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• Human impact on droughts

Drought is an extended period of exceptionally low precipitation. A drought can feature additional weather characteristics, including high temperatures and high winds.

Although low precipitation (rain, snow, or sleet) marks both droughts and deserts, the two are different. A desert is a region that experiences low precipitation as an everyday occurrence. A drought, on the other hand, is a temporary condition in which precipitation is abnormally low for a particular region. Droughts may occur at any time in any part of the world and last anywhere from days to weeks to decades.

The U.S. National Weather Service recognizes three categories of drought. A dry spell occurs when there is less than .03 inch (.08 centimeter) of rainfall during a minimum of 15 consecutive days. A partial drought occurs when the...