Drought is period or condition of unusually dry weather within a geographic area where rainfall is normally present. During a drought there is a lack of precipitation. Drought occurs in all climatic zones. However, it's characteristics very significantly from one region to another.

    Drought usually results in a water shortage that seriously interferes with human activity. Water supply reservoirs are empty, well dry up, and crop damage follows. Its seriousness depends on the degree of water shortage, size of are affected, and the duration and warmth of the dry period. In many underdeveloped countries, such as India, people place a great demand on water supply. During a drought period there is a lack of water, and thus many of the poor die.

    Most precipitations depend on water vapor carried by winds from an ocean or other source of moisture. If these moisture - carrying winds are replaced by winds from a dry region. or if they are modified by downward motion, as in the center of an anticyclone, the weather is abnormally dry and often persistently cloudless. If the drought period is short, it is known as a dry spell. A dry spell is usually more than 14 days without precipitation, whereas a severe drought may last for years.  

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