Three types of drought are distinguished: 1) soil drought, that is, soil moisture is at the limit of the lowest moisture capacity; 2) a sharp decrease in relative humidity in the air; 3) it is the dryness of the soil due to the dryness of the air.

Drought covers ever larger areas of the Earth. Global warming is causing a decrease in arable land and grazing land. This, in turn, in many parts of the world, during the drought period, results in widespread destruction of greenery and forests due to dehydration, and in some cases, strong fires in forests, crops and pastures, at the same time, the dry winds blowing during this period greatly increase the danger of fire. When forest fires occur during the drought period, it is no longer possible to restore the forest cover, gradually the forests are replaced by deserts. According to the United Nations, 85% of the Earth's land area has been affected by drought, which has led to poverty and hunger in drought-prone countries. Currently, the number of ecological migrants on the planet has already exceeded 24 million, and it is predicted that their number will increase rapidly by 2050.From an agricultural point of view, drought is the absence of precipitation on the earth's surface for a long period of time. During the dry season, the air temperature is high and the relative humidity is very low. In this regard, in order to meet the irrigation water demand of agricultural plants, changes are made in the irrigation regime, that is, the number of irrigations and the irrigation rate are increasing. Drought is one of the disasters that cause the most economic losses and is among the most dangerous disasters in terms of the number of victims of all existing natural disasters.

Drought is considered one of the most dangerous natural phenomena for the plains and foothill regions of Azerbaijan. In the mentioned regions, there are dry years when there is no precipitation in spring and summer.