基于改进水量-能量空间坐标分解法的黄河流域实际蒸散发变化归因分析OA北大核心CSTPCD

In order to investigate the impacts of climate change and human activities on evapotranspiration(ET)over the Yellow Rive Basin(YRB),the spatial and temporal evolution of ET during the period of 1961-2020 and its influencing factors were analyzed based on the latest ERA5 Land reanalysis data.Then,the improved water-energy spatial coordinate decomposition method was adopted to quantify the contributions of climate change and underlying surface change to the variation of actual ET over the YRB.The results show that the water-energy spatial coordinate decomposition method used in this study is clear in principle,simple in calculation,and practicable in application.Moreover,the actual ET and precipita-tion decreased significantly from 1960-2020 over the YRB,with the decreasing rates of 4.5 and 15.9 mm/10a,respectively.However,the potential ET and aridity index showed significant increasing trends,with the increasing rates of 24.4 mm/10a and 0.078/10a,respectively.The decrease of actual ET was mainly seen in the middle and lower reaches of the Yellow River;whereas a certain increase was spotted in the source area.The quantitative attribution analysis indicate that climate change caused the decrease of the actual ET,with a contribution rate of 79%;while the underlying surface variation was responsible for the increase of the actual ET,with a contribution rate of 21%.Therefore,climate change is the main influencing factor of actual ET.The study is expected to provide a technical reference for the water re-sources utilization and high-quality development over the YRB in the future.