Effects of the East Asian Summer Monsoon on Tropical Cyclone Genesis over the South China Sea on an Interdecadal Time Scale

Tropical cyclone (TC) genesis over the South China Sea (SCS) during 1965--2004 was analyzed. The locations of TC genesis display evident seasonal changes, with the mean position of formation situated north of 15oN in summer (June--July--August) and south of 15oN in autumn (September--October--November). The TC genesis in summer underwent dramatic interdecadal variations, with more and less TC frequency during 1965--1974/1995--2004 and 1979--1993, respectively. In contrast, a significant interannual variation of TC genesis with a period of ～4 years was observed in autumn.