Drought - a long period without precipitation or precipitation minor compared to the average perennial value. Causes drying of the soil, reduction or complete destruction of crop maintenance (and thus the famine), reduced drinking water supplies, as well as the increased likelihood of catastrophic fires.
There are atmospheric drought, soil, and physiological.
* Atmospheric drought occurs when for 20 days there is no rain
* Soil drought is water shortage in the soil, causing losses in agriculture
* physiological drought in the environment is water, but can not be retrieved
Atmospheric and soil droughts disappear relatively quickly.