Consequences of global warming in Antarctica

from Wikipedia, the free encyclopedia
Satellite image
Ocean currents around the Antarctic

The consequences of global warming in Antarctica differ in many ways from those in other climatic zones on earth, and sometimes unexpected effects occur. In contrast to all other major regions of the world, Antarctica hardly warmed up overall in the 19th and 20th centuries. For periods from the 1970s to the second half of the 2010s, parts of West Antarctica warmed up; there was no significant change in the near-surface air temperature in East Antarctica. The Southern Ocean absorbs a considerable part of the additional heat, the sea temperatures around the Antarctic rise significantly.

Specifics of Antarctica in relation to global warming

Antarctica is a continent surrounded by oceans , unlike the Arctic , which is an ocean surrounded by continents . Water has a very high heat capacity and therefore heats up more slowly than rock and considerably more slowly than air; a layer of the first three meters of water in the world's oceans has a greater heat capacity than the entire earth's atmosphere.

The mixing of the oceans is different in the northern hemisphere than in the southern hemisphere. In the Arctic Ocean around Greenland, warm surface water sinks, while the Antarctic waters are characterized by the rise of cold deep water.

The Antarctic circumpolar current, which is responsible for icing the Antarctic, is used to continuously transport energy (approx. 140 million m³ of water per second).

Since the Antarctic katabatic winds are offshore winds, it is difficult for heated air masses from neighboring regions to reach the Antarctic mainland. The Antarctic continent is the highest continent in the world at an average of 2500 m and for this reason it is considerably colder than the Arctic at an average of −55 ° C. Therefore, no complete melting of the land ice masses is to be expected, even with strong warming. While the Arctic was last completely free of ice 3 million years ago, the Antarctic was last free of ice over 35 million years ago. In the event that the concentration of greenhouse gases continues to rise and the ban on CFCs reduces the ozone hole in the future, it is assumed that the Antarctic will continue to warm.

The thickness of the ice masses located on land areas in the Antarctic is up to 5 kilometers, the ice thickness of the Arctic, which consists of sea ice with the exception of the Greenland ice, is between several centimeters and a maximum of 5 meters.

As correctly predicted by climate models , there is significantly less warming in the southern hemisphere than in the northern hemisphere. A climate model that simulated the influence of global warming on sea ice cover over a period of 100 years showed a decrease of 60% in the Arctic, but only by 10% in the Antarctic.

Temperature development

Development of surface temperature in the Antarctic between 1957 and 2006 according to data from NASA. The warming, which is particularly evident in West Antarctica, is in contrast to an only slight increase in temperature in the eastern part.

An early climate model predicted a slight cooling of the Antarctic Ocean, followed by a warming, over a simulation course of 50 years. In 2007 this cooling could be found by measurement. However, in 2011 the significant and widespread warming predominated. The temperature development is not the same in all regions of the Antarctic. In West Antarctica, the temperature of the seawater rose sharply between 1960 and 2014, which probably had a significant influence on the glacier melt observed there.

The knowledge about the development of the temperature in the Antarctic is afflicted with some uncertainties, which result mainly from the low density of measuring stations and their relatively late commissioning. During the 19th and 20th centuries, Antarctica only warmed by an estimated 0.2 ° C. According to an analysis published in 2009 that calculates the temperature change since 1957, the western part of Antarctica has warmed considerably and the eastern part to a lesser extent (see picture on the right).

The West Antarctic Peninsula is the region that has heated up the most since the 1950s. At the level of the Vernadski station , the increase during this period was 0.56 ° C per decade as an annual mean, and even 1.09 ° C during the winter months. The interior of the continent, on the other hand, cooled down, especially during autumn. The development on the coasts was changeable, sometimes there was a slight cooling or warming or no change.

During the second half of the 20th century, the following temperature trends could be found averaged over the area from 60th to 90th parallel: Winter temperatures rose by 0.776 ° C, which, in accordance with the theory of the greenhouse effect, marks the greatest increase. Spring temperatures rose by 0.405 ° C; the smallest differences were found in the summer and autumn temperatures, which only rose by 0.193 ° C and 0.179 ° C, respectively. It was also discovered that the statistically significant warming is limited to the Antarctic Peninsula and a small region on the east coast of the continent. Temperature trends for the rest of the continent were not statistically significant.

