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ce sheets[edit]

Main article: Ice sheet

The constant freezing temperatures cause the formation of large ice sheets in ice cap climates. These ice sheets, however, are not static, but slowly move off the continents into the surrounding waters. New snow and ice accumulation then replaces the ice that is lost. Precipitation is nearly non-existent in ice cap climates. It is never warm enough for rain, and usually too cold to generate snow. However, wind can blow snow on to the ice sheets from nearby tundras.

The ice sheets are often miles thick. Much of the land located under the ice sheets is actually below sea level, and would be under the ocean if the ice is removed. However, it is the weight of the ice itself that forces this land below sea level. If the ice was removed, the land would rise back up in an effect called post-glacial rebound. This effect is creating new land in formerly ice cap areas such as Sweden.

The extreme pressure exerted by the ice allows for the formation of liquid water at low temperatures that would otherwise result in ice, while the ice sheet itself insulates liquid water from the cold above. The causes the formation of sub-glacial lakes, the largest beingLake Vostok in Antarctica.