The Effects of Agricultural Drought on Crop Production

Drought, defined as a shortage of precipitation, soil moisture, and vegetation greenness, is characterized by abnormal decreases in precipitation. In the past, drought was determined by comparing a particular year's precipitation with the long-term average precipitation. However, scientists now recognize that drought severity should be assessed based on magnitude. To address this, various drought indices, including AI, SPI, CZI, and SPEI, have been developed. Among these, SPI is the most commonly used for drought assessment. Despite its wide use, SPI has limitations for agricultural drought assessment, as it only considers total precipitation and does not account for factors such as runoff and evapotranspiration.