Map of annual snow accumulation on Antarctica The climate of Antarctica is cold and dry. Antarctica is the coldest place on earth. The lowest temperature ever recorded on earth was -89.4 °C (-129 °F) recorded in 1983 at Vostok Station. The highest temperature ever recorded in Antarctica was 14.6 C (58.3 F) in Hope Bay. Weather patterns rarely penetrate far into the continent, leaving the center cold and dry. There is little precipitation over the continent, but ice there can last for a long time. Nearly all of Antarctica is covered by an ice sheet that is, on average, 2.5 kilometres thick. If all the land-ice covering Antarctica were to melt - that's around 30 million cubic kilometres of ice - the seas would rise by over 60 metres. This is, however, very unlikely within the next few centuries. However, the Antarctic is so cold that even increases of a few degrees, temperatures would generally remain below the melting point of ice. Warmer temperatures are expected to lead to more snow, which would increase the amount of ice in Antarctica, with a consequent (smallish) offsetting of the expected sea level rise from thermal expansion of the oceans. For the contribution of Antarctica to present and future sea level change, see sea level rise. Climate History of Antarctica
After splitting from Gondwana, Antarctica drifted slowly to its present position over the South Pole. Its climate was much warmer before its polar approach. There may have been significant ice sheets 30 million years ago. It has been covered with ice since approximately the beginning of the Pliocene, about 5 million years ago. Marginal ice shelves around the Antarctic Peninsula have been lost since 1950. Prince Gustav Channel was blocked until 1995 by ice which did not exist from about 6500 years ago to 1900 years ago, including most of the Holocene Climatic Optimum and through part of the following cooler period.
References - Vaughan, D. G., G. J. Marshall, W. M. Connolley, J. C. King, and R. M. Mulvaney, 2001: “Devil in the detail” . Science, 293, 1777-1779
- Review of above: http://www.co2science.org/journal/2001/v4n39c3.htm
External links Climate - http://www.antarctica.ac.uk/met/gjma/ - climate data from Antarctic surface stations with trends
- http://www.antarctica.ac.uk/met/READER/ - temperature data from the READER project
- http://www.antarctica.ac.uk/met/jds/weather/weather.htm - a pamphlet about the weather and climate of Antarctica
- http://www.antarctica.ac.uk/met/bas_publ.html - information concerning recent ice shelf calving
- http://www.antarctica.ac.uk/met/climate/wmc/ - (unreliable) maps of snowfall and temperature
- Temperature statistics (http://www.nerc-bas.ac.uk/icd/gjma/pole.temps.html) at the Amundsen-Scott station on the South Pole
- http://www.science.org.au/nova/082/082key.htm
Climate Change in Antarctica - http://www.antarctica.ac.uk/Key_Topics/Climate_Change/Climate_Change_Position.html
- http://www.antarctica.ac.uk/Key_Topics/IceSheet_SeaLevel/ice_shelf_loss.html
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