A 36-year Climatology of Surface Cyclogenesis in East Asia Using High-resolution Reanalysis Data

In this study, the frequency of surface cyclogenesis and the surface cyclone track in East Asia are investigated using high-resolution and long-term reanalysis data, which are ERA40 data in a reduced Gaussian grid system. A cyclone center was identified in the surface pressure anomaly using a modified method after Serreze (1995). Surface cyclogenesis frequently occurs in several specific areas in all seasons. The broadening of the frequent areas is mostly narrower than those shown in previous studies. The areas of high-frequency cyclogenesis are distributed in the lee of mountains, basins, the Pacific Ocean to the east of Japan, the Japan Sea, the Kuroshio Current region to the south of Japan, and the East China Sea. In particular, this study showed newly several findings; the inactive cyclogenesis in the lee of Tahsinganling in summer; the frequent cyclogenesis in the Hebei Plain except for summer; and the cyclogenesis maxima around the mouth of the Yangtze River and in the East China Sea to the northeast of Taiwan in winter.