我国"雨带北移"现象及其水安全风险应对OA

Since 2020,much of northern China has experienced significantly above-average precipitation,with many areas showing anomalies exceeding 50 mm.This has led to the prominent phenomenon of the"northward shift of the rain belt,"accompanied by a northward movement of the boundary between arid,semi-arid,and semi-humid regions.This shift results from the synergistic effect of multiple factors.Specifically,the intensification and northward expansion of the western Pacific subtropical high serve as the direct dynamic force.Natural variability of the climate system,such as the Pacific Decadal Oscillation(PDO)and the El Niño-Southern Oscillation(ENSO),predominantly governs the long-term positional evolution of the rain belt.Climate warming further intensifies the concentration and extremity of precipitation in northern regions.Human activities,including the South-to-North Water Diversion Project and urbanization,have limited influence on this phenomenon.The recent"northward shift of rain belt"is a phase-specific phenomenon.While wetter conditions in northern China may persist for several years,this does not signal a long-term trend of abundant water and cannot alter the decline in surface water resources caused by underlying surface changes in the Haihe River and Yellow River basins.The shift brings both opportunities and challenges:it provides a vital water source for securing water supply and ecological restoration in the north but intensifies flood control pressure and safety risks,thereby raising the demands for disaster prevention,mitigation,and water resources management.It is imperative to strengthen research on the periodic and phase characteristics of the"northward shift of rain belt",enhance monitoring,early warning,and infrastructure resilience,and formulate scientific responses to the water security risks induced by climate change.