The only slight warming since 1957 and the slight cooling since the late 1960s to the present day over the Antarctic continental shelf is currently attributed to two factors, namely increasing winds around the Antarctic and the ozone hole . Its extension over Antarctica reached a new record in 2006 with an area of ​​27.45 million square kilometers. Radiation absorption by ozone is the cause of the warming of the stratosphere , so that the ozone hole has led to a cooling of the stratosphere. The second reason is the strengthening of the south westerly wind zone , which moved closer to the South Pole. Due to the increase in the flow velocity, the air pressure within the ring fell - i.e. in the Antarctic, which led to an adiabatic cooling of the Antarctic.

Ice mass

Between 1992 and 2017 the Antarctic ice sheet increasingly lost mass (blue line), and all regions have been losing ice since 2012.

The first complete gravity analysis over the entire Antarctic ice sheet showed that in the observation period between April 2002 and August 2005 the average annual loss of ice mass was 152 (± 80) km³. The mass loss is practically entirely due to the West Antarctic ice sheet, which decreased by 148 ± 21 km³ annually, whereas the eastern Antarctic showed no clear trend (0 ± 56 km³). The measurements are still uncertain due to the short period of time and the methods. Between 1992 and 2003, according to another study, which included almost three quarters of the continent, there was an increase in ice mass of over 27 ± 29 km³ in the Antarctic. In 2007, the state of research was summarized with the rough estimate that West Antarctica is currently losing about 50 km³ of mass, while the eastern part is gaining roughly 25 km³.

There is considerable variability in precipitation, but no clear trend. If the entire continent is considered, there has been no permanent and significant change in snowfall at least since the 1950s. Between 1985 and 1994 the amount of precipitation increased, particularly in the interior of the Antarctic, while it had decreased in some areas in the coastal areas. This trend was then practically exactly reversed, so that between 1995 and 2004, apart from three exposed regions, less snow fell almost everywhere, in places up to 25%. In a study published in 2007, NASA researchers reported that areas in which melting can be observed have increasingly extended both further inland and at greater heights over the past 20 years.

A 2011 study looked at mass loss in the Arctic and Antarctic and found that between 1992 and 2009, Antarctica melted 14.5 gigatons more ice each year than the year before. According to an analysis by the Alfred Wegener Institute from 2014, 128 km³ annually melted in the Antarctic between 2011 and 2014. While there was ice growth in Dronning Maud Land in East Antarctica, the ice mass in West Antarctica decreased significantly, with ice loss there tripling in relation to the reference period 2003–2009. A study from 2014 came to a similar conclusion, in which the ice melt in West Antarctica between 1992 and 2014 was examined using 4 different methods. The authors conclude that 6.4 gigatons more ice was lost there alone than in the previous year. Over the past 21 years, an amount of ice equivalent to the weight of Mount Everest has melted there every two years . According to a study published in 2018, the Antarctic ice sheet lost around 183 billion tons of ice per year between 2008 and 2015, and the trend is rising.

glacier

The global melting of glaciers also takes place in the Antarctic. The Pine Island Glacier in western Antarctica, which flows into the Amundsen Sea , thinned 3.5 ± 0.9 m per year from 1992 to 1996 and has retreated about 5 km over the same period. A decline can also be observed on the Dakshin-Gangotri Glacier : Between 1983 and 2002 it retreated an average of 0.7 m per year. On the Antarctic Peninsula , the only part of Antarctica that protrudes beyond the Arctic Circle, there are hundreds of receding glaciers. A study examined 244 glaciers on the peninsula. 212 or 87% of the glaciers receded, averaging a total of 600 m from 1953 to 2003. The Sjogren Glacier has retreated the most with about 13 km since 1953. 32 of the examined glaciers grew. The average growth was 300 m per glacier, which is significantly less than the observed decline.

At the Thwaites glacier it is assumed that a so-called tipping point has been reached. It will melt over a period of 200–900 years.

Sea ice and ice shelves

The development of the September maximum up to and including 2017 ...
... and the minimum up to and including March 2017 indicate the slight increase in the Antarctic sea ice in summer.

