Investigation of the interaction between morphometric, hydro-meteorological parameters and climate change in the Vahkin Stream Basin using GIS and satellite data

As the first quarter of the 21st century passes and the second begins, water is emerging as one of the era's most critical concerns. Many argue that it must be addressed urgently, as it is expected to surpass oil in both value and strategic significance. These views are largely shaped by climate change, which profoundly impacts hydro-meteorological dynamics. In this study, the Vahkin Stream Basin, located within the Murat branch of the Euphrates River in Turkey's Eastern Anatolia Region, has been examined. Within the scope of the research, a trend analysis has been conducted using data measured within the basin between the years 1981 and 2022, including average temperature, total precipitation, evapotranspiration, soil moisture, and average flow values. By employing satellite-derived data and utilizing Geographic Information Systems (GIS) tools, the annual, seasonal, and monthly trends of the parameters such as precipitation, temperature, evapotranspiration, soil moisture, and flow belonging to the basin have been analyzed. The aim is to reveal the impact of changes in climate parameters on the Vahkin Basin. Furthermore, as there are very few scientific studies specifically focusing on this basin, it is intended to contribute to the literature regarding climate change specifically within the context of the Vahkin Basin. As methodology, the study employs the Innovative Trend Analysis, the Revised Innovative Trend Analysis, the Innovative Polygon Trend Analysis, the Mann-Kendall Test, the Mann-Kendall Rank Correlation Test, and the Linear Regression method. According to the results obtained, significant, monotonic (uniform) increases in temperature have been observed throughout the basin, while in terms of precipitation, significant, monotonic decreases are found only in the month of November and during the Autumn season, and a significant, monotonic increase is observed in January; apart from these, no other months or seasons exhibit any significant, monotonic increasing or decreasing trends. However, the overall tendency in the precipitation parameter is toward a decrease. While significant, monotonic increasing trends have been identified in evapotranspiration processes, non-monotonic, insignificant decreasing trends have been calculated in soil moisture. Additionally; significant, monotonic decreasing trends have been observed in flow values. As a result of the research, it has been revealed that the observed increases in temperature within the basin have significant impacts on the parameters of evapotranspiration, soil moisture, and flow