Investigation of the effects of climate changes on precipitation, temperature and evaporation data in Eastern Anatolia Region using trend analysis methods

In today's world where the effects of global climate change are becoming increasingly evident, determining trends in hydro-meteorological parameters (precipitation, temperature, evaporation, etc.) is of great importance in terms of sustainable management, planning and design of engineering projects of water resources. In this context, various methods for trend analysis have been developed and studies have increased to reveal climatic changes at the regional level by applying them to climate data. In this study, the Eastern Anatolia Region located in the east of Türkiye was selected as the research area and monthly total precipitation, temperature and evaporation data covering the water years 1977–2023 obtained from the General Directorate of Meteorology stations located in the centers of 13 provinces of the region were analyzed. In trend analyses; Mann-Kendall test, Wilcoxon Combination Test and Innovative Trend Analysis methods were used. In temperature data, a significant positive trend was detected at the 95% confidence level in most stations. In precipitation data, trends were found to be weaker and spatially variable, and a consistent positive trend was detected only at the Ardahan station. Due to deficiencies in evaporation data, analysis could not be performed for this parameter. In general, the temperature increase in the region has become apparent, and precipitation trends have a more complex structure. Mann-Kendall, Wilcoxon Combination Test and Innovative Trend Analysis methods largely supported each other in temperature data; however, in precipitation data, they produced consistent results only for some stations. Ardahan station stands out in particular in terms of showing a consistent positive trend in all methods.The findings show that climate change has significant effects on the temperature parameter in the Eastern Anatolia Region, and provide an important data source for future climate modeling and regional water management policies.