While there was a clear loss of the area covered by sea ​​ice in the 1970s , this has increased again in recent years. In addition, the geographical distribution has also changed. While sea ice cover decreased in West Antarctica, it increased in East Antarctica, with the magnitude of the increase and decrease far exceeding the magnitude of the overall trend. However, scientists found in 2007 that the loss of mainland ice marginally exceeded its increase.

The northern regions of the West Antarctic Peninsula experience the greatest warming in the region, which led to the collapse of the Larsen B shelf in 2002 . The entire Larsen Ice Shelf consists of three individual shelves that cover various areas on the coast. These are called Larsen A, Larsen B and Larsen C (from north to south). Larsen A is the smallest and Larsen C is the largest of the shelves. Larsen A had already disbanded in January 1995, Larsen C is apparently stable at the moment. The dissolution of the Larsen B Shelf was determined between January 31 and March 7, 2002, when it finally broke off with an ice sheet of 3,250 square kilometers. Up until then, Larsen B was stable for over 10,000 years throughout the Holocene . In contrast, the Larsen A Shelf had only existed for 4,000 years. As a result, the land ice behind the shelf is now accelerating into the sea.

In 1993, Prof. David Vaughan of the British Antarctic Survey (BAS) said that the northern part of the Wilkins Shield is likely to melt within the next 30 years if the Antarctic Peninsula's temperature rise continues at the same rate. In the period between February and July 2008 the ice shelf broke open on a large scale and Prof. Vaughan corrected his prediction: his estimate was too conservative, the events happened faster than he had expected. Based on the pictures taken on July 7, 2008, Dr. Matthias Braun from the Center for Remote Sensing of Land Surfaces at the University of Bonn stated that the ice surface affected by the demolition was 1350 km² in size, which is about half the area of ​​the Grand Duchy of Luxembourg .

Collapse of the West Antarctic Ice Sheet

In 1974 J. Weertmann pointed out that ice sheets react very sensitively to global warming, as this can change their grounding line in such a way that the associated loss of stability leads to a dynamic loss of ice. John Mercer recognized in 1978 that the topology of the West Antarctic Ice Sheet represents the part of Antarctica that would be most likely to be threatened by such a collapse if global warming, which was already emerging at the time, continued, and he emphasized the disastrous consequences of this event if it should occur. In the years that followed, the West Antarctic ice sheet was intensively researched and a number of other publications supported the warnings from Weertmann and Mercer.

In 2014, several independent publications stated that the West Antarctic ice sheet could have crossed the limit for an irreversible collapse: in the next 100 to 300 years, an ice sheet the size of France will collapse, causing the sea level to rise by at least one meter becomes. In addition, studies have shown that the East Antarctic ice sheet will also be affected by disintegration.

In a study from 2016, the authors use a new model. This takes into account the disintegration of glaciers caused by warming, which end in the sea, lie there and form an ice sheet. By calibrating this model on the basis of climatic data from the Pliocene and the last interglacial, it provides a sea level rise of over one meter by the end of this century and of 15 meters by the year 2500, caused solely by the West Antarctic ice sheet.

One consequence of the ice loss is the uplift of the underlying land mass. This process can be traced back to an isostatic balance : In the asthenosphere , material flows under the area relieved of the melted ice mass and lifts the land there. Measurements at six GPS stations around the Amundsen Sea showed that the ground there rises unexpectedly quickly, by 41 mm per year. The reason is probably a relatively low viscosity of the earth's mantle below this region. If the warming is limited, this process may stabilize the ice sheet in the region by counteracting the landward shift in the touchline of glaciers - the ice flows that flow into the Amundsen Sea include the Thwaites and Pine Island glaciers . The unexpectedly rapid uplift also implies that around 10% more ice has been lost there than previously assumed.

Potential for additional sea level rise in East Antarctica

For a long time it was assumed that the ice sheets of East Antarctica are considerably less sensitive to warming seawater than West Antarctica. In 2015, however, it was found that the Totten Glacier - contrary to previous assumptions - does not rest on solid rock, but in a basin whose underlying water masses are in connection with the open sea. This allows hot water to get under the glacier on a large scale, which explains the strong melting of the glacier that has been observed there in recent years. Since this is an area the size of California, this constellation holds the potential for a further sea level rise by several meters over the next few centuries.

