Ice sheet - Knowledge

386:. In that case, the ice sheet may not be thinning at all, as the amount of ice flowing over the grounding line would be likely to match the annual accumulation of ice from snow upstream. Otherwise, ocean warming at the base of an ice shelf tends to thin it through basal melting. As the ice shelf becomes thinner, it exerts less of a buttressing effect on the ice sheet, the so-called back stress increases and the grounding line is pushed backwards. The ice sheet is likely to start losing more ice from the new location of the grounding line and so become lighter and less capable of displacing seawater. This eventually pushes the grounding line back even further, creating a 1306: 1100: 484: ft) in basal (underground) height are likely to collapse under their own weight once the peripheral ice stabilizing them is gone. Their collapse then exposes the ice masses following them to the same instability, potentially resulting in a self-sustaining cycle of cliff collapse and rapid ice sheet retreat - i.e. sea level rise of a meter or more by 2100 from Antarctica alone. This theory had been highly influential - in a 2020 survey of 106 experts, the paper which had advanced this theory was considered more important than even the year 2014 38: 1386: 1444:, the northern hemisphere warmed considerably, dramatically increasing the release of methane from wetlands, that were otherwise tundra during glacial times. This methane quickly distributes evenly across the globe, becoming incorporated in Antarctic and Greenland ice. With this tie, paleoclimatologists have been able to say that the ice sheets on Greenland only began to warm after the Antarctic ice sheet had been warming for several thousand years. Why this pattern occurs is still open for debate. 732: 532: 170: 399: 1554: 1462: 9644: 214: 9632: 281: 9668: 9656: 427:

near future, although the dynamic behavior of Totten Ice Shelf is known to vary on seasonal to interannual timescales. The Wilkes Basin is the only major submarine basin in Antarctica that is not thought to be sensitive to warming. Ultimately, even geologically rapid sea level rise would still most likely require several millennia for the entirety of these ice masses (WAIS and the subglacial basins) to be lost.

939: 222: 268:. These lakes may feed warm water to glacial bases and facilitate glacial motion. Lakes of a diameter greater than ~300 m are capable of creating a fluid-filled crevasse to the glacier/bed interface. When these crevasses form, the entirety of the lake's (relatively warm) contents can reach the base of the glacier in as little as 2–18 hours – lubricating the bed and causing the glacier to 1065:. 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, 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 436: 5331:

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.

260:, an ice stream will remain almost stationary for hours at a time, before a surge of around a foot in under an hour, just after the peak high tide; a stationary period then takes hold until another surge towards the middle or end of the falling tide. At neap tides, this interaction is less pronounced, and surges instead occur approximately every 12 hours. 571:- did not resemble predictions from ice cliff collapse at least up until the end of 2013, but an event observed at Helheim Glacier in August 2014 may fit the definition. Further, modelling done after the initial hypothesis indicates that ice-cliff instability would require implausibly fast ice shelf collapse (i.e. within an hour for ~90 m ( 371:. Effectively, these marine ice sheets must have enough mass to exceed the mass of the seawater displaced by the ice, which requires excess thickness. As the ice sheet melts and becomes thinner, the weight of the overlying ice decreases. At a certain point, sea water could force itself into the gaps which form at the base of the ice sheet, and 7420:

Woodward, John; Winter, Kate; Weyrich, Laura S.; Rootes, Camilla M.; Millman, Helen; Albert, Paul G.; Rivera, Andres; Ommen, Tas van; Curran, Mark; Moy, Andrew; Rahmstorf, Stefan; Kawamura, Kenji; Hillenbrand, Claus-Dieter; Weber, Michael E.; Manning, Christina J.; Young, Jennifer; Cooper, Alan (25 February 2020).

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Briner, Jason P.; Cuzzone, Joshua K.; Badgeley, Jessica A.; Young, Nicolás E.; Steig, Eric J.; Morlighem, Mathieu; Schlegel, Nicole-Jeanne; Hakim, Gregory J.; Schaefer, Joerg M.; Johnson, Jesse V.; Lesnek, Alia J.; Thomas, Elizabeth K.; Allan, Estelle; Bennike, Ole; Cluett, Allison A.; Csatho, Beata;

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is an ice sheet which forms the second largest body of ice in the world. It is an average of 1.67 km (1.0 mi) thick, and over 3 km (1.9 mi) thick at its maximum. It is almost 2,900 kilometres (1,800 mi) long in a north–south direction, with a maximum width of 1,100 kilometres

