
Droughts occur when there is no rain or little rain for a long time. When available water falls below demand due to excessive use of the water supply, this can also lead to droughts. Droughts can last months, years or even decades. Soil becomes dry, hard and cracked. Plants cannot grow in damaged soil. There is less water for drinking, farming and wildlife.
Although droughts have always naturally occurred throughout history, climate change is having a large impact. Hotter weather causes water to evaporate, leaving soil drier. In many regions, a warming planet also results in less rain, less snow fall and less snow melt in the spring - less water means drier soil.
The overall frequency of extreme droughts is much more likely due to climate change. On a global scale, it is possible that the tropics and other wet places will get wetter, while deserts and other subtropical dry regions will become drier. Worsening droughts are a characteristic fingerprint of a changing climate.