Antarctic Ice Sheet

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Antarctic Ice Sheet

ice sheet, Antarctica

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July 23, 2026

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The Antarctic Ice Sheet is a massive body of ice covering approximately 13.8 million square kilometers (5.3 million square miles) of the continent of Antarctica. It holds about 70 percent of the world's fresh water. This ice sheet is composed of East and West Antarctic ice sheets, separated by the Transantarctic Mountains. The ice's mean thickness is about 1,829 meters (6,000 feet), with a volume exceeding 25.4 million cubic kilometers.1234

The ice sheet's mass is maintained by snowfall, balanced by the loss of ice through melting and the calving of icebergs. While the ice sheet is generally considered to be in equilibrium, changes in iceberg calving and ice shelf melting can influence global sea levels. The climate in Antarctica is extremely cold, with temperatures on the polar plateau being the coldest on Earth.256

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glacier
Antarctic Ice Sheet
The bedrock of the continent of Antarctica is almost completely buried under ice. Mountain ranges and isolated nunataks (a term derived from Greenland’s Inuit language, used for individual mountains surrounded by ice) locally protrude through the ice. Extensive in area are…
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The bedrock of the continent of Antarctica is almost completely buried under ice. Mountain ranges and isolated nunataks (a term derived from Greenland’s Inuit language, used for individual mountains surrounded by ice) locally protrude through the ice. Extensive in area are…
Read More

glacier
Glaciers and sea level
…balance, the status of the Antarctic Ice Sheet is uncertain, and, although the floating ice shelves and glaciers may be in a state of negative balance, the melting of floating ice should not cause sea level to rise, and the grounded portions of the ice sheets seem to be growing.…
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…balance, the status of the Antarctic Ice Sheet is uncertain, and, although the floating ice shelves and glaciers may be in a state of negative balance, the melting of floating ice should not cause sea level to rise, and the grounded portions of the ice sheets seem to be growing.…
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Antarctica
Glaciation
The Antarctic Ice Sheet seems to be approximately in a state of equilibrium, neither increasing nor decreasing significantly according to the best estimates. Snow precipitation is offset mainly by continental ice moving seaward by three mechanisms—ice-shelf flow, ice-stream flow, and sheet flow. The greatest volume loss…
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The Antarctic Ice Sheet seems to be approximately in a state of equilibrium, neither increasing nor decreasing significantly according to the best estimates. Snow precipitation is offset mainly by continental ice moving seaward by three mechanisms—ice-shelf flow, ice-stream flow, and sheet flow. The greatest volume loss…
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iceberg
Impacts on ice sheets and sea level
The Antarctic Ice Sheet has a volume of 28 million cubic km (about 6.7 million cubic miles), which represents 70 percent of the total fresh water (including groundwater) in the world. The mass of the ice sheet is kept in balance by a process of gain and…
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The Antarctic Ice Sheet has a volume of 28 million cubic km (about 6.7 million cubic miles), which represents 70 percent of the total fresh water (including groundwater) in the world. The mass of the ice sheet is kept in balance by a process of gain and…
Read More

polar ecosystem
The Antarctic region
…are the harsh climate, the ice cover that completely engulfed the continent during the Pleistocene glaciations, and the present limited number of ice-free land areas, which are restricted primarily to the coastal fringes and nunataks (mountain peaks surrounded by the ice cap). As a consequence, the terrestrial flora and fauna…
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…are the harsh climate, the ice cover that completely engulfed the continent during the Pleistocene glaciations, and the present limited number of ice-free land areas, which are restricted primarily to the coastal fringes and nunataks (mountain peaks surrounded by the ice cap). As a consequence, the terrestrial flora and fauna…
Read More