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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

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Christ, Andrew J.; Bierman, Paul R.; Schaefer, Joerg M.; Dahl-Jensen, Dorthe; Steffensen, Jørgen P.; Corbett, Lee B.; Peteet, Dorothy M.; Thomas, Elizabeth K.; Steig, Eric J.; Rittenour, Tammy M.; Tison, Jean-Louis; Blard, Pierre-Henri; Perdrial, Nicolas; Dethier, David P.; Lini, Andrea; Hidy, Alan

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could stabilize them, but it would be extraordinarily difficult and may not account for the ongoing acceleration of ocean warming in the area. Others suggest that building obstacles to warm water flows beneath glaciers would be able to delay the disappearance of the ice sheet by many centuries, but

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period, when the global temperatures were similar to the early 21st century. It is believed that the loss of the ice sheet would take place between 2,000 and 13,000 years in the future, although several centuries of high emissions may shorten this to 500 years. 3.3 m (10 ft 10 in) of

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is the largest glacier there which is known to be subject to MISI - yet, its potential contribution to sea level rise is comparable to that of the entire West Antarctic Ice Sheet. Totten Glacier has been losing mass nearly monotonically in recent decades, suggesting rapid retreat is possible in the

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Even stable ice sheets are continually in motion as the ice gradually flows outward from the central plateau, which is the tallest point of the ice sheet, and towards the margins. The ice sheet slope is low around the plateau but increases steeply at the margins. This difference in slope occurs due

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If all 2,900,000 cubic kilometres (696,000 cu mi) of the ice sheet were to melt, it would increase global sea levels by ~7.4 m (24 ft). Global warming between 1.7 °C (3.1 °F) and 2.3 °C (4.1 °F) would likely make this melting inevitable. However, 1.5 °C

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have a much greater area than this minimum definition, measuring at 1.7 million km and 14 million km, respectively. Both ice sheets are also very thick, as they consist of a continuous ice layer with an average thickness of 2 km (1 mi). This ice layer forms because most of the snow which

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are abrupt warmings of the northern hemisphere occurring over the space of perhaps 40 years. While these D–O events occur directly after each Heinrich event, they also occur more frequently – around every 1500 years; from this evidence, paleoclimatologists surmise that the same forcings may drive

6729:

Christ, Andrew J.; Rittenour, Tammy M.; Bierman, Paul R.; Keisling, Benjamin A.; Knutz, Paul C.; Thomsen, Tonny B.; Keulen, Nynke; Fosdick, Julie C.; Hemming, Sidney R.; Tison, Jean-Louis; Blard, Pierre-Henri; Steffensen, Jørgen P.; Caffee, Marc W.; Corbett, Lee B.; Dahl-Jensen, Dorthe; Dethier,

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The collapse of the Larsen B shelf was preceded by thinning of just 1 metre per year, while some other Antarctic ice shelves have displayed thinning of tens of metres per year. Further, increased ocean temperatures of 1 °C may lead to up to 10 metres per year of basal melting. Ice

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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

5015:

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

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Turney, Chris S. M.; Fogwill, Christopher J.; Golledge, Nicholas R.; McKay, Nicholas P.; Sebille, Erik van; Jones, Richard T.; Etheridge, David; Rubino, Mauro; Thornton, David P.; Davies, Siwan M.; Ramsey, Christopher Bronk; Thomas, Zoë A.; Bird, Michael I.; Munksgaard, Niels C.; Kohno, Mika;

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There is a massive contrast in carbon storage between the two ice sheets. While only about 0.5-27 billion tonnes of pure carbon are present underneath the Greenland ice sheet, 6000-21,000 billion tonnes of pure carbon are thought to be located underneath Antarctica. This carbon can act as a

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Lau, Sally C. Y.; Wilson, Nerida G.; Golledge, Nicholas R.; Naish, Tim R.; Watts, Phillip C.; Silva, Catarina N. S.; Cooke, Ira R.; Allcock, A. Louise; Mark, Felix C.; Linse, Katrin (21 December 2023). "Genomic evidence for West Antarctic Ice Sheet collapse during the Last Interglacial".

1296: ft) of sea level rise, and more ice will be lost if the temperatures exceed that level before declining. If global temperatures continue to rise, the ice sheet will likely disappear within 10,000 years. At very high warming, its future lifetime goes down to around 1,000 years. 226: 3295:

Horton, Benjamin P.; Khan, Nicole S.; Cahill, Niamh; Lee, Janice S. H.; Shaw, Timothy A.; Garner, Andra J.; Kemp, Andrew C.; Engelhart, Simon E.; Rahmstorf, Stefan (2020-05-08). "Estimating global mean sea-level rise and its uncertainties by 2100 and 2300 from an expert survey".

