Hydrological Droughts in the Eastern Mediterranean Basin Using Hybrid Trend Analysis Methods

This study investigates the impact of climate change on river systems within the Eastern Mediterranean Basin (EMB), utilizing the Mann-Kendall (MK) test, enhanced by Sen’s slope estimator and Şen’s Innovative Trend Analysis (ITA) methods. The research focuses on hydrological changes in river systems, particularly streamflow trends, and their implications under climate change and anthropogenic activities. The methodology includes a detailed analysis of hydro-meteorological series, including streamflow data from different observation stations. To satisfy the serial independence requirement assumption of MK test pre-whitening and over-whitening methodologies are applied effectively. The study area comprises 10 sub-basins in the EMB, with particular attention to the Göksu River and its tributaries. The results clearly show significantly decreasing trends in the annual streamflow values at several stations, demonstrating the considerable influence of climate and environmental changes on the basin's hydrology. These trends are also critically analyzed with the help of ITA graphs, which provide insights into the spatial and temporal variability of streamflow patterns. This research contributes to a better understanding of hydrological responses to climatic variability, providing vital information for water resource management and policies in regions undergoing significant environmental changes.