资源环境科技发展态势分析平台

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 diabatic heating. The southern-track ETCs rapidly intensify in the presence of a migrating upper-level trough through the interaction of upper- and lower-level PV anomalies. Although their intensification processes differ, surface winds reaching 10 m s(-1) are observed with the rapid intensification of both northern- and southern-track ETCs. The southern-track ETCs, traveling across the East China Sea and the Yellow Sea, also result in substantial precipitation in Korea and Japan.