Antarctic ice sheet
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A satellite composite image of Antarctica |
The
Antarctic ice sheet is the largest single mass of
ice on
Earth. It covers an area of almost 14 million square km and contains 30 million cubic km of ice. Around 90 percent of the
fresh water on the Earth's surface is held in the ice sheet, an amount equivalent to 70 m of water in the world's oceans. In
East Antarctica, the ice sheet rests on a major land mass, but in
West Antarctica the bed can extend to more than 2500m below sea level. The land would be seabed if the ice sheet were not there.
[British Antarctic Survey]Ice enters the sheet through snow and frost and leaves by calving of
icebergs and melting, usually at the base but also sometimes at the surface at warm sites
[British Antarctic Survey: The Antarctic ice sheet and rising sea levels].
Recent satellite data reported by
NASA shows evidence that the total amount of ice in Antarctica has increased in the past few decades. This is significant because there is a large amount of ice in the area and some climate models predicting global warming also predict that some of the most severe warming would occur in Antarctica. This melting ice would raise sea levels significantly
[http://www.gsfc.nasa.gov/topstory/20020820southseaice.html]. On the other hand, a warming climate in the southern hemispehere would transport more moisture to Antarctica so the ice sheet would in fact grow and somewhat counteract rising sea levels.
[British Antarctic Survey: The Antarctic ice sheet and rising sea levels]*
West Antarctic Ice Sheet*
polar ice*
ice sheet*
ice shelf*
Ross Ice Shelf*
Geography of Antarctica
