Precipitation and Pan Evaporation Patterns in YHH Basin (1950-2023): Analysis and Influencing Factors

Considering the vital importance of the Yellow River-Huai River-Haihe River (YHH) basin in national food security and water resource management, a thorough investigation into the spatiotemporal distribution of precipitation and pan evaporation, along with the factors that influence these phenomena, is essential for the region's agricultural productivity, economic growth, and cultural sustainability. To this end, daily meteorological data from 159 stations across the YHH basin from 1950 to 2023 were hereby utilized for exploration. Advanced methods such as Kriging spatial interpolation, regression analysis, Mann-Kendall trend analysis, and wavelet analysis were employed to elucidate the spatial distribution, interannual variability, and periodicity of precipitation and evaporation. Furthermore, Pearson correlation analysis was conducted to examine the inter relationships among various meteorological elements, while a multi-year monthly mean model was used to analyze the monthly variation patterns of regional precipitation and evaporation within a year. Moreover, the center of the gravity migration model was introduced to reveal the spatiotemporal evolution patterns of these meteorological elements. Overall, this research breaks new ground by examining the seasonal dynamics between precipitation and pan evaporation in the YHH basin and their implications for agricultural irrigation. The insights gained provide vital scientific backing for developing regional land management strategies, guiding crop cultivation plans, and fostering agricultural resilience in the face of climate change.