What Is Drought?

Drought occurs when there is less than normal precipitation over an extended period. Drought may last from a few weeks to many years and occurs in virtually all climate zones. It is different from aridity, which is a feature of climate in regions where precipitation is typically low, such as in a desert.

Drought means different things to different people. For example, to a farmer, just a few weeks without rain during the growing season may mean crop loss. To a water manager, drought means lowered reservoir levels and affected drinking supply. Drought is commonly categorized as meteorological, agricultural, hydrological, or socioeconomic, reflecting the different aspects of the Earth system and society that it affects.