 January 2024 }}</ref> Consequently, the ice thickness over these mountains ranges from around {{Convert|1|km|mi|abbr=on}} over their peaks to about {{Convert|3|km|mi|abbr=on}} over the valleys.<ref name="EAISDavies">{{cite web |last=Davies |first=Bethan |title=East Antarctic Ice Sheet |url=https://www.antarcticglaciers.org/antarctica-2/east-antarctic-ice-sheet/ |website=AntarcticGlaciers.org |date=22 June 2020 }}</ref>
The ice sheet has an average thickness of around {{Convert|2.2|km|mi|abbr=on}}. The thickest ice in Antarctica is located near [[Adelie Land]] close to the ice sheet's southeast coast, at the [[Astrolabe Subglacial Basin]], where it measured {{Convert|4897|m|ft|abbr=on}} around 2013.<ref name="Torsvik2008" /> Much of the ice sheet is already located at a high elevation: in particular, [[Dome Argus]] Plateau has an average height of around {{Convert|4|km|mi|abbr=on}}, and yet it is underlain by the [[Gamburtsev Mountain Range]], which has the average height of {{Convert|2.7|km|mi|abbr=on}} and is about equivalent in size to the European [[Alps]].<ref name= "PrattEARTH2012">{{cite web |author=Sara E. Pratt |date=6 February 2012 |title=Unearthing Antarctica's mysterious mountains |url=https://www.earthmagazine.org/article/unearthing-antarcticas-mysterious-mountains |publisher=[[Earth Magazine]] |accessdate=15 January 2024 }}</ref><ref name= "BellSciAm2008">{{cite web |author=Robin Bell |date=12 November 2008 |title=Dispatches from the Bottom of the Earth: An Antarctic Expedition in Search of Large Mountains Encased in Ice |url=https://www.scientificamerican.com/article/antarctic-expedition-in-search-of-lost-mountains/ |publisher=[[Scientific American]] |accessdate=15 January 2024 }}</ref> Consequently, the ice thickness over these mountains ranges from around {{Convert|1|km|mi|abbr=on}} over their peaks to about {{Convert|3|km|mi|abbr=on}} over the valleys.<ref name="EAISDavies">{{cite web |last=Davies |first=Bethan |title=East Antarctic Ice Sheet |url=https://www.antarcticglaciers.org/antarctica-2/east-antarctic-ice-sheet/ |website=AntarcticGlaciers.org |date=22 June 2020 }}</ref>
[[File:South_Pole_Dome_From_Station.JPG|thumb|left|[[South Pole]] research station.]]
[[File:South_Pole_Dome_From_Station.JPG|thumb|left|[[South Pole]] research station.]]
These high elevations are an important reason for why the ice sheet is the driest, windiest, and coldest place on Earth. Dome A in particular sets reported cold temperature records of nearly −{{cvt|100|C|F}}.<ref name="Scambos2018">{{cite journal |last1=Scambos |first1=T. A. |last2=Campbell |first2=G. G. |last3=Pope |first3=A. |last4=Haran |first4=T. |last5=Muto |first5=A. |last6=Lazzara |first6=M. |last7=Reijmer |first7=C. H. |last8=Van Den Broeke |first8=M. R. |date=25 June 2018 |title=Ultralow Surface Temperatures in East Antarctica From Satellite Thermal Infrared Mapping: The Coldest Places on Earth |journal=Geophysical Research Letters |volume=45 |issue=12 |pages=6124–6133 |doi=10.1029/2018GL078133 |bibcode=2018GeoRL..45.6124S |hdl=1874/367883 |doi-access=free |hdl-access=free }}</ref><ref name="VizcarraNSIDC2018">{{Cite web |last=Vizcarra |first=Natasha |url=https://nsidc.org/news-analyses/news-stories/new-study-explains-antarcticas-coldest-temperatures |date=25 June 2018 |title=New study explains Antarctica's coldest temperatures |publisher=[[National Snow and Ice Data Center]] |language=en |access-date=10 January 2024 }}</ref><ref name="Singh2020">{{Cite journal |last1=Singh |first1=Hansi A. |last2=Polvani |first2=Lorenzo M. |date=10 January 2020 |title=Low Antarctic continental climate sensitivity due to high ice sheet orography |journal=npj Climate and Atmospheric Science |language=en |volume=3 |doi=10.1038/s41612-020-00143-w |s2cid=222179485 |doi-access=free }}</ref> The only ice-free areas of East Antarctica are where there is too little annual [[precipitation]] to form an ice layer, which is the case in the so-called Dry Valleys of the [[Southern Victoria Land]]. Another exception are the [[subglacial lake]]s, which occur so deep beneath the ice that the [[pressure melting point]] is well below {{cvt|0|C|F}}.<ref name="EAISDavies">{{cite web |last=Davies |first=Bethan |title=East Antarctic Ice Sheet |url=https://www.antarcticglaciers.org/antarctica-2/east-antarctic-ice-sheet/ |website=AntarcticGlaciers.org |date=22 June 2020 }}</ref>
These high elevations are an important reason for why the ice sheet is the driest, windiest, and coldest place on Earth. Dome A in particular sets reported cold temperature records of nearly −{{cvt|100|C|F}}.<ref name="Scambos2018">{{cite journal |last1=Scambos |first1=T. A. |last2=Campbell |first2=G. G. |last3=Pope |first3=A. |last4=Haran |first4=T. |last5=Muto |first5=A. |last6=Lazzara |first6=M. |last7=Reijmer |first7=C. H. |last8=Van Den Broeke |first8=M. R. |date=25 June 2018 |title=Ultralow Surface Temperatures in East Antarctica From Satellite Thermal Infrared Mapping: The Coldest Places on Earth |journal=Geophysical Research Letters |volume=45 |issue=12 |pages=6124–6133 |doi=10.1029/2018GL078133 |bibcode=2018GeoRL..45.6124S |hdl=1874/367883 |doi-access=free |hdl-access=free }}</ref><ref name="VizcarraNSIDC2018">{{Cite web |last=Vizcarra |first=Natasha |url=https://nsidc.org/news-analyses/news-stories/new-study-explains-antarcticas-coldest-temperatures |date=25 June 2018 |title=New study explains Antarctica's coldest temperatures |publisher=[[National Snow and Ice Data Center]] |language=en |access-date=10 January 2024 }}</ref><ref name="Singh2020">{{Cite journal |last1=Singh |first1=Hansi A. |last2=Polvani |first2=Lorenzo M. |date=10 January 2020 |title=Low Antarctic continental climate sensitivity due to high ice sheet orography |journal=npj Climate and Atmospheric Science |language=en |volume=3 |doi=10.1038/s41612-020-00143-w |s2cid=222179485 |doi-access=free }}</ref> The only ice-free areas of East Antarctica are where there is too little annual [[precipitation]] to form an ice layer, which is the case in the so-called [[McMurdo Dry Valleys]] of the [[Southern Victoria Land]]. Another exception are the [[subglacial lake]]s, which occur so deep beneath the ice that the [[pressure melting point]] is well below {{cvt|0|C|F}}.<ref name="EAISDavies">{{cite web |last=Davies |first=Bethan |title=East Antarctic Ice Sheet |url=https://www.antarcticglaciers.org/antarctica-2/east-antarctic-ice-sheet/ |website=AntarcticGlaciers.org |date=22 June 2020 }}</ref>