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Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022). "Exceeding 1.5 °C global warming could trigger multiple climate tipping points".

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from the snow as well as the surface's consistently high elevation results in the reported cold temperature records of nearly −100 °C (−148 °F). It is the only place on Earth cold enough for atmospheric temperature inversion to occur consistently. That is, while the

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but is controlled by temperature and the strength of individual glacier bases. A number of processes alter these two factors, resulting in cyclic surges of activity interspersed with longer periods of inactivity, on time scales ranging from hourly (i.e. tidal flows) to the

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The preservation of WAIS may require a persistent reduction of global temperatures to 1 °C (1.8 °F) below the preindustrial level, or to 2 °C (3.6 °F) below the temperature of 2020. Because the collapse of the ice sheet would be preceded by the loss of

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used. The EAIS as a whole holds enough ice to raise global sea levels by 53.3 m (175 ft). 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

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Edwards, Tamsin L.; Brandon, Mark A.; Durand, Gael; Edwards, Neil R.; Golledge, Nicholas R.; Holden, Philip B.; Nias, Isabel J.; Payne, Antony J.; Ritz, Catherine; Wernecke, Andreas (6 February 2019). "Revisiting Antarctic ice loss due to marine ice-cliff instability".

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Pan, Linda; Powell, Evelyn M.; Latychev, Konstantin; Mitrovica, Jerry X.; Creveling, Jessica R.; Gomez, Natalya; Hoggard, Mark J.; Clark, Peter U. (30 April 2021). "Rapid postglacial rebound amplifies global sea level rise following West Antarctic Ice Sheet collapse".

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Young, Duncan A.; Wright, Andrew P.; Roberts, Jason L.; Warner, Roland C.; Young, Neal W.; Greenbaum, Jamin S.; Schroeder, Dustin M.; Holt, John W.; Sugden, David E. (2011-06-02). "A dynamic early East Antarctic Ice Sheet suggested by ice-covered fjord landscapes".

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Bond, Gerard C.; Showers, William; Elliot, Mary; Evans, Michael; Lotti, Rusty; Hajdas, Irka; Bonani, Georges; Johnson, Sigfus (1999). "The North Atlantic's 1–2 kyr climate rhythm: Relation to Heinrich events, Dansgaard/Oeschger cycles and the Little Ice Age".

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for at least 18 million years, but a single ice sheet first covered most of the island some 2.6 million years ago. Since then, it has both grown and contracted significantly. The oldest known ice on Greenland is about 1 million years old. Due to anthropogenic

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sea level rise would occur if the ice sheet collapses but leaves ice caps on the mountains behind. Total sea level rise from West Antarctica increases to 4.3 m (14 ft 1 in) if they melt as well, but this would require a higher level of warming.

4291:; Xiao, C.; Aðalgeirsdóttir, G.; Drijfhout, S. S.; Edwards, T. L.; Golledge, N. R.; Hemer, M.; Kopp, R. E.; Krinner, G.; Mix, A. (2021). Masson-Delmotte, V.; Zhai, P.; Pirani, A.; Connors, S. L.; Péan, C.; Berger, S.; Caud, N.; Chen, Y.; Goldfarb, L. (eds.). 3906:

Barnett, Robert L.; Austermann, Jacqueline; Dyer, Blake; Telfer, Matt W.; Barlow, Natasha L. M.; Boulton, Sarah J.; Carr, Andrew S.; Creel, Roger (15 September 2023). "Constraining the contribution of the Antarctic Ice Sheet to Last Interglacial sea level".

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Bell, R. E.; Ferraccioli, F.; Creyts, T. T.; Braaten, D.; Corr, H.; Das, I.; Damaske, D.; Frearson, N.; Jordan, T.; Rose, K.; Studinger, M.; Wolovick, M. (2011). "Widespread Persistent Thickening of the East Antarctic Ice Sheet by Freezing from the Base".

