Investigation of Meteorological Drought Indices for Environmental Assessment of Yesilirmak Region

Abstract

Generally, as drought, inadequate rainfall means; the concept of drought is not just about reducing rainfall. When years of humidity in an area are lower than average, this is caused by the disruption of our balance between rainfall and evapotranspiration. The reason for droughts is not always the same. It is also difficult to estimate the start and end of the drought. Drought, a mysterious pest, has emerged mysteriously, showing its effects slowly and it goes on for a long time. In this study, drought analysis of the Yesilirmak River basin area in the Black Sea region between 1970 and 2014 was performed. Initially to conduct research, meteorological stations in the basin area that had been collecting data for a long time were investigated, required hydro meteorological data have been obtained from the Meteorological Office which is calculated accurately based on meteorological drought values. Rainfall and drought performance have been investigated with different indices. In this study, monthly precipitation data for inland basin stations, with 7 different meteorological drought indices (PN, DI, RAI, ZSI, CZI, MCZI and SPI) on 7 time scales 1,3,6,12,24,36 and 48 are used and so there is a comparison between drought indices and time periods and all droughts were also recorded during the study period. Finally, the 12-month SPI index was selected as the best index and time scale for the basin and the drought maps for the area were extracted using the SPI index results. © 2020, Dorma Journals. All rights reserved.