Many countries have made [[territorial claims in Antarctica]]. Within EAIS, the [[British Antarctic Territory|United Kingdom]], [[French Antarctic Territory|France]], [[Norwegian Antarctic territories|Norway]], [[Australian Antarctic Territory|Australia]], [[Chilean Antarctic Territory|Chile]] and [[Argentine Antarctica|Argentina]] all claim a portion (sometimes overlapping) as their own territory.<ref>{{Cite journal |last1=Bush |first1=W. M. |date=October 1989 |title=Antarctica and international law: a collection of inter-state and national documents |journal=American Journal of International Law |language=en |volume=83 |issue=4 |pages=959-964 |doi=10.2307/2203393 |isbn=978-0-379-20321-9 }}</ref>
Many countries have made [[territorial claims in Antarctica]]. Within EAIS, the [[British Antarctic Territory|United Kingdom]], [[French Antarctic Territory|France]], [[Norwegian Antarctic territories|Norway]], [[Australian Antarctic Territory|Australia]], [[Chilean Antarctic Territory|Chile]] and [[Argentine Antarctica|Argentina]] all claim a portion (sometimes overlapping) as their own territory.<ref>{{Cite journal |last1=Bush |first1=W. M. |date=October 1989 |title=Antarctica and international law: a collection of inter-state and national documents |journal=American Journal of International Law |language=en |volume=83 |issue=4 |pages=959-964 |doi=10.2307/2203393 |isbn=978-0-379-20321-9 }}</ref>
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== Recent climate change ==
== Recent climate change ==
[[File:Xin 2023 AIS SAT trends.jpg|thumb|East Antarctica had demonstrated cooling in the 1980s and 1990s, even as the West Antarctica warmed (left-hand side). This trend had largely reversed in 2000s and 2010s (right-hand side).<ref name="Xin2023" />]]
[[File:Xin 2023 AIS SAT trends.jpg|thumb|East Antarctica had demonstrated cooling in the 1980s and 1990s, even as the West Antarctica warmed (left-hand side). This trend had largely reversed in 2000s and 2010s (right-hand side).<ref name="Xin2023" />]]
Antarctica as a whole has low sensitivity to [[climate change]] because it is surrounded by the [[Southern Ocean]], which is more effective at absorbing heat than any other ocean due to the currents of the [[Southern Ocean overturning circulation]],<ref name="Bourgeois2022">{{cite journal |last1=Bourgeois |first1=Timothée |last2=Goris |first2=Nadine |last3=Schwinger |first3=Jörg |last4=Tjiputra |first4=Jerry F. |date=17 January 2022 |title=Stratification constrains future heat and carbon uptake in the Southern Ocean between 30°S and 55°S |journal=Nature Communications |volume=13 |issue=1 |page=340 |doi=10.1038/s41467-022-27979-5 |pmid=35039511 |pmc=8764023 |bibcode=2022NatCo..13..340B}}</ref><ref name="GTPR2023">{{cite report |last1=Lenton |first1=T. M. |last2=Armstrong McKay |first2=D.I. |last3=Loriani |first3=S. |last4=Abrams |first4=J.F. |last5=Lade |first5=S.J. |last6=Donges |first6=J.F. |last7=Milkoreit |first7=M. |last8=Powell |first8=T. |last9=Smith |first9=S.R. |last10=Zimm |first10=C. |last11=Buxton |first11=J.E. |last12=Daube |first12=Bruce C. |last13=Krummel |first13=Paul B. |last14=Loh |first14=Zoë |last15=Luijkx |first15=Ingrid T. |year=2023 |title=The Global Tipping Points Report 2023 |url=https://global-tipping-points.org/download/4608/ |publisher=University of Exeter}}</ref> and because of the high [[albedo]] (reflectivity) of its icy surface and of the surrounding [[sea ice]].<ref name="Singh2020" /> These factors make Antarctica the coldest continent, and East Antarctica is additionally cooler than the West Antarctica, because it is located at a substantially greater elevation.<ref name="Singh2020" /> This makes it the only place on Earth cold enough for atmospheric temperature inversion to occur every winter.<ref name="Singh2020" /> While the [[atmosphere]] on Earth is at its warmest near the surface and becomes cooler as elevation increases, temperature inversion during the Antarctic winter results in middle layers of the atmosphere being warmer than the surface.<ref name="Singh2020" /> Thus, [[greenhouse gas]]es trap heat in the middle atmosphere and reduce its flow towards the surface and towards space, while normally, they prevent the flow of heat from the lower atmosphere and towards. This effect lasts until the end of the Antarctic winter.<ref name="Singh2020" />
Because East Antarctica is already cooler than West Antarctica, and is also located at substantially greater elevation,<ref name="Singh2020" /> it had been less sensitive to [[climate change]], and had actually experienced cooling in the 1980s and 1990s, even as the West Antarctic Ice Sheet has warmed by more than 0.1&nbsp;°C/decade since the 1950s.<ref name="SteigSchneider2009" /> After 2000, the trend had reversed due to local changes in atmospheric circulation: the warming of West Antarctica locations slowed or partially reversed between 2000 and 2020, while the East Antarctica interior had demonstated clear warming. This change in circulation had occurred partly due to natural variability, and partly as the result of the [[ozone layer]] beginning to recover following the [[Montreal Protocol]].<ref name="Xin2023">{{cite journal |last1=Xin |first1=Meijiao |last2=Clem |first2=Kyle R |last3=Turner |first3=John |last4=Stammerjohn |first4=Sharon E |last5=Zhu |first5=Jiang |last6=Cai |first6=Wenju |last7=Li |first7=Xichen |date=2 June 2023 |title=West-warming East-cooling trend over Antarctica reversed since early 21st century driven by large-scale circulation variation |journal=Environmental Research Letters |volume=18 |issue=6 |page=064034 |doi=10.1088/1748-9326/acd8d4 |doi-access=free }}</ref><ref>{{cite journal |last1=Xin |first1=Meijiao |last2=Li |first2=Xichen |last3=Stammerjohn |first3=Sharon E |last4=Cai |first4=Wenju |last5=Zhu |first5=Jiang |last6=Turner |first6=John |last7=Clem |first7=Kyle R |last8=Song |first8=Chentao |last9=Wang |first9=Wenzhu |last10=Hou |first10=Yurong |date=17 May 2023 |title=A broadscale shift in antarctic temperature trends |journal=Climate Dynamics |volume=61 |pages=4623–4641 |doi=10.1007/s00382-023-06825-4 }}</ref> The continent-wide average surface temperature trend of Antarctica is positive and [[Statistical significance|statistically significant]] at >0.05&nbsp;°C/decade since 1957.<ref name="SteigSchneider2009">{{cite journal |last1=Steig |first1=E. J. |last2=Schneider |first2=D. P. |last3=Rutherford |first3=S. D. |last4=Mann |first4=M. E. |last5=Comiso |first5=J. C. |last6=Shindell |first6=D. T. |year=2009 |title=Warming of the Antarctic ice-sheet surface since the 1957 International Geophysical Year |journal=[[Nature (journal)|Nature]] |url=https://docs.rwu.edu/fcas_fp/313 |volume=457 |issue=7228 |pages=459–462 |doi=10.1038/nature07669 |pmid=19158794 |bibcode=2009Natur.457..459S |s2cid=4410477 }}</ref>

