Spatiotemporal analysis of droughts in Hirfanli Dam basin, Turkey by the Standardised Precipitation Evapotranspiration Index (SPEI)

Drought is generally defined as a disaster affecting vital activities negatively because of water scarcity as a result of precipitation falling below the recorded normal levels. In the present study, the Standardized Precipitation Evapotranspiration Index was applied for the first time in Hirfanli Dam basin, which has the characteristics of a semiarid climate in Turkey. The annual drought events in the basin between 1968 and 2017 were investigated by using the precipitation and temperature data obtained from Gemerek, Kayseri, Kirsehir, Nevsehir, Sivas, and Zara meteorology observation stations located in Hirfanli Dam basin. The dry and wet years were determined in the basin, and evaluations were made in this respect. The years when the most severe droughts happened in the basin were determined, and drought maps, which showed the spatial distribution of drought, were prepared. In the light of the analyses and maps made, it was found that the most severe drought happened in 2001 in Hirfanli Dam basin.