Drought assessment using the reconnaissance drought index (RDI): A case study of Eastern Mediterranean, Seyhan, Ceyhan, and Asi basins of Turkey

In this study, drought analysis was carried out in the region, which includes the Eastern Mediterranean, Seyhan, Ceyhan, and Asi basins located in the south of Turkey. In total, data from 35 meteorological stations has been analyzed. As a drought index, the Reconnaissance Drought Index (RDI) was utilized. The Thornthwaite method was selected in the calculation of Potential Evapotranspiration (PET). According to the results, the PET values of all stations have increased in recent years. 3-, 6-, 9-, and 12-month RDI values have been plotted based on the hydrological years. As stated by RDI results, there was mild drought in the basin. The drought results obtained by Turkish State Meteorological Service (The Ministry of Agriculture and Forestry General Directorate of Meteorology) with the Standardized Precipitation Index (SPI) method were compared with the results in this study. In this study, drought mapping for RDI was carried out using the annual values of stations with common observation years to monitor visually spatial spread of the drought.