In 2007, the tropical cyclone activity over the Northwest Pacific exhi bits the following features as compared to normal years: (1) the active tropical cyclone season shifts about 2 months later; (2) the area of tropical cyclogenes is is more northward and abrupt changes in latitudes of genesis occur twice in t he year; (3) the intensity of tropical cyclone as a whole is slightly weaker whi le individual one is more intense; and (4) there is a higher rate of landfall tr opical cyclones. These characteristics are associated with ENSO phenomenon which turns from El Nino to La Nina in the year. Consequently, a more favorable envir onment for tropical cyclones occurs since August, including the strengthened lar gescale ascending motions and ITCZ, the northward subtropic high, small local v ertical shear, and active turbulences in low troposphere.