Due to these factors, East Antarctica had experienced cooling in the 1980s and 1990s. For instance, between 1986 to 2006 there had been a cooling of 0.7&nbsp;°C per decade at [[Lake Hoare]] station in the [[McMurdo Dry Valleys]].<ref>{{Cite journal |last1=Obryk |first1=M. K. |last2=Doran |first2=P. T. |last3=Fountain |first3=A. G. |last4=Myers |first4=M. |last5=McKay |first5=C. P. |date=16 July 2020 |title=Climate From the McMurdo Dry Valleys, Antarctica, 1986–2017: Surface Air Temperature Trends and Redefined Summer Season |url=https://onlinelibrary.wiley.com/doi/10.1029/2019JD032180 |journal=Journal of Geophysical Research: Atmospheres |language=en |volume=125 |issue=13 |doi=10.1029/2019JD032180 |bibcode=2020JGRD..12532180O |s2cid=219738421 |issn=2169-897X}}</ref> A 2002 paper by [[Peter Doran]] suggested that the cooling over East Antarctica outweighed warming of the rest of the continent.<ref name="Doran2002">{{cite journal |last1=Doran |first1=Peter T. |last2=Priscu |first2=JC |last3=Lyons |first3=WB |last4=Walsh |first4=John E. |last5=Fountain |first5=Andrew G. |last6=McKnight |first6=Diane M. |last7=Moorhead |first7=Daryl L. |last8=Virginia |first8=Ross A. |last9=Wall |first9=Diana H. |last10=D. |first10=Gary |last11=H. |first11=Christian |display-authors=3 |date=January 2002 |title=Antarctic climate cooling and terrestrial ecosystem response |url=http://www.uic.edu/classes/geol/eaes102/Doran.pdf |journal=Nature |volume=415 |issue=6871 |pages=517–20 |doi=10.1038/nature710 |pmid=11793010 |s2cid=387284 |archive-url=https://web.archive.org/web/20041211081457/http://www.uic.edu/classes/geol/eaes102/Doran.pdf |archive-date=11 December 2004}}</ref> While the paper estimated that about 42% of the Antarctic area had been warming, it was wrongly described by many media outlets as a proof that there was no warming in Antarctica.<ref name="SFGateKeay2002" /> In 2004, author [[Michael Crichton]] used that cooling as one of his arguments for [[climate change denial|denying climate change]] in his novel ''[[State of Fear]]''.<ref name= "State_of_Fear">{{Cite book| last = Crichton| first = Michael| year = 2004| title = State of Fear| publisher = [[HarperCollins]], New York| isbn = 978-0-06-621413-9 |page=109 |url=https://archive.org/details/stateoffearnove000cric/page/109 | url-access = registration |quote=The data show that one relatively small area called the Antarctic Peninsula is melting and [[Ice calving|calving]] huge icebergs. That's what gets reported year after year. But the continent as a whole is getting colder, and the ice is getting thicker.}} First Edition</ref> First other scientists, and then Peter Doran himself eventually had to debunk the book's claims.<ref name="RealClim" /><ref name="DoranNYT"/> In 2009, it was demonstrated that the West Antarctic Ice Sheet has warmed by more than 0.1&nbsp;°C/decade since the 1950s, resulting in a [[Statistical significance|statistically significant]] warming trend across Antarctica of >0.05&nbsp;°C/decade since 1957.<ref name="SteigSchneider2009" /> Later research found that after 2000, the warming of West Antarctica locations slowed or partially reversed between 2000 and 2020, while the East Antarctica interior had demonstated clear warming. This happened due to the local changes in [[Southern Annular Mode]] the dominant [[climate variability]] pattern over the Antarctica. Some of those changes were caused by the [[ozone layer]] beginning to recover following the [[Montreal Protocol]].<ref name="Xin2023a">{{cite journal |last1=Xin |first1=Meijiao |last2=Clem |first2=Kyle R |last3=Turner |first3=John |last4=Stammerjohn |first4=Sharon E |last5=Zhu |first5=Jiang |last6=Cai |first6=Wenju |last7=Li |first7=Xichen |date=2 June 2023 |title=West-warming East-cooling trend over Antarctica reversed since early 21st century driven by large-scale circulation variation |journal=Environmental Research Letters |volume=18 |issue=6 |page=064034 |doi=10.1088/1748-9326/acd8d4 |doi-access=free }}</ref><ref name="Xin2023b">{{cite journal |last1=Xin |first1=Meijiao |last2=Li |first2=Xichen |last3=Stammerjohn |first3=Sharon E |last4=Cai |first4=Wenju |last5=Zhu |first5=Jiang |last6=Turner |first6=John |last7=Clem |first7=Kyle R |last8=Song |first8=Chentao |last9=Wang |first9=Wenzhu |last10=Hou |first10=Yurong |date=17 May 2023 |title=A broadscale shift in antarctic temperature trends |journal=Climate Dynamics |volume=61 |pages=4623–4641 |doi=10.1007/s00382-023-06825-4 }}</ref>
[[File:Denman_oli_2020-057-059_lrg-labeled.svg|thumb|Aerial view of ice flows at Denman Glacier, one of the relatively few glaciers in the East Antarctica known to be losing mass.<ref name="Brancato2020" />]]
[[File:Denman_oli_2020-057-059_lrg-labeled.svg|thumb|Aerial view of ice flows at Denman Glacier, one of the relatively few glaciers in the East Antarctica known to be losing mass.<ref name="Brancato2020" />]]
The limited warming and already low temperatures over East Antarctica mean that as of early 2020s, the majority of observational evidence shows it continuing to gain mass.<ref name="King2012" /><ref name="IMBIE2018">{{cite journal |title=Mass balance of the Antarctic Ice Sheet from 1992 to 2017 |journal=Nature |date=13 June 2018 |volume=558 |issue=7709 |pages=219–222 |doi=10.1038/s41586-018-0179-y |hdl=2268/225208 |pmid=29899482 |bibcode=2018Natur.558..219I |author1=IMBIE team |s2cid=49188002 |hdl-access=free }}</ref><ref name="Zwally2021" /><ref name="NASA2023">{{cite web |title=Antarctic Ice Mass Loss 2002-2023 |url=https://svs.gsfc.nasa.gov/31158 |author=NASA |date=7 July 2023 }}</ref> for instance, [[GRACE and GRACE-FO|GRACE satellite]] data indicated East Antarctica mass gain of {{nowrap|60 ± 13}} billion tons per year between 2002 to 2010.<ref name="King2012">{{Cite journal | last1 = King | first1 = M. A. | last2 = Bingham | first2 = R. J. | last3 = Moore | first3 = P. | last4 = Whitehouse | first4 = P. L. | last5 = Bentley | first5 = M. J. | last6 = Milne | first6 = G. A. | doi = 10.1038/nature11621 | title = Lower satellite-gravimetry estimates of Antarctic sea-level contribution | journal = Nature | volume = 491 | issue = 7425 | pages = 586–589 | year = 2012 | pmid = 23086145|bibcode = 2012Natur.491..586K | s2cid = 4414976 }}</ref> Some analyses have suggested it already begun to lose mass in 2000s,<ref>{{cite journal |last1=Chen |first1=J. L. |last2=Wilson |first2=C. R. |last3=Blankenship |first3=D. |last4=Tapley |first4=B. D. |year=2009 |title=Accelerated Antarctic ice loss from satellite gravity measurements |journal=Nature Geoscience |volume=2 |issue=12 |pages=859 |doi=10.1038/ngeo694 |bibcode=2009NatGe...2..859C |s2cid=130927366 }}</ref><ref>{{cite journal |last1=Rignot |first1=Eric |last2=Mouginot |first2=Jérémie |last3=Scheuchl |first3=Bernd |last4=van den Broeke |first4=Michiel |last5=van Wessem |first5=Melchior J. |last6=Morlighem |first6=Mathieu |title=Four decades of Antarctic Ice Sheet mass balance from 1979–2017 |journal=Proceedings of the National Academy of Sciences |date=22 January 2019 |volume=116 |issue=4 |pages=1095–1103 |doi=10.1073/pnas.1812883116 |pmid=30642972 |pmc=6347714 |bibcode=2019PNAS..116.1095R |doi-access=free }}</ref> but they over-extrapolated some observed losses onto the poorly-observed areas, and a more complete observational record shows continued mass gain.<ref name="Zwally2021">{{Cite journal |last1=Zwally |first1=H. Jay |last2=Robbins |first2=John W. |last3=Luthcke |first3=Scott B. |last4=Loomis |first4=Bryant D. |last5=Rémy |first5=Frédérique |date=29 March 2021 |title=Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry |journal=Journal of Glaciology |language=en |volume=67 |issue=263 |pages=533-559 |doi=10.1017/jog.2021.8 |quote=Although their methods of interpolation or extrapolation for areas with unobserved output velocities have an insufficient description for the evaluation of associated errors, such errors in previous results (Rignot and others, 2008) caused large overestimates of the mass losses as detailed in Zwally and Giovinetto (Zwally and Giovinetto, 2011).|doi-access=free }}</ref>
The limited warming and already low temperatures over East Antarctica mean that as of early 2020s, the majority of observational evidence shows it continuing to gain mass.<ref name="King2012" /><ref name="IMBIE2018">{{cite journal |title=Mass balance of the Antarctic Ice Sheet from 1992 to 2017 |journal=Nature |date=13 June 2018 |volume=558 |issue=7709 |pages=219–222 |doi=10.1038/s41586-018-0179-y |hdl=2268/225208 |pmid=29899482 |bibcode=2018Natur.558..219I |author1=IMBIE team |s2cid=49188002 |hdl-access=free }}</ref><ref name="Zwally2021" /><ref name="NASA2023" /> Some analyses have suggested it already began to lose mass in 2000s,<ref>{{cite journal |last1=Chen |first1=J. L. |last2=Wilson |first2=C. R. |last3=Blankenship |first3=D. |last4=Tapley |first4=B. D. |year=2009 |title=Accelerated Antarctic ice loss from satellite gravity measurements |journal=Nature Geoscience |volume=2 |issue=12 |pages=859 |doi=10.1038/ngeo694 |bibcode=2009NatGe...2..859C |s2cid=130927366 }}</ref><ref>{{cite journal |last1=Rignot |first1=Eric |last2=Mouginot |first2=Jérémie |last3=Scheuchl |first3=Bernd |last4=van den Broeke |first4=Michiel |last5=van Wessem |first5=Melchior J. |last6=Morlighem |first6=Mathieu |title=Four decades of Antarctic Ice Sheet mass balance from 1979–2017 |journal=Proceedings of the National Academy of Sciences |date=22 January 2019 |volume=116 |issue=4 |pages=1095–1103 |doi=10.1073/pnas.1812883116 |pmid=30642972 |pmc=6347714 |bibcode=2019PNAS..116.1095R |doi-access=free }}</ref> but they over-extrapolated some observed losses onto the poorly-observed areas, and a more complete observational record shows continued mass gain.<ref name="Zwally2021" />


