The Rapid Intensification of East Asian Cyclones Around the Korean Peninsula and Their Surface Impacts

Abstract The rapid intensification of extratropical cyclones (ETCs) around the Korean peninsula and their surface impacts are investigated by detecting and tracking ETCs in East Asia using ERA‐Interim data over the period of 1979–2017. The ETCs approaching the Korean peninsula, identified on the 850‐hPa relative vorticity field, are mainly initiated in the leeward side of the Altai‐Sayan Mountains and southern Tibetan Plateau, featuring northern and southern cyclone tracks, respectively. The northern‐track ETCs are typically accompanied by a developing upper‐level trough. In particular, those that intensify rapidly are characterized by a strong upper‐level potential vorticity (PV) anomaly related to the enhanced trough, with a rather weak influence of diabatic heating. This is in contrast with the southern‐track ETCs, which are primarily organized by a lower‐level PV anomaly produced by …