The desert climate is a climate in which there is more evaporation than rainfall. The bald, rocky, or sandy surfaces in deserts hold little moisture and evaporate the little rainfall they receive.

Most desert climates receive between 25 and 200 mm (1 and 8 in) of rainfall annually, although some of the most consistently hot areas of Central Australia, the Sahel and Guajira Peninsula can be, due to extreme potential evapotranspiration, classed as arid with annual rainfall as high as 430 mm or 17 in.

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