Contrasting Trends in Atmospheric Net Moisture Flux and Its Linkage to Source and Sink Regions Across the Yellow River Basin Over Four Decades

Atmospheric moisture transport and precipitation recycling processes are key to understanding regional water cycle under climate change. Using the two‐layer Water Accounting Model (WAM‐2layers) with ERA5 reanalysis data, we analyzed the atmospheric net moisture flux across the Yellow River Basin from 1980 to 2023. We further applied re‐tracking experiments to separate source and sink dynamics by trend categories. The results show that the basin gains atmospheric moisture flux at an average rate of 0.37 mm day −1 , with peaks exceeding 1.6 mm day −1 in the southwest. Regions with decreasing net moisture flux are dominated by external moisture advection and evaporation losses, with 89.1% of precipitation from advected moisture and 10.9% from recycling. In contrast, regions with increasing net moisture flux show stronger internal regulation through enhanced moisture recycling, with evaporation contributing 74.2% of the moisture budget and net moisture gain the remaining 25.8%. These regions also exhibit stronger source–sink linkages, with correlations exceeding 0.4 and reaching about 0.6. These findings demonstrate that regional water availability in the Yellow River Basin is governed not only by moisture flux magnitude but also by the organization of atmospheric moisture transport pathways.