[[File:1900-2300 Long-term projections of sea level rise.svg|thumb|If countries cut [[greenhouse gas]] emissions significantly (lowest trace), then [[sea level rise]] by 2100 can be limited to {{cvt|0.3–0.6|m|ft|frac=2}}.<ref name="NASA_SLR_2021"/> If the emissions instead accelerate rapidly (top trace), sea levels could rise {{cvt|5|m|ft|frac=2}} by the year 2300. Higher levels of sea level rise would involve ice loss from the East Antarctica.<ref name=NASA_SLR_2021>{{cite web |title=Anticipating Future Sea Levels |url=https://earthobservatory.nasa.gov/images/148494/anticipating-future-sea-levels |website=EarthObservatory.NASA.gov |publisher=National Aeronautics and Space Administration (NASA) |archive-url=https://web.archive.org/web/20210707220354/https://earthobservatory.nasa.gov/images/148494/anticipating-future-sea-levels |archive-date=7 July 2021 |date=2021 |url-status=live }}</ref>]]
[[File:1900-2300 Long-term projections of sea level rise.svg|thumb|If countries cut [[greenhouse gas]] emissions significantly (lowest trace), then [[sea level rise]] by 2100 can be limited to {{cvt|0.3–0.6|m|ft|frac=2}}.<ref name="NASA_SLR_2021"/> If the emissions instead accelerate rapidly (top trace), sea levels could rise {{cvt|5|m|ft|frac=2}} by the year 2300. Higher levels of sea level rise would involve ice loss from the East Antarctica.<ref name=NASA_SLR_2021>{{cite web |title=Anticipating Future Sea Levels |url=https://earthobservatory.nasa.gov/images/148494/anticipating-future-sea-levels |website=EarthObservatory.NASA.gov |publisher=National Aeronautics and Space Administration (NASA) |archive-url=https://web.archive.org/web/20210707220354/https://earthobservatory.nasa.gov/images/148494/anticipating-future-sea-levels |archive-date=7 July 2021 |date=2021 |url-status=live }}</ref>]]
Because it is currently gaining mass, East Antarctic Ice Sheet is not expected to play a role in the 21st century [[sea level rise]]. However, it is still subject to adverse change, such as the retreat of [[Denman Glacier]],<ref name="Brancato2020">{{cite journal|last1=Brancato|first1=V.|last2=Rignot|first2=E.|last3=Milillo|first3=P.|last4=Morlighem|first4=M.|last5=Mouginot|first5=J.|last6=An|first6=L.|last7=Scheuchl|first7=B.|last8=Jeong|first8=S.|last9=Rizzoli|first9=P.|last10=Bueso Bello|first10=J.L.|last11=Prats-Iraola|first11=P.|title=Grounding line retreat of Denman Glacier, East Antarctica, measured with COSMO-SkyMed radar interferometry data|journal=Geophysical Research Letters|year=2020| volume=47 | issue=7 |pages=e2019GL086291|issn=0094-8276|doi=10.1029/2019GL086291| bibcode=2020GeoRL..4786291B |doi-access=free}}</ref><ref>{{cite news|newspaper=[[BBC]]|url=https://www.bbc.com/news/science-environment-52007637|title=Climate change: Earth's deepest ice canyon vulnerable to melting |last=Amos|first=Jonathan|date=2020-03-23}}</ref> or the flow of warmer ocean current into ice cavities beneath the stabilizing [[ice shelf|ice shelves]] like the [[Fimbul Ice Shelf|Fimbulisen]] ice shelf in the [[Queen Maud Land]].<ref>{{Cite journal |last=Lauber |first=Julius |last2=Hattermann |first2=Torr |last3=de Steur |first3=Laura |last4=Darelius |first4=Elin |last5=Auger |first5=Matthis |last6=Anders Nost |first6=Ole |last7=Moholdt |first7=Geir |date=21 September 2023 |title=Warming beneath an East Antarctic ice shelf due to increased subpolar westerlies and reduced sea ice |url=https://www.nature.com/articles/s41561-023-01273-5 |journal=Nature Geoscience |volume=16 |pages=877-885}}</ref> If global warming were to reach higher levels, then the EAIS would play an increasingly larger role in sea level rise occurring after 2100. According to the most recent reports of the [[Intergovernmental Panel on Climate Change]] ([[SROCC]] and the [[IPCC Sixth Assessment Report]]), the most intense [[climate change scenario]], where the anthropogenic emissions increase continuously, [[Representative Concentration Pathway|RCP8.5]], would result in Antarctica alone losing a [[median]] of {{convert|1.46|m|ftin|abbr=on}} ([[confidence interval]] between {{convert|60|cm|ft|abbr=on}} and {{convert|2.89|m|ftin|abbr=on}}), which would involve some loss from the EAIS in addition to the erosion of the WAIS. This Antarctica-only sea level rise would be in addition to ice losses from the [[Greenland ice sheet]] and [[retreat of glaciers since 1850|mountain glaciers]], as well as the [[thermal expansion]] of ocean water.<ref name="IPCC AR6 WG1 Ch.9">{{Cite journal |last1=Fox-Kemper |first1=B. |last2=Hewitt |first2=H.T.|author2-link=Helene Hewitt |last3=Xiao |first3=C. |last4=Aðalgeirsdóttir |first4=G. |last5=Drijfhout |first5=S.S. |last6=Edwards |first6=T.L. |last7=Golledge |first7=N.R. |last8=Hemer |first8=M. |last9=Kopp |first9=R.E. |last10=Krinner |first10=G. |last11=Mix |first11=A. |date=2021 |editor-last=Masson-Delmotte |editor-first=V. |editor2-last=Zhai |editor2-first=P. |editor3-last=Pirani |editor3-first=A. |editor4-last=Connors |editor4-first=S.L. |editor5-last=Péan |editor5-first=C. |editor6-last=Berger |editor6-first=S. |editor7-last=Caud |editor7-first=N. |editor8-last=Chen |editor8-first=Y. |editor9-last=Goldfarb |editor9-first=L. |title=Chapter 9: Ocean, Cryosphere and Sea Level Change |journal=Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |url=https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter09.pdf |publisher=Cambridge University Press, Cambridge, UK and New York, NY, USA |pages=1270–1272 }}</ref>
Because it is currently gaining mass, East Antarctic Ice Sheet is not expected to play a role in the 21st century [[sea level rise]]. However, it is still subject to adverse change, such as the retreat of [[Denman Glacier]],<ref name="Brancato2020">{{cite journal|last1=Brancato|first1=V.|last2=Rignot|first2=E.|last3=Milillo|first3=P.|last4=Morlighem|first4=M.|last5=Mouginot|first5=J.|last6=An|first6=L.|last7=Scheuchl|first7=B.|last8=Jeong|first8=S.|last9=Rizzoli|first9=P.|last10=Bueso Bello|first10=J.L.|last11=Prats-Iraola|first11=P.|title=Grounding line retreat of Denman Glacier, East Antarctica, measured with COSMO-SkyMed radar interferometry data|journal=Geophysical Research Letters|year=2020| volume=47 | issue=7 |pages=e2019GL086291|issn=0094-8276|doi=10.1029/2019GL086291| bibcode=2020GeoRL..4786291B |doi-access=free}}</ref><ref>{{cite news|newspaper=[[BBC]]|url=https://www.bbc.com/news/science-environment-52007637|title=Climate change: Earth's deepest ice canyon vulnerable to melting |last=Amos|first=Jonathan|date=2020-03-23}}</ref> or the flow of warmer ocean current into ice cavities beneath the stabilizing [[ice shelf|ice shelves]] like the [[Fimbul Ice Shelf|Fimbulisen]] ice shelf in the [[Queen Maud Land]].<ref>{{Cite journal |last=Lauber |first=Julius |last2=Hattermann |first2=Torr |last3=de Steur |first3=Laura |last4=Darelius |first4=Elin |last5=Auger |first5=Matthis |last6=Anders Nost |first6=Ole |last7=Moholdt |first7=Geir |date=21 September 2023 |title=Warming beneath an East Antarctic ice shelf due to increased subpolar westerlies and reduced sea ice |url=https://www.nature.com/articles/s41561-023-01273-5 |journal=Nature Geoscience |volume=16 |pages=877-885}}</ref> If global warming were to reach higher levels, then the EAIS would play an increasingly larger role in sea level rise occurring after 2100. According to the most recent reports of the [[Intergovernmental Panel on Climate Change]] ([[SROCC]] and the [[IPCC Sixth Assessment Report]]), the most intense [[climate change scenario]], where the anthropogenic emissions increase continuously, [[Representative Concentration Pathway|RCP8.5]], would result in Antarctica alone losing a [[median]] of {{convert|1.46|m|ftin|abbr=on}} ([[confidence interval]] between {{convert|60|cm|ft|abbr=on}} and {{convert|2.89|m|ftin|abbr=on}}) by 2300, which would involve some loss from the EAIS in addition to the erosion of the WAIS. This Antarctica-only sea level rise would be in addition to ice losses from the [[Greenland ice sheet]] and [[retreat of glaciers since 1850|mountain glaciers]], as well as the [[thermal expansion]] of ocean water.<ref name="IPCC AR6 WG1 Ch.9">{{Cite journal |last1=Fox-Kemper |first1=B. |last2=Hewitt |first2=H.T.|author2-link=Helene Hewitt |last3=Xiao |first3=C. |last4=Aðalgeirsdóttir |first4=G. |last5=Drijfhout |first5=S.S. |last6=Edwards |first6=T.L. |last7=Golledge |first7=N.R. |last8=Hemer |first8=M. |last9=Kopp |first9=R.E. |last10=Krinner |first10=G. |last11=Mix |first11=A. |date=2021 |editor-last=Masson-Delmotte |editor-first=V. |editor2-last=Zhai |editor2-first=P. |editor3-last=Pirani |editor3-first=A. |editor4-last=Connors |editor4-first=S.L. |editor5-last=Péan |editor5-first=C. |editor6-last=Berger |editor6-first=S. |editor7-last=Caud |editor7-first=N. |editor8-last=Chen |editor8-first=Y. |editor9-last=Goldfarb |editor9-first=L. |title=Chapter 9: Ocean, Cryosphere and Sea Level Change |journal=Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |url=https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter09.pdf |publisher=Cambridge University Press, Cambridge, UK and New York, NY, USA |pages=1270–1272 }}</ref>


