[A-AS04] Extreme Events and Mesoscale Weather: Observations and Modeling

[AAS04-P11] Local-scale circulation associated with enhanced poleward moisture transport for Meiyu-Baiu heavy rainfall over western Japan

*飯塚 聡¹、松村 伸治¹ (1.国立研究開発法人　防災科学技術研究所)

キーワード：豪雨、海面水温、黒潮

Heavy rainfall events in western Japan during early July have become more frequent, yet the underlying mechanism behind this trend during the late stage of the Meiyu-Baiu rainy season remains unclear. Our long-term analysis of short-duration events revealed that a quasi-stationary Rossby wave train enhances the poleward transport of moisture from the western Pacific, contributing to the frequent occurrence of heavy rainfall events over western Japan. The local-scale circulation over the East China Sea plays a substantial role in producing this quasi-stationary Rossby wave train, which is closely linked to enhanced deep convection over the Kuroshio warm current, characterized by a distinct sea surface temperature (SST) front.