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A reconstruction of how Heinrich events would have likely proceeded, with the Laurentide ice sheet first growing to an unsustainable position, where the base of its periphery becomes too warm, and then rapidly losing ice until it is reduced to sustainable

1031:. Clear warming over East Antarctica only started to occur since the year 2000, and was not conclusively detected until the 2020s. In the early 2000s, cooling over East Antarctica seemingly outweighing warming over the rest of the continent was frequently 6542:; Xiao, C.; Aðalgeirsdóttir, G.; Drijfhout, S.S.; Edwards, T.L.; Golledge, N.R.; Hemer, M.; Kopp, R.E.; Krinner, G.; Mix, A. (2021). Masson-Delmotte, V.; Zhai, P.; Pirani, A.; Connors, S.L.; Péan, C.; Berger, S.; Caud, N.; Chen, Y.; Goldfarb, L. (eds.). 2750:; Xiao, C.; Aðalgeirsdóttir, G.; Drijfhout, S.S.; Edwards, T.L.; Golledge, N.R.; Hemer, M.; Kopp, R.E.; Krinner, G.; Mix, A. (2021). Masson-Delmotte, V.; Zhai, P.; Pirani, A.; Connors, S.L.; Péan, C.; Berger, S.; Caud, N.; Chen, Y.; Goldfarb, L. (eds.). 418:

glaciers are most likely to be prone to MISI, and both glaciers have been rapidly thinning and accelerating in recent decades. As the result, sea level rise from the ice sheet could be accelerated by tens of centimeters within the 21st century alone.

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Japsen, Peter; Green, Paul F.; Bonow, Johan M.; Nielsen, Troels F.D.; Chalmers, James A. (5 February 2014). "From volcanic plains to glaciated peaks: Burial, uplift and exhumation history of southern East Greenland after opening of the NE Atlantic".

225: 1402:(the amount of sunlight reaching the Earth). These patterns are caused by the variations in shape of the Earth's orbit and its angle relative to the Sun, caused by the gravitational pull of other planets as they go through their own orbits. 523:

period which appears consistent with MICI. However, it indicates "relatively rapid" yet still prolonged ice sheet retreat, with a movement of >200 km (120 mi) inland taking place over an estimated 1100 years (from ~12,300 years

1577:, which cover 76,000 and 100,000 square kilometres (29,000 and 39,000 sq mi) around the periphery. Conditions in Greenland were not initially suitable for a single coherent ice sheet to develop, but this began to change around 10 1619:, allowing ice to accumulate and persist. As recently as 3 million years ago, during the Pliocene warm period, Greenland's ice was limited to the highest peaks in the east and the south. Ice cover gradually expanded since then, until the 1268:

by the end of the century. If there are no reductions in emissions, melting would add around 13 cm (5 in) by 2100, with a worst-case of about 33 cm (13 in). For comparison, melting has so far contributed 1.4 cm

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Increasing global air temperatures due to climate change take around 10,000 years to directly propagate through the ice before they influence bed temperatures, but may have an effect through increased surface melting, producing more

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Internal ice sheet "binge-purge" cycles may be responsible for the observed effects, where the ice builds to unstable levels, then a portion of the ice sheet collapses. External factors might also play a role in forcing ice sheets.

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Crawford, Anna J.; Benn, Douglas I.; Todd, Joe; Åström, Jan A.; Bassis, Jeremy N.; Zwinger, Thomas (11 May 2021). "Marine ice-cliff instability modeling shows mixed-mode ice-cliff failure and yields calving rate parameterization".

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Reyes, Alberto V.; Carlson, Anders E.; Beard, Brian L.; Hatfield, Robert G.; Stoner, Joseph S.; Winsor, Kelsey; Welke, Bethany; Ullman, David J. (25 June 2014). "South Greenland ice-sheet collapse during Marine Isotope Stage 11".

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Gilford, Daniel M.; Ashe, Erica L.; DeConto, Robert M.; Kopp, Robert E.; Pollard, David; Rovere, Alessio (5 October 2020). "Could the Last Interglacial Constrain Projections of Future Antarctic Ice Mass Loss and Sea-Level Rise?".

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Thiede, Jörn; Jessen, Catherine; Knutz, Paul; Kuijpers, Antoon; Mikkelsen, Naja; Nørgaard-Pedersen, Niels; Spielhagen, Robert F (2011). "Millions of Years of Greenland Ice Sheet History Recorded in Ocean Sediments".

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Höning, Dennis; Willeit, Matteo; Calov, Reinhard; Klemann, Volker; Bagge, Meike; Ganopolski, Andrey (27 March 2023). "Multistability and Transient Response of the Greenland Ice Sheet to Anthropogenic CO2 Emissions".

