Drought Analysis of the Sanliurfa Province Using the Standardized Precipitation Index (SPI) Method

Droughts are typically defined by negative water budget values in a certain area and time. The development of complex processes and product of insidious and slow processes reveal the difference of drought from other disasters. Droughts occurring on Earth can become multidimensional disasters and affect life completely if not planned and prepared for. In this study on the meteorological dimensions of drought, the drought characteristics of the province of Sanliurfa are discussed. The standardized precipitation index was analyzed in a 12-month time series in the drought analysis. Because precipitation is the only meteorological variable used in the SPI method, the rainfall data of five stations (Sanliurfa center, Akcakale, Birecik, Ceylanpinar, and Siverek) between 1975 and 2019 in Sanliurfa were used. Analysis results were examined in two periods (1975-1997 and 1997-2019) to better understand the increase in drought duration and frequency. The results show that the rates of dry periods in Sanliurfa center and Siverek stations are higher than those of humid periods. It was determined that the rates of humid periods in Akcakale, Birecik, and Ceylanpinar stations are higher than those of dry periods. Moreover, dry periods have increased significantly during the first period considering their trends depending on time, severity, frequency, and the duration of droughts at all stations in the field. This situation reveals the susceptibility and vulnerability of the research area to arid-semiarid climates.