Increasing warm-season precipitation in Asian drylands and response to reducing spring snow cover over the Tibetan Plateau

Abstract Precipitation is crucial for life and the ecological environment in Asian drylands. This study investigated precipitation trends drylands previous four decades simulated its possible linkage with snow cover reduction over Tibetan Plateau. The results show that has been increasing contributing to wetter conditions can be attributed deepened quasi-stationary wave trough around Lake Balkhash meridional water-vapor flux originated from Arabian Sea Bay of Bengal. mid-latitude waves eddy disturbances correspond northward upper-level Plateau (TP) mode South High (TP-SAH) Afro-Asia jet cyclonic rotation. Both SAH anomalies strengthen ascending motion convergence drylands, those are favorable summer precipitation. anomalous circulations linked following: (1) reduced (SC) west TP late spring decreasing soil moisture diabatic heating favors extension TP-SAH jet; (2) TP/SC increases surface temperature northeast Asia, which decreases gradient between Indian Ocean, Asia East Asia. Decreased gradients beneficial southwest-northeast rotation consequently southerly wind surrounding regions. emphasizes important effects reducing on intensifying