== Long-term future ==
== Long-term future ==
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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. First, though, it would see sustained erosion at the so-called subglacial basins, such as [[Totten Glacier]] and [[Wilkes Basin]], which are located in vulnerable locations below the sea level. Estimates suggest that they would be committed to disappearance once the global warming reaches {{convert|3|C-change|F-change}}, although the plausible temperature range is between {{convert|2|C-change|F-change}} and {{convert|6|C-change|F-change}}. Once it becomes too warm for these subglacial basins, their collapse would unfold over a period of around 2,000 years, although it may be as fast as 500 years or as slow as 10,000 years.<ref name="ArmstrongMcKay2022" /><ref name="ArmstrongMcKayExplainer" /> The loss of all this ice would ultimately add between {{convert|1.4|m|ftin|abbr=on}} and {{convert|6.4|m|ftin|abbr=on}} to sea levels, depending on the [[ice sheet model]] used. [[Isostatic rebound]] of the newly ice-free land would also add {{convert|8|cm|ftin|abbr=on}} and {{convert|57|cm|ftin|abbr=on}}, respectively.<ref name="Pan2021">{{Cite journal|last1=Pan |first1=Linda |last2=Powell |first2=Evelyn M. |last3=Latychev |first3=Konstantin |last4=Mitrovica |first4=Jerry X. |last5=Creveling |first5=Jessica R. |last6=Gomez |first6=Natalya |last7=Hoggard |first7=Mark J. |last8=Clark |first8=Peter U. |date=30 April 2021 |title=Rapid postglacial rebound amplifies global sea level rise following West Antarctic Ice Sheet collapse |journal=Science Advances |volume=7 |issue=18 |doi=10.1126/sciadv.abf7787 }}</ref> Evidence from the [[Pleistocene]] shows that partial loss can also occur at lower warming levels: Wilkes Basin is estimated to have lost enough ice to add {{convert|0.5|m|ftin|abbr=on}} to sea levels between 115,000 and 129,000 years ago, during the [[Eemian]], and about {{convert|0.9|m|ftin|abbr=on}} between 318,000 and 339,000 years ago, during the [[Marine Isotope Stage 9]].<ref name="Crotti2022">{{cite journal |last1=Crotti |first1=Ilaria |last2=Quiquet |first2=Aurélien |last3=Landais |first3=Amaelle |last4=Stenni |first4=Barbara |last5=Wilson |first5=David J. |last6=Severi |first6=Mirko |last7=Mulvaney |first7=Robert |last8=Wilhelms |first8=Frank |last9=Barbante |first9=Carlo |last10=Frezzotti |first10=Massimo |date=10 September 2022 |title=Wilkes subglacial basin ice sheet response to Southern Ocean warming during late Pleistocene interglacials |journal=Nature Communications |volume=13 |pages=5328 |doi=10.1038/s41467-022-32847-3 |hdl=10278/5003813 |hdl-access=free }}</ref>
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. First, though, it would see sustained erosion at the so-called subglacial basins, such as [[Totten Glacier]] and [[Wilkes Basin]], which are located in vulnerable locations below the sea level. Estimates suggest that they would be committed to disappearance once the global warming reaches {{convert|3|C-change|F-change}}, although the plausible temperature range is between {{convert|2|C-change|F-change}} and {{convert|6|C-change|F-change}}. Once it becomes too warm for these subglacial basins, their collapse would unfold over a period of around 2,000 years, although it may be as fast as 500 years or as slow as 10,000 years.<ref name="ArmstrongMcKay2022" /><ref name="ArmstrongMcKayExplainer" /> The loss of all this ice would ultimately add between {{convert|1.4|m|ftin|abbr=on}} and {{convert|6.4|m|ftin|abbr=on}} to sea levels, depending on the [[ice sheet model]] used. [[Isostatic rebound]] of the newly ice-free land would also add {{convert|8|cm|ftin|abbr=on}} and {{convert|57|cm|ftin|abbr=on}}, respectively.<ref name="Pan2021">{{Cite journal|last1=Pan |first1=Linda |last2=Powell |first2=Evelyn M. |last3=Latychev |first3=Konstantin |last4=Mitrovica |first4=Jerry X. |last5=Creveling |first5=Jessica R. |last6=Gomez |first6=Natalya |last7=Hoggard |first7=Mark J. |last8=Clark |first8=Peter U. |date=30 April 2021 |title=Rapid postglacial rebound amplifies global sea level rise following West Antarctic Ice Sheet collapse |journal=Science Advances |volume=7 |issue=18 |doi=10.1126/sciadv.abf7787 }}</ref> Evidence from the [[Pleistocene]] shows that partial loss can also occur at lower warming levels: Wilkes Basin is estimated to have lost enough ice to add {{convert|0.5|m|ftin|abbr=on}} to sea levels between 115,000 and 129,000 years ago, during the [[Eemian]], and about {{convert|0.9|m|ftin|abbr=on}} between 318,000 and 339,000 years ago, during the [[Marine Isotope Stage 9]].<ref name="Crotti2022">{{cite journal |last1=Crotti |first1=Ilaria |last2=Quiquet |first2=Aurélien |last3=Landais |first3=Amaelle |last4=Stenni |first4=Barbara |last5=Wilson |first5=David J. |last6=Severi |first6=Mirko |last7=Mulvaney |first7=Robert |last8=Wilhelms |first8=Frank |last9=Barbante |first9=Carlo |last10=Frezzotti |first10=Massimo |date=10 September 2022 |title=Wilkes subglacial basin ice sheet response to Southern Ocean warming during late Pleistocene interglacials |journal=Nature Communications |volume=13 |pages=5328 |doi=10.1038/s41467-022-32847-3 |hdl=10278/5003813 |hdl-access=free }}</ref>


