Drought refers to water scarcity and reduction of streamflow, reduction in lake or reservoir storage, and lowering groundwater levels due to a lack of rainfall and intense sunshine. In the past, drought intensity was evaluated based on the number of consecutive drought days. These days, it is determined by the duration of water scarcity and the extent of the regions affected.

 Drought damage includes industrial damage, human injury, and loss of life due to water scarcity. Water scarcity means not only a huge decrease in water volume, groundwater, and soil moisture, but also reduced productivity due to industrial water shortages. In Korea, droughts often occur when a Jangma (East Asian monsoon) front is moving north due to high pressure in the North Pacific High during the summer, which prevents and restricts precipitation.