Abstract:

This study aims to analyze the trends and abrupt changes in hydrometeorological variables in the Yarkand River basin and their correlations with hydroelectric power generation. Various analytical methods, including the Mann-Kendall trend test and the Maximum Mutual Information Coefficient, were employed to investigate these aspects over the period from 1960 to 2017. Findings indicated that precipitation, temperature, and runoff exhibited significant increasing trends during this period, whereas evapotranspiration and wind speed showed notable decreases. Specifically, the upward trends in precipitation and runoff were more pronounced during the flood period, with rates of 0.49 mm/year and 0.86 mm/year, respectively, approximately 4.1 and 2.4 times those of the dry period. Seasonal analysis revealed significant upward trends in temperature and runoff across all seasons. Notably, significant increases in evapotranspiration were primarily observed during summer and autumn. Except from wind speed,abrupt changes in these hydrometeorological elements were detected around the 1990s, with multiple shift points observed in precipitation data. Hydropower generation was found to be directly linked to runoff, which is influenced by factors such as snowpack, air temperature, and soil temperature. As temperature rises, snow and ice melt accelerates, leading to increased runoff and consequently higher hydropower generation capacities.

Key words: Yarkand River Basin, trend analysis, maximum mutual information coefficient, climate change, hydroelectric power generation