The entire East Antarctic Ice Sheet holds enough ice to raise global sea levels by {{Convert|53.3|m|ft|abbr=on}}.<ref name="Fretwell2013" /> Its complete melting is also possible, but it would require very high warming and a lot of time: in 2022, an extensive assessment of [[tipping points in the climate system]] published in the [[Science Magazine]] concluded that the ice sheet would most likely be committed to complete disappearance only once the global warming reaches about {{convert|7.5|C-change|F-change}}, with the minimum and the maximum range between {{convert|5|C-change|F-change}} and {{convert|10|C-change|F-change}}. It would also take a minimum of 10,000 years for the entire ice sheet to be lost. If it were to disappear, then the change in [[ice-albedo feedback]] would increase the global temperature by {{convert|0.6|C-change|F-change}}, while the regional temperatures would increase by around {{convert|2|C-change|F-change}}. The loss of the subglacial basins alone would only add about {{convert|0.05|C-change|F-change}} to global temperatures due to their relatively limited area.<ref name="ArmstrongMcKay2022">{{Cite journal |last1=Armstrong McKay |first1=David|last2=Abrams |first2=Jesse |last3=Winkelmann |first3=Ricarda |last4=Sakschewski |first4=Boris |last5=Loriani |first5=Sina |last6=Fetzer |first6=Ingo|last7=Cornell|first7=Sarah |last8=Rockström |first8=Johan |last9=Staal |first9=Arie |last10=Lenton |first10=Timothy |date=9 September 2022 |title=Exceeding 1.5°C global warming could trigger multiple climate tipping points |url=https://www.science.org/doi/10.1126/science.abn7950 |journal=Science |language=en |volume=377 |issue=6611 |doi=10.1126/science.abn7950 |hdl=10871/131584 |s2cid=252161375 |issn=0036-8075|hdl-access=free }}</ref><ref name="ArmstrongMcKayExplainer">{{Cite web |last=Armstrong McKay |first=David |date=9 September 2022 |title=Exceeding 1.5°C global warming could trigger multiple climate tipping points – paper explainer |url=https://climatetippingpoints.info/2022/09/09/climate-tipping-points-reassessment-explainer/ |access-date=2 October 2022 |website=climatetippingpoints.info |language=en}}</ref>
The entire East Antarctic Ice Sheet holds enough ice to raise global sea levels by {{Convert|53.3|m|ft|abbr=on}}.<ref name="Fretwell2013" /> Its complete melting is also possible, but it would require very high warming and a lot of time:n 2022, an extensive assessment of [[tipping points in the climate system]] published in the [[Science Magazine]] concluded that the ice sheet would take a minimum of 10,000 years to fuly melt. It would most likely be committed to complete disappearance only once the global warming reaches about {{convert|7.5|C-change|F-change}}, with the minimum and the maximum range between {{convert|5|C-change|F-change}} and {{convert|10|C-change|F-change}}.<ref name="ArmstrongMcKay2022" /><ref name="ArmstrongMcKayExplainer" /> Another estimate suggested that at least {{convert|6|C-change|F-change}} would be needed to melt two thirds of its volume.<ref name="Garbe2020">{{Cite journal |last1=Garbe |first1=Julius |last2=Albrecht |first2=Torsten |last3=Levermann |first3=Anders |last4=Donges |first4=Jonathan F. |last5=Winkelmann |first5=Ricarda |date=2020 |title=The hysteresis of the Antarctic Ice Sheet |url=https://www.nature.com/articles/s41586-020-2727-5 |journal=Nature |volume=585 |issue=7826 |pages=538–544 |doi=10.1038/s41586-020-2727-5|pmid=32968257 |bibcode=2020Natur.585..538G |s2cid=221885420 }}</ref> It would also for the entire ice sheet to be lost.
If the ice sheet were to disappear, then the change in [[ice-albedo feedback]] would increase the global temperature by {{convert|0.6|C-change|F-change}}, while the regional temperatures would increase by around {{convert|2|C-change|F-change}}. The loss of the subglacial basins alone would only add about {{convert|0.05|C-change|F-change}} to global temperatures due to their relatively limited area, and a correspondingly low impact on global albedo.<ref name="ArmstrongMcKay2022">{{Cite journal |last1=Armstrong McKay |first1=David|last2=Abrams |first2=Jesse |last3=Winkelmann |first3=Ricarda |last4=Sakschewski |first4=Boris |last5=Loriani |first5=Sina |last6=Fetzer |first6=Ingo|last7=Cornell|first7=Sarah |last8=Rockström |first8=Johan |last9=Staal |first9=Arie |last10=Lenton |first10=Timothy |date=9 September 2022 |title=Exceeding 1.5°C global warming could trigger multiple climate tipping points |url=https://www.science.org/doi/10.1126/science.abn7950 |journal=Science |language=en |volume=377 |issue=6611 |doi=10.1126/science.abn7950 |hdl=10871/131584 |s2cid=252161375 |issn=0036-8075|hdl-access=free }}</ref><ref name="ArmstrongMcKayExplainer">{{Cite web |last=Armstrong McKay |first=David |date=9 September 2022 |title=Exceeding 1.5°C global warming could trigger multiple climate tipping points – paper explainer |url=https://climatetippingpoints.info/2022/09/09/climate-tipping-points-reassessment-explainer/ |access-date=2 October 2022 |website=climatetippingpoints.info |language=en}}</ref>


== See also ==
== See also ==

Revision as of 11:00, 2 February 2024

80°S 60°E / 80°S 60°E / -80; 60

East Antarctic ice sheet
TypeIce sheet
Thickness~2.2 km (1.4 mi) (average),[1] ~4.9 km (3.0 mi) (maximum) [2]

The East Antarctic Ice Sheet (EAIS) lies between 45° west and 168° east longitudinally. It was first formed around 34 million years ago,[3] and it is the largest ice sheet on the entire planet, with far greater volume than the Greenland ice sheet or the West Antarctic Ice Sheet (WAIS), from which it is separated by the Transantarctic Mountains. The ice sheet is around 2.2 km (1.4 mi) thick on average and is 4,897 m (16,066 ft) at its thickest point.[2] It is also home to the geographic South Pole and the Amundsen–Scott South Pole Station.

