Lake Powell during drought.

DROUGHTS

Droughts are periods with insufficient rain, enough to jeopardize life and property.

Droughts are natural; they will always happen.

Droughts have intensity-duration-frequency relations which vary across the climatic spectrum.

Droughts are more frequent and more intense in arid and semiarid regions.

Droughts can be intensified by anthropogenic action [desertification].

Civil engineers deal with droughts by building multiannual storage reservoirs.