What polar desert covers almost all of Antarctica?

What polar desert covers almost all of Antarctica? The answer is the Antarctic desert.

Antarctica qualifies as a desert because it receives very little precipitation, not because it is warm or sandy. The continent averages roughly 150–166 millimetres of precipitation per year, mostly as snow, and the interior receives much less. About 98% of Antarctica is covered by the Antarctic ice sheet, making it the world’s largest ice desert.

The ice sheet averages about 1.6 kilometres in thickness and stores most of Earth’s fresh water. Cold air holds little moisture, while katabatic winds help keep the high interior exceptionally dry. Some areas, including the McMurdo Dry Valleys, are so arid that they resemble rocky deserts despite their polar setting.

A common mix-up is treating the Arctic and Antarctic as equivalent deserts. The Arctic is an ocean surrounded by land, whereas Antarctica is a high continental landmass covered by ice. Antarctica is also much colder: Vostok Station recorded −89.2°C in 1983, the lowest officially recognized natural air temperature on Earth. Coastal areas are wetter and milder than the continental interior.