The surface of the EAIS is the driest, windiest, and coldest place on Earth. Lack of moisture in the air, high albedo from the snow as well as the surface's consistently high elevation[4] results in the reported cold temperature records of nearly −100 °C (212 °F).[5][6] It is the only place on Earth cold enough for atmospheric temperature inversion to occur consistently. That is, while the atmosphere is typically warmest near the surface and becomes cooler at greater elevation, atmosphere during the Antarctic winter is cooler at the surface than in its middle layers. Consequently, greenhouse gases actually trap heat in the middle atmosphere and reduce its flow towards the surface while the temperature inversion lasts.[4]

Due to these factors, East Antarctica had experienced slight cooling for decades while the rest of the world warmed as the result of climate change. Clear warming over East Antarctica only started to occur since the year 2000, and was not conclusively detected until the 2020s.[7][8] In the early 2000s, cooling over East Antarctica seemingly outweighing warming over the rest of the continent was frequently misinterpeted by the media and occasionally used as an argument for climate change denial.[9][10][11] After 2009, improvements in Antarctica's instrumental temperature record have proven that the warming over West Antarctica resulted in consistent net warming across the continent since the 1957.[12]

Because the East Antarctic ice sheet has barely warmed, it is still gaining ice on average.[13][14] for instance, GRACE satellite data indicated East Antarctica mass gain of 60 ± 13 billion tons per year between 2002 to 2010.[15] It is most likely to first see sustained losses of ice at its most vulnerable locations such as Totten Glacier and Wilkes Basin. Those areas are sometimes collectively described as East Antarctica's subglacial basins, and it is believed that once the warming reaches around 3 °C (5.4 °F), then they would start to collapse over a period of around 2,000 years,[16][17] This collapse would ultimately add between 1.4 m (4 ft 7 in) and 6.4 m (21 ft 0 in) to sea levels, depending on the ice sheet model used.[18] The EAIS as a whole holds enough ice to raise global sea levels by 53.3 m (175 ft).[2] However, it would take global warming in a range between 5 °C (9.0 °F) and 10 °C (18 °F), and a minimum of 10,000 years for the entire ice sheet to be lost.[16][17]

Description

Location and diagram of Lake Vostok, a prominent subglacial lake beneath the East Antarctic Ice Sheet.

East Antarctic Ice Sheet is located directly above the East Antarctic Shield - a craton (stable area of the Earth's crust) with the area of 10,200,000 km2 (3,900,000 sq mi), which accounts for around 73% of the entire Antarctic landmass.[19] East Antarctica is separate from West Antarctica due to the presence of Transantarctic Mountains, which span nearly 3,500 km (2,200 mi) from the Weddell Sea to the Ross Sea, and have a width of 100–300 km (62–186 mi).[1]

The ice sheet has an average thickness of around 2.2 km (1.4 mi). The thickest ice in Antarctica is located near Adelie Land close to the ice sheet's southeast coast, at the Astrolabe Subglacial Basin, where it measured 4,897 m (16,066 ft) around 2013.[1] Much of the ice sheet is already located at a high elevation: in particular, Dome Argus Plateau has an average height of around 4 km (2.5 mi), and yet it is underlain by the Gamburtsev Mountain Range, which has the average height of 2.7 km (1.7 mi) and is about equivalent in size to the European Alps.[20][21] Consequently, the ice thickness over these mountains ranges from around 1 km (0.62 mi) over their peaks to about 3 km (1.9 mi) over the valleys.[22]

South Pole research station.

These high elevations are an important reason for why the ice sheet is the driest, windiest, and coldest place on Earth. Dome A in particular sets reported cold temperature records of nearly −100 °C (212 °F).[5][6][4] The only ice-free areas of East Antarctica are where there is too little annual precipitation to form an ice layer, which is the case in the so-called McMurdo Dry Valleys of the Southern Victoria Land. Another exception are the subglacial lakes, which occur so deep beneath the ice that the pressure melting point is well below 0 °C (32 °F).[22]

Many countries have made territorial claims in Antarctica. Within EAIS, the United Kingdom, France, Norway, Australia, Chile and Argentina all claim a portion (sometimes overlapping) as their own territory.[23]

Geologic history

Polar climatic temperature changes throughout the Cenozoic, showing glaciation of Antarctica toward the end of the Eocene, thawing near the end of the Oligocene and subsequent Miocene re-glaciation.

While relatively small glaciers and ice caps are known to have been present in Antarctica since at least the time of Late Palaeocene, 60 million years ago,[24] a proper ice sheet did not begin to form until the Eocene–Oligocene extinction event about 34 million years ago, when the atmospheric CO2 levels fell to below 750 parts per million. It was initially unstable, and did not grow to consistently cover the entire continent until 32.8 million years ago, when the CO2 levels had further declined to below 600 ppm.[3]

Afterwards, the East Antarctic Ice Sheet declined substantially during the Middle Miocene Climatic Optimum 15 million years ago, yet started to recover about 13.96 million years ago.[24] Since then, it had been largely stable, experiencing "minimal" change in its surface extent over the past 8 million years.[25] While it had still thinned by at least 500 m (1,600 ft) during the Pleistocene period, and by less than 50 m (160 ft) since Last Glacial Maximum, the land area covered by ice in East Antarctica remained largely the same.[26] Contrastingly, the smaller West Antarctic ice sheet is thought to have largely collapsed as recently as during the Eemian period, about 125,000 years ago.[27][28][29][30][31]

Recent climate change

East Antarctica had demonstrated cooling in the 1980s and 1990s, even as the West Antarctica warmed (left-hand side). This trend had largely reversed in 2000s and 2010s (right-hand side).[32]

Antarctica as a whole has low sensitivity to climate change because it is surrounded by the Southern Ocean, which is more effective at absorbing heat than any other ocean due to the currents of the Southern Ocean overturning circulation,[33][34] and because of the high albedo (reflectivity) of its icy surface and of the surrounding sea ice.[4] These factors make Antarctica the coldest continent, and East Antarctica is additionally cooler than the West Antarctica, because it is located at a substantially greater elevation.[4] This makes it the only place on Earth cold enough for atmospheric temperature inversion to occur every winter.[4] While the atmosphere on Earth is at its warmest near the surface and becomes cooler as elevation increases, temperature inversion during the Antarctic winter results in middle layers of the atmosphere being warmer than the surface.[4] Thus, greenhouse gases trap heat in the middle atmosphere and reduce its flow towards the surface and towards space, while normally, they prevent the flow of heat from the lower atmosphere and towards. This effect lasts until the end of the Antarctic winter.[4]

Due to these factors, East Antarctica had experienced cooling in the 1980s and 1990s. For instance, between 1986 to 2006 there had been a cooling of 0.7 °C per decade at Lake Hoare station in the McMurdo Dry Valleys.[35] A 2002 paper by Peter Doran suggested that the cooling over East Antarctica outweighed warming of the rest of the continent.[36] While the paper estimated that about 42% of the Antarctic area had been warming, it was wrongly described by many media outlets as a proof that there was no warming in Antarctica.[9] In 2004, author Michael Crichton used that cooling as one of his arguments for denying climate change in his novel State of Fear.[37] First other scientists, and then Peter Doran himself eventually had to debunk the book's claims.[10][11] In 2009, it was demonstrated that the West Antarctic Ice Sheet has warmed by more than 0.1 °C/decade since the 1950s, resulting in a statistically significant warming trend across Antarctica of >0.05 °C/decade since 1957.[12] Later research found that after 2000, the warming of West Antarctica locations slowed or partially reversed between 2000 and 2020, while the East Antarctica interior had demonstated clear warming. This happened due to the local changes in Southern Annular Mode the dominant climate variability pattern over the Antarctica. Some of those changes were caused by the ozone layer beginning to recover following the Montreal Protocol.[7][8]

Aerial view of ice flows at Denman Glacier, one of the relatively few glaciers in the East Antarctica known to be losing mass.[38]

The limited warming and already low temperatures over East Antarctica mean that as of early 2020s, the majority of observational evidence shows it continuing to gain mass.[15][39][13][14] Some analyses have suggested it already began to lose mass in 2000s,[40][41] but they over-extrapolated some observed losses onto the poorly-observed areas, and a more complete observational record shows continued mass gain.[13]