Permafrost soils

In the Antarctic, apart from below glaciers, there are only relatively small areas with permafrost . These are located in Antarctic oases . The largest areas are in Viktorialand (approx. 20,000 km 2 ), East Antarctica (approx. 7,000 km 2 , of which 2,750 km 2 in the Vestfold Mountains , 2,430 km 2 in Queen Maud Land and 1,140 km 2 in Enderbyland ) and on the Antarctic Peninsula (3,800 km 2 ).

In the McMurdo Dry Valleys , the ice-free dry valleys of Viktorialand, permafrost soils that have been stable until now are melting faster than previously expected, mainly due to more intensive solar radiation.

See also

Web links

Individual evidence

  1. ↑ a b Pew Center on Global Climate Change (Ed.): Current Understanding of Antarctic Climate Change.  ( Page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. 2010 (english)@1@ 2Template: Dead Link / research.fit.edu  
  2. ↑ a b Schneider, DP, EJ Steig, TD van Ommen, DA Dixon, PA Mayewski, JM Jones, and CM Bitz (2006): Antarctic temperatures over the past two centuries from ice cores , in: Geophysical Research Letters , 33, L16707 , doi: 10.1029 / 2006GL027057
  3. ↑ IPCC (Ed.): Special Report: Special Report on the Ocean and Cryosphere in a Changing Climate . 2019, 3.2 Polar Regions, Box 3.1 - Polar Region Climate Trends ( ipcc.ch ).
  4. ↑ IPCC (Ed.): Special Report: Special Report on the Ocean and Cryosphere in a Changing Climate . 2019, 3.2 Polar Regions, Executive Summary ( ipcc.ch ).
  5. ↑ a b K. Bryan, S. Manabe, and MJ Spelman (1988). "Interhemispheric Asymmetry in the Transient Response of a Coupled Ocean-Atmosphere Model to a CO 2 Forcing." J. Physical Oceanography '18': 851-67 online
  6. ↑ Barnett, TP, DW Pierce, KM AchutaRao, PJ Gleckler, BD Santer , JM Gregory, and WM Washington. 2005. Penetration of human-induced warming into the world's oceans. Science 309: 284-287
  7. ↑ New Data on Deep Sea Turbulence Shed Light on Vertical Mixing, article on the website of the Wodshole Oceanic Institution WHOI
  8. ^ Kyle C. Armor, John Marshall, Jeffery R. Scott, Aaron Donohoe, Emily R. Newsom: Southern Ocean warming delayed by circumpolar upwelling and equatorward transport . (pdf) In: Nature Geoscience . May 30, 2016. doi : 10.1038 / ngeo2731 .
  9. ↑ aloha-antarctica.de ( Memento of the original from September 22, 2014 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.aloha-antarctica.com
  10. ↑ Shindell, DT and GA Schmidt (2004): Southern Hemisphere climate response to ozone changes and greenhouse gas increases . In: Geophysical Research Letters , Vol. 31, L18209, doi: 10.1029 / 2004GL020724
  11. ↑ Alfred Wegener Institute for Polar and Marine Research How thick is the ice in the Arctic, how thick is it in the Antarctic ( Memento of the original from January 13, 2012 in the Internet Archive ) Info: The archive link has been inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.awi.de
  12. ↑ Gillett, N., and DWJ Thompson. 2003. Simulation of Recent Southern Hemisphere Climate Change. In: Science , Vol. 302, pp. 273–275, doi: 10.1126 / science.1087440 (PDF)
  13. ^ Claire L. Parkinson (2004). Southern Ocean sea ice and its wider linkages: insights revealed from models and observations. Antarctic Science, 16 , pp. 387-400 doi: 10.1017 / S0954102004002214 [1]
  14. ↑ Alfred Wegener Institute for Polar and Marine Research: The deep sea of ​​Antarctica is getting colder - Polarstern has successfully concluded the first Antarctic season in the International Polar Year , press release of April 21, 2008. See online ( Memento des Originals of January 24, 2009 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.awi.de
