Drought

drought

(Sometimes spelled drouth.) A period of abnormally dry weather sufficiently long enough to cause a serious hydrological imbalance.
Drought is a relative term, therefore any discussion in terms of precipitation deficit must refer to the particular precipitation-related activity that is under discussion. For example, there may be a shortage of precipitation during the growing season resulting in crop damage (agricultural drought), or during the winter runoff and percolation season affecting water supplies (hydrological drought).
Compare dry spell.
See absolute drought, partial drought, flash drought.

Term edited 18 November 2019.

Any function of time f(t) is periodic with period t if f(t) = f(t + τ) for all times t, where τ is the smallest number for which this equality holds.

A division of the year according to some regularly recurrent phenomena, usually astronomical or climatic.