If countries cut greenhouse gas emissions significantly (lowest trace), then sea level rise by 2100 can be limited to 0.3–0.6 m (1–2 ft).[42] If the emissions instead accelerate rapidly (top trace), sea levels could rise 5 m (16+12 ft) by the year 2300. Higher levels of sea level rise would involve ice loss from the East Antarctica.[42]

Because it is currently gaining mass, East Antarctic Ice Sheet is not expected to play a role in the 21st century sea level rise. However, it is still subject to adverse change, such as the retreat of Denman Glacier,[38][43] or the flow of warmer ocean current into ice cavities beneath the stabilizing ice shelves like the Fimbulisen ice shelf in the Queen Maud Land.[44] If global warming were to reach higher levels, then the EAIS would play an increasingly larger role in sea level rise occurring after 2100. According to the most recent reports of the Intergovernmental Panel on Climate Change (SROCC and the IPCC Sixth Assessment Report), the most intense climate change scenario, where the anthropogenic emissions increase continuously, RCP8.5, would result in Antarctica alone losing a median of 1.46 m (4 ft 9 in) (confidence interval between 60 cm (2.0 ft) and 2.89 m (9 ft 6 in)) by 2300, which would involve some loss from the EAIS in addition to the erosion of the WAIS. This Antarctica-only sea level rise would be in addition to ice losses from the Greenland ice sheet and mountain glaciers, as well as the thermal expansion of ocean water.[45]

Long-term future

Retreat of Cook Glacier - a key part of the Wilkes Basin - during the Eemian ~120,000 years ago and an earlier Pleistocene interglacial ~330,000 years ago. These retreats would have added about 0.5 m (1 ft 8 in) and 0.9 m (2 ft 11 in) to sea level rise.[46]

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. First, though, it would see sustained erosion at the so-called subglacial basins, such as Totten Glacier and Wilkes Basin, which are located in vulnerable locations below the sea level. Estimates suggest that they would be committed to disappearance once the global warming reaches 3 °C (5.4 °F), although the plausible temperature range is between 2 °C (3.6 °F) and 6 °C (11 °F). Once it becomes too warm for these subglacial basins, their collapse would unfold over a period of around 2,000 years, although it may be as fast as 500 years or as slow as 10,000 years.[16][17] The loss of all this ice would ultimately add between 1.4 m (4 ft 7 in) and 6.4 m (21 ft 0 in) to sea levels, depending on the ice sheet model used. Isostatic rebound of the newly ice-free land would also add 8 cm (3.1 in) and 57 cm (1 ft 10 in), respectively.[18] Evidence from the Pleistocene shows that partial loss can also occur at lower warming levels: Wilkes Basin is estimated to have lost enough ice to add 0.5 m (1 ft 8 in) to sea levels between 115,000 and 129,000 years ago, during the Eemian, and about 0.9 m (2 ft 11 in) between 318,000 and 339,000 years ago, during the Marine Isotope Stage 9.[46]

The entire East Antarctic Ice Sheet holds enough ice to raise global sea levels by 53.3 m (175 ft).[2] Its complete melting is also possible, but it would require very high warming and a lot of time:n 2022, an extensive assessment of tipping points in the climate system published in the Science Magazine concluded that the ice sheet would take a minimum of 10,000 years to fuly melt. It would most likely be committed to complete disappearance only once the global warming reaches about 7.5 °C (13.5 °F), with the minimum and the maximum range between 5 °C (9.0 °F) and 10 °C (18 °F).[16][17] Another estimate suggested that at least 6 °C (11 °F) would be needed to melt two thirds of its volume.[47] It would also for the entire ice sheet to be lost.

If the ice sheet were to disappear, then the change in ice-albedo feedback would increase the global temperature by 0.6 °C (1.1 °F), while the regional temperatures would increase by around 2 °C (3.6 °F). The loss of the subglacial basins alone would only add about 0.05 °C (0.090 °F) to global temperatures due to their relatively limited area, and a correspondingly low impact on global albedo.[16][17]

See also

References

  1. ^ a b c Torsvik, T. H.; Gaina, C.; Redfield, T. F. (2008). "Antarctica and Global Paleogeography: From Rodinia, Through Gondwanaland and Pangea, to the Birth of the Southern Ocean and the Opening of Gateways". Antarctica: A Keystone in a Changing World. pp. 125–140. doi:10.17226/12168. ISBN 978-0-309-11854-5.
  2. ^ a b c d Fretwell, P.; Pritchard, H. D.; Vaughan, D. G.; Bamber, J. L.; Barrand, N. E.; Bell, R.; Bianchi, C.; Bingham, R. G.; Blankenship, D. D. (2013-02-28). "Bedmap2: improved ice bed, surface and thickness datasets for Antarctica". The Cryosphere. 7 (1): 375–393. Bibcode:2013TCry....7..375F. doi:10.5194/tc-7-375-2013. hdl:1808/18763. ISSN 1994-0424.
  3. ^ a b Galeotti, Simone; DeConto, Robert; Naish, Timothy; Stocchi, Paolo; Florindo, Fabio; Pagani, Mark; Barrett, Peter; Bohaty, Steven M.; Lanci, Luca; Pollard, David; Sandroni, Sonia; Talarico, Franco M.; Zachos, James C. (10 March 2016). "Antarctic Ice Sheet variability across the Eocene-Oligocene boundary climate transition". Science. 352 (6281): 76–80. doi:10.1126/science.aab066.
  4. ^ a b c d e f g h Singh, Hansi A.; Polvani, Lorenzo M. (10 January 2020). "Low Antarctic continental climate sensitivity due to high ice sheet orography". npj Climate and Atmospheric Science. 3. doi:10.1038/s41612-020-00143-w. S2CID 222179485.
  5. ^ a b Scambos, T. A.; Campbell, G. G.; Pope, A.; Haran, T.; Muto, A.; Lazzara, M.; Reijmer, C. H.; Van Den Broeke, M. R. (25 June 2018). "Ultralow Surface Temperatures in East Antarctica From Satellite Thermal Infrared Mapping: The Coldest Places on Earth". Geophysical Research Letters. 45 (12): 6124–6133. Bibcode:2018GeoRL..45.6124S. doi:10.1029/2018GL078133. hdl:1874/367883.
  6. ^ a b Vizcarra, Natasha (25 June 2018). "New study explains Antarctica's coldest temperatures". National Snow and Ice Data Center. Retrieved 10 January 2024.
  7. ^ a b Xin, Meijiao; Clem, Kyle R; Turner, John; Stammerjohn, Sharon E; Zhu, Jiang; Cai, Wenju; Li, Xichen (2 June 2023). "West-warming East-cooling trend over Antarctica reversed since early 21st century driven by large-scale circulation variation". Environmental Research Letters. 18 (6): 064034. doi:10.1088/1748-9326/acd8d4.
  8. ^ a b Xin, Meijiao; Li, Xichen; Stammerjohn, Sharon E; Cai, Wenju; Zhu, Jiang; Turner, John; Clem, Kyle R; Song, Chentao; Wang, Wenzhu; Hou, Yurong (17 May 2023). "A broadscale shift in antarctic temperature trends". Climate Dynamics. 61: 4623–4641. doi:10.1007/s00382-023-06825-4.
  9. ^ a b Davidson, Keay (2002-02-04). "Media goofed on Antarctic data / Global warming interpretation irks scientists". San Francisco Chronicle. Retrieved 2013-04-13.
  10. ^ a b Eric Steig; Gavin Schmidt (2004-12-03). "Antarctic cooling, global warming?". Real Climate. Retrieved 2008-08-14. At first glance this seems to contradict the idea of "global" warming, but one needs to be careful before jumping to this conclusion. A rise in the global mean temperature does not imply universal warming. Dynamical effects (changes in the winds and ocean circulation) can have just as large an impact, locally as the radiative forcing from greenhouse gases. The temperature change in any particular region will in fact be a combination of radiation-related changes (through greenhouse gases, aerosols, ozone and the like) and dynamical effects. Since the winds tend to only move heat from one place to another, their impact will tend to cancel out in the global mean.
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