Why is Antarctica called a desert? A Desert is a place with less than 254 mm (10 in) of annual rainfall. This is what makes Antarctica a desert. There is virtually no rainfall in Antarctica - it is so cold it only ever snows. Snowfall is measured in "water equivalent". This is the amount of water you would get if the snow was collected and melted. Antarctica gets only about 50 mm (about 2 in) of "water equivalent" per year, this is less than the Sahara. This is more near the coasts but still only about 200 mm (8 in) in "water equivalent". Heavy snowfall can happen when storms pick up moisture from the seas surrounding Antarctica and then drop this as snow along the coast.
The big difference in Antarctica is that unlike other deserts falling water (snow) doesn't evaporate. So even though there is only a small amount of snow falling, it doesn't go away again. Instead it builds up over hundreds and thousands of years into enormously thick ice sheets. coolantarctica.com
Musiktipp: "Pinguin in der Wüste" - Von Luft und Liebe - mp3.
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