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Some scientists - including the originators of the hypothesis, Robert DeConto and David Pollard - have suggested that the best way to resolve the question would be to precisely determine sea level rise during the

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Hörhold, M.; Münch, T.; Weißbach, S.; Kipfstuhl, S.; Freitag, J.; Sasgen, I.; Lohmann, G.; Vinther, B.; Laepple, T. (18 January 2023). "Modern temperatures in central–north Greenland warmest in past millennium".

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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".

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Dumitru, Oana A.; Dyer, Blake; Austermann, Jacqueline; Sandstrom, Michael R.; Goldstein, Steven L.; D'Andrea, William J.; Cashman, Miranda; Creel, Roger; Bolge, Louise; Raymo, Maureen E. (15 September 2023).

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Hein, Andrew S.; Woodward, John; Marrero, Shasta M.; Dunning, Stuart A.; Steig, Eric J.; Freeman, Stewart P. H. T.; Stuart, Finlay M.; Winter, Kate; Westoby, Matthew J.; Sugden, David E. (3 February 2016).

611: ft). As of 2023, the most recent analysis indicates that the Last Interglacial SLR is unlikely to have been higher than 2.7 m (9 ft), as higher values in other research, such as 5.7 m ( 347:

shelves are always stable under mean annual temperatures of −9 °C, but never stable above −5 °C; this places regional warming of 1.5 °C, as preceded the collapse of Larsen B, in context.

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On an unrelated hour-to-hour basis, surges of ice motion can be modulated by tidal activity. The influence of a 1 m tidal oscillation can be felt as much as 100 km from the sea. During larger

832:. There has been warming over the ice sheet since the 1950s, and a substantial retreat of its coastal glaciers since at least the 1990s. Estimates suggest it added around 7.6 ± 3.9 mm ( 312:

icebergs at their periphery if they experience excess of ice. Ice shelves would also experience accelerated calving due to basal melting. In Antarctica, this is driven by heat fed to the shelf by the

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between 1992 and 2017, and has been losing ice in the 2010s at a rate equivalent to 0.4 millimetres (0.016 inches) of annual sea level rise. While some of its losses are offset by the growth of the

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Barr, Iestyn D.; Spagnolo, Matteo; Rea, Brice R.; Bingham, Robert G.; Oien, Rachel P.; Adamson, Kathryn; Ely, Jeremy C.; Mullan, Donal J.; Pellitero, Ramón; Tomkins, Matt D. (21 September 2022).

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Even if the ice sheet is grounded below the sea level, MISI cannot occur as long as there is a stable ice shelf in front of it. The boundary between the ice sheet and the ice shelf, known as the

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Koenig, S. J.; Dolan, A. M.; de Boer, B.; Stone, E. J.; Hill, D. J.; DeConto, R. M.; Abe-Ouchi, A.; Lunt, D. J.; Pollard, D.; Quiquet, A.; Saito, F.; Savage, J.; van de Wal, R. (5 March 2015).

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Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022).

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Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022).

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Armstrong McKay, David; Abrams, Jesse; Winkelmann, Ricarda; Sakschewski, Boris; Loriani, Sina; Fetzer, Ingo; Cornell, Sarah; Rockström, Johan; Staal, Arie; Lenton, Timothy (9 September 2022).

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broke apart sending large flotillas of icebergs into the North Atlantic. When these icebergs melted they dropped the boulders and other continental rocks they carried, leaving layers known as

224: 5838:

Noël, B.; van Kampenhout, L.; Lenaerts, J. T. M.; van de Berg, W. J.; van den Broeke, M. R. (19 January 2021). "A 21st Century Warming Threshold for Sustained Greenland Ice Sheet Mass Loss".

585: ft)-tall cliffs), unless the ice had already been substantially damaged beforehand. Further, ice cliff breakdown would produce a large number of debris in the coastal waters - known as 6730:

David P.; Hidy, Alan J.; Perdrial, Nicolas; Peteet, Dorothy M.; Steig, Eric J.; Thomas, Elizabeth K. (20 July 2023). "Deglaciation of northwestern Greenland during Marine Isotope Stage 11".

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Dow, Christine F.; Lee, Won Sang; Greenbaum, Jamin S.; Greene, Chad A.; Blankenship, Donald D.; Poinar, Kristin; Forrest, Alexander L.; Young, Duncan A.; Zappa, Christopher J. (2018-06-01).

