West Antarctic Ice Sheet

ice sheet, Antarctica

Also known as: WAIS

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Last updated

July 15, 2026

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The West Antarctic Ice Sheet (WAIS) is a massive ice sheet covering much of West Antarctica. It is composed of ice that has accumulated over millions of years and contains a significant portion of the world's fresh water. The WAIS is divided into East and West Antarctica by the Transantarctic Mountains.123

A key component of the WAIS is the Thwaites Glacier, which has the widest glacial interface with the ocean globally. Scientists are concerned about the stability of the WAIS, particularly the Thwaites Glacier, due to rising ocean temperatures caused by global warming. If the WAIS were to melt entirely, it could lead to a global sea level rise of approximately 10.5 meters (34 feet). Current research indicates that changes in the WAIS could have worldwide effects.451

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glacier
West Antarctica
The part of the main continent lying south of the Americas, between longitudes 45° W and 165° E, is characterized by irregular bedrock and ice-surface topography and numerous nunataks and deep troughs. Two large ice shelves occur in West Antarctica: the Filchner-Ronne Ice…
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The part of the main continent lying south of the Americas, between longitudes 45° W and 165° E, is characterized by irregular bedrock and ice-surface topography and numerous nunataks and deep troughs. Two large ice shelves occur in West Antarctica: the Filchner-Ronne Ice…
Read More

Antarctica
The surrounding seas
…Cenozoic time and that the West Antarctic Ice Sheet did not form until about 10 million to 5 million years ago, which is much later than inferred from evidence on the continent itself. Drilling of the Kerguelen Plateau near the Amery Ice Shelf (1987–88) entailed the study of the rifting…
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…Cenozoic time and that the West Antarctic Ice Sheet did not form until about 10 million to 5 million years ago, which is much later than inferred from evidence on the continent itself. Drilling of the Kerguelen Plateau near the Amery Ice Shelf (1987–88) entailed the study of the rifting…
Read More