The Dry Valleys: Driest Place on Earth - Antarctica
One interior region of the Antarctic is known as The Dry Valleys. These valleys have not seen rainfall in over two million years. With the exception of one valley, whose lakes are briefly filled with water by inland flowing rivers during the summer, the Dry Valleys contain no moisture (water, ice, or snow).
The reasons why the Dry Valleys exist are the 200 mph Katabatic down winds which evaporate all moisture. The dry valleys are strange: except for a few steep rocks they are the only continental part of Antarctica devoid of ice. Located in the Trans-Antarctic Range, they correspond to a mountain area where evaporation (or rather, sublimation) is more important than snowfall, thus all the ice disappears, leaving dry barren land.
Another driest place is the Atacama Desert in Chile, some parts of which have received absolutely zero precipitation in centuries. Parts of the Atacama Desert may actually exceed the dryness of most of Antarctica, though data from the latter is insufficient to tell.
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