  15. ↑ Spiegel Online: Deep Sea of ​​Antarctica is getting colder April 21, 2008
  16. ^ Alfred Wegener Institute for Polar and Marine Research: Research ship Polarstern returns from Antarctica
  17. ↑ Geomar.de: Antarctica: Warmth comes from the depths online
  18. ↑ Steig, Eric J .; Schneider, David P .; Rutherford, Scott D. et al. (2009): Warming of the Antarctic ice-sheet surface since the 1957 International Geophysical Year . In: Nature , Vol. 457, pp. 459-462, January 22, 2009, doi: 10.1038 / nature07669 . See also NASA: Satellites Confirm Half-Century of West Antarctic Warming January 21, 2009
  19. ↑ Turner, John, Steve R. Colwell, Gareth J. Marshall et al. (2005): Antarctic Climate Change During the Last 50 Years . In: International Journal of Climatology , Vol. 25, pp. 279–294, doi: 10.1002 / joc.1130 (PDF; 329 kB) ( Memento of the original from January 7, 2009 in the Internet Archive ) Info: The archive link was inserted automatically and not yet checked. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / www.scar.org
  20. ↑ die tageszeitung: It will also be warmer at the South Pole on January 30, 2009
  21. ↑ a b Chapman, WL and JE Walsh (2007): A synthesis of Antarctic Temperatures . In: Journal of Climate , Vol. 20, pp. 4096–4117, doi: 10.1175 / JCLI4236.1 (PDF; 2.5 MB) ( Memento of the original from July 8, 2008 in the Internet Archive ) Info: The archive link was automatically used and not yet tested. Please check the original and archive link according to the instructions and then remove this notice. @1@ 2Template: Webachiv / IABot / igloo.atmos.uiuc.edu
  22. ↑ Shindell, Drew T .; Schmidt, Gavin A. (2004): Southern Hemisphere climate response to ozone changes and greenhouse gas increases . In: Geophysical Research Letters , 31, L18209, doi: 10.1029 / 2004GL020724
  23. ↑ Thompson, David WJ; Solomon, Susan (2002): Interpretation of Recent Southern Hemisphere Climate Change . In: Science , Vol. 296, No. 5569, pp. 895-899, doi: 10.1126 / science.1069270
  24. ↑ IMBIE Team: Mass balance of the Antarctic Ice Sheet from 1992 to 2017 . In: Nature . tape 558 , June 13, 2018, doi : 10.1038 / s41586-018-0179-y .
  25. ↑ Velicogna, Isabella and John Wahr (2006): Measurements of Time-Variable Gravity Show Mass Loss in Antarctica , in: Science, Vol. 311, No. 5768, pp. 1754-1756, doi: 10.1126 / science.1123785
  26. ↑ Wingham, DJ; Shepherd, A .; Muir, A; Marshall, GJ (2006): Mass balance of the Antarctic ice sheet . In: Philosophical Transactions of the Roal Society A , Vol. 364, pp. 1627–1635, doi: 10.1098 / rsta.2006.1792 (PDF; 1.5 MB)
  27. ↑ a b Shepherd, A., and D. Wingham (2007): Recent sea level contributions of the Antarctic and Greenland ice sheets . In: Science , Vol. 315, pp. 1529-1532, doi: 10.1126 / science.1136776 .
  28. ↑ Monaghan, Andrew J., David H. Bromwich, Ryan L. Fogt et al. (2006): Insignificant Change in Antarctic Snowfall Since the International Geophysical Year , in: Science , Vol. 313, No. 5788, pp. 827-831, doi: 10.1126 / science.1128243 .
  29. ↑ NASA Researchers Find Snowmelt in Antarctica Creeping Inland
  30. ↑ Melting ice sheets becoming largest contributor to sea level rise, AGU release no 11-09, March 8, 2011 online
  31. ^ V. Helm, A. Humbert, H. Miller: Elevation and elevation change of Greenland and Antarctica derived from CryoSat-2 . In: The Cryosphere . 8, 2014, pp. 1539-1559. doi : 10.5194 / tc-8-1539-2014 .
  32. ↑ American Geophysical Union of December 2, 2014: West Antarctic melt rate has trippled news from AGU
