Hydrological drought analysis and climate characteristics of Ergene Basin with Standardized Precipitation Index (SPI)

Drought is a natural disaster that causes a variety of environmental, social and economic problems. Turkey, which is located in a semi-arid region, often faces the problem of drought. Therefore, determining the time duration and severity of the drought minimizes the possible damages. In this thesis, it is aimed to determine the drought by revealing the climatic characteristics of the Ergene Basin. Thornthwaite climate classification method was used to determine climatic characteristics and Standardized Precipitation Index (SPI) method was used to determine drought status. It is understood that the basin generally shows semi-arid less humid and semi-humid climate characteristics. Within the scope of the study firstly meteorological drought analyzes were carried out with SPI series at different time scales and then hydrological drought analyzes were carried out to examine the field in more detail and to detect deficiencies in groundwater levels. Accordingly, no long-term dry period was detected in meteorological drought analyses. There is an upward trend in SPI-1 values while a smaller increase is observed in SPI-3 values. There is an upward trend in SPI-1 values while a lesser increase is observed in SPI-3 values. In addition in the hydrological drought analysis it is determined that there has been an increase in humidity in Kırklareli, Edirne and Uzunköprü stations in the north and inner parts of the basin in recent years drought tendency in Lüleburgaz-Tigem and Çorlu stations and drought in İpsala and Malkara stations in the South of the basin. In recent years the decrease in precipitation and autumn-winter droughts increase the severity of droughts. Therefore conducting research site-specific studies is important for preventing or reducing the impact of droughts. As a matter of fact this study is important for the determination of drought in the Ergene Basin.