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Dieser, Markus; Broemsen, Erik L J E; Cameron, Karen A; King, Gary M; Achberger, Amanda; Choquette, Kyla; Hagedorn, Birgit; Sletten, Ron; Junge, Karen; Christner, Brent C (17 April 2014).

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Li, Qian; England, Matthew H.; Hogg, Andrew McC.; Rintoul, Stephen R.; Morrison, Adele K. (29 March 2023). "Abyssal ocean overturning slowdown and warming driven by Antarctic meltwater".

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heat. In places, melting occurs and the melt-water lubricates the ice sheet so that it flows more rapidly. This process produces fast-flowing channels in the ice sheet — these are

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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,

539:(viewed from the top) would do a lot to determine how quickly it may proceed. Bays which are deep or narrow towards the exit would experience much less rapid retreat than the opposite 1311:

Estimated carbon fluxes are measured in Tg C a (megatonnes of carbon per year) and estimated sizes of carbon stores are measured in Pg C (thousands of megatonnes of carbon). DOC =

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Silvano, Alessandro; Rintoul, Stephen Rich; Peña-Molino, Beatriz; Hobbs, William Richard; van Wijk, Esmee; Aoki, Shigeru; Tamura, Takeshi; Williams, Guy Darvall (18 April 2018).

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Roberts, Jason; Galton-Fenzi, Benjamin K.; Paolo, Fernando S.; Donnelly, Claire; Gwyther, David E.; Padman, Laurie; Young, Duncan; Warner, Roland; Greenbaum, Jamin (2017-08-23).

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on a glacier until it begins to flow. The flow velocity and deformation will increase as the equilibrium line between these two processes is approached. This motion is driven by

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Solgaard, Anne M.; Bonow, Johan M.; Langen, Peter L.; Japsen, Peter; Hvidberg, Christine (27 September 2013). "Mountain building and the initiation of the Greenland Ice Sheet".

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Crémière, Antoine; Lepland, Aivo; Chand, Shyam; Sahy, Diana; Condon, Daniel J.; Noble, Stephen R.; Martma, Tõnu; Thorsnes, Terje; Sauer, Simone; Brunstad, Harald (11 May 2016).

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Mouginot, Jérémie; Rignot, Eric; Bjørk, Anders A.; van den Broeke, Michiel; Millan, Romain; Morlighem, Mathieu; Noël, Brice; Scheuchl, Bernd; Wood, Michael (20 March 2019).

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de Vernal, Anne; Downs, Jacob; Larour, Eric; Nowicki, Sophie (30 September 2020). "Rate of mass loss from the Greenland Ice Sheet will exceed Holocene values this century".

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King, M. A.; Bingham, R. J.; Moore, P.; Whitehouse, P. L.; Bentley, M. J.; Milne, G. A. (2012). "Lower satellite-gravimetry estimates of Antarctic sea-level contribution".

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Because the entire West Antarctic Ice Sheet is grounded below the sea level, it would be vulnerable to geologically rapid ice loss in this scenario. In particular, the

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Bassis, J. N.; Berg, B.; Crawford, A. J.; Benn, D. I. (18 June 2021). "Transition to marine ice cliff instability controlled by ice thickness gradients and velocity".

669:, with an area of 14 million square kilometres (5.4 million square miles) and an average thickness of over 2 kilometres (1.2 mi). It is the largest of 9544: 1832: 499:

could have occurred - yet more recent research found that these sea level rise episodes can be explained without any ice cliff instability taking place. Research in

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crashed in Greenland in 1942. It was only recovered 50 years later. By then, it had been buried under 81 m (268 feet) of ice which had formed over that time period.

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Aschwanden, Andy; Fahnestock, Mark A.; Truffer, Martin; Brinkerhoff, Douglas J.; Hock, Regine; Khroulev, Constantine; Mottram, Ruth; Khan, S. Abbas (19 June 2019).

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Pan, Linda; Powell, Evelyn M.; Latychev, Konstantin; Mitrovica, Jerry X.; Creveling, Jessica R.; Gomez, Natalya; Hoggard, Mark J.; Clark, Peter U. (30 April 2021).

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Diester-Haass, Liselotte; Zahn, Rainer (1996). "Eocene-Oligocene transition in the Southern Ocean: History of water mass circulation and biological productivity".

996:. 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. It is also home to the geographic 3677:

Parizek, Byron R.; Christianson, Knut; Alley, Richard B.; Voytenko, Denis; Vaňková, Irena; Dixon, Timothy H.; Walker, Ryan T.; Holland, David M. (22 March 2019).

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Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change

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