Of all natural disasters, drought is the most subtle. Often, farmers cannot tell there is going to be a drought until it is too late. Unlike flash floods, drought is slow to develop. Unlike earthquakes, with destruction to the exterior environment, drought does its damage underground long before dust storms rage across the plains.

Technically, drought is measured by the decrease in the amount of subsoil moisture that causes crops to die or yield less (agricultural drought) or by a drop in the water level in surface reservoirs and below ground aquifers, causing wells to go dry (hydrological drought). Agricultural plus hydrological drought can lead to sociological drought. In this condition, drought effects food and water supplies to the extent that people have to rely on relief donations or are forced to migrate to another area.

Droughts are worldwide, repetitive, and unpredictable. Scientists believe there is a drought...