  33. ↑ Alex S. Gardner et al .: Increased West Antarctic and unchanged East Antarctic ice discharge over the last 7 years . In: The Cryosphere . tape 12 , 2018, p. 521-547 , doi : 10.5194 / tc-12-521-2018 .
  34. ↑ Eric Rignot (1998): Fast Recession of a West Antarctic Glacier , in: Science , Vol. 281, pp. 549-551, July 24, online
  35. ↑ AJ Cook, AJFox, DG Vaughan, JG Ferrigno (2005): Retreating Glacier Fronts on the Antarctic Peninsula over the Past Half-Century , in: Science ., Vol 308, pp 541-544, April 22, online
  36. ^ I. Joughin, BE Smith, B. Medley: Marine Ice Sheet Collapse Potentially Under Way for the Thwaites Glacier Basin, West Antarctica . In: Science . 344, No. 6185, May 15, 2014, pp. 735-738. ISSN  0036-8075 . doi : 10.1126 / science.1249055 .
  37. ↑ E. Domack, D. Duran, A. Leventer, S. Ishman, S. Doane, S. McCallum, D. Amblàs, J. Ring, R. Gilbert, M. Prentice (2005): Stability of the Larsen B ice shelf on the Antarctic Peninsula during the Holocene epoch , in: Nature , Vol. 436, pp. 681-685, June 7, online
  38. ↑ Scambos, TA, JA Bohlander, CA Shuman, and P. Skvarca (2004): Glacier acceleration and thinning after ice shelf collapse in the Larsen B embayment, Antarctica . In: Geophysical Research Letters , Vol. 31, L18402, doi: 10.1029 / 2004GL020670
  39. ^ Wilkins Ice Shelf hanging by its last thread . European Space Agency . July 10, 2008. Retrieved August 8, 2008.
  40. ^ J. Weertmann: Stability of the Junction of an Ice Sheet and an Ice Shelf. In: Journal of Glaciology. Vol. 13, No. 67. 1974 ( Online, PDF ).
  41. ^ JH Mercer: West Antarctic ice sheet and CO2 greenhouse effect: a threat of disaster . In: Nature . 271, No. 5643, January 26, 1978, pp. 321-325. ISSN  0028-0836 . doi : 10.1038 / 271321a0 .
  42. ^ Alley, RB, PU Clark, P. Huybrechts and I. Joughin (2005): Ice-sheet and sea-level changes. In: Science. Vol. 310, pp. 456-460, doi: 10.1126 / science.1114613
  43. ↑ Stefan Rahmstorf : scilogs.de: West Antarctica exceeds the tipping point . SciLogs , September 10, 2014
  44. ^ Robert M. DeConto, David Pollard: Contribution of Antarctica to past and future sea-level rise . In: Nature . 531, No. 7596, March 30, 2016, p. 591. doi : 10.1038 / nature17145 .
  45. ↑ Valentina R. Barletta et al. a .: Observed rapid bedrock uplift in Amundsen Sea Embayment promotes ice-sheet stability . In: Science . tape 360 , no. 6395 , June 22, 2018, doi : 10.1126 / science.aao1447 . See also: Land uplift 'could prevent' collapse of West Antarctic ice sheet. In: CarbonBrief. June 21, 2018, accessed July 14, 2018 .
  46. ^ The University of Texas in Austin, Jackson School of Geosciences: East Antarctica melting could be explained by oceanic gateways , News from March 16, 2015
  47. ↑ Lars Fischer: Warm water gnaws at East Antarctic glaciers. On: Spektrum.de , March 16, 2015. Retrieved April 26, 2015.
  48. ↑ Filip Hrbáček u. a .: Active layer monitoring in Antarctica: an overview of results from 2006 to 2015 . In: Polar Geography . January 2018, doi : 10.1080 / 1088937X.2017.1420105 .
  49. ↑ Ground ice in Antarctica is melting faster and faster. orf / dpa, July 24, 2013, accessed on June 19, 2018 .
  50. ↑ Joseph S. Levy et al. a .: Accelerated thermokarst formation in the McMurdo Dry Valleys, Antarctica . In: Scientific Reports . tape 3 , no. 2269 , 2013, doi : 10.1038 / srep02269 .
  51. ↑ Mauro Guglielmin, Michele Dalle Fratte and Nicoletta Cannone: Permafrost warming and vegetation changes in continental Antarctica . In: Environmental Research Letters . 2014, doi : 10.1088 / 1748-9326 / 9/4/045001 .