Trends in the annual maximum accumulated precipitation deficit and surplus in the Upper Ceyhan River Basin

Flood and Drought, despite each is being different from the other, they are considered hydrological hazards that affected most societies in the past and will probably occur in future. These extreme events had influenced the developed and developing countries which had negatives consequences on socio-economy and environment. This situation is due to climate change. Studies using monthly precipitation data are important for the determination of climate change impacts. An early prediction of these impacts shows the importance of trend analyses methods. In this study, the trend analyses of annual maximum accumulated precipitation deficit, deficit duration (DD), surplus and surplus duration (SD) will be analyzed for the upper Ceyhan River Basin. Trend analyses in calculated Standard Precipitation Index (SPI) data for 1 month, 3 months and 6 months periods were determined by Mann-Kendal's test and the amount of this trend was calculated by Sen's Slope test. In addition, the homogeneity of the data was checked by the Wallis and Moore test, and the change points were determined by using the Buishand Range test.