EFFECT OF ENVIRONMENTAL FIELD ON TROPICAL CYCLONE TRACK AFTER LANDFALL FROM EAST CHINA SEA

A composite study is performed on the tropical cyclone making landfall on the southern part of Eastern China coast.The environmental features are compared between the tropical cyclones filling shortly after landfall and those surviving long after that.It is concluded that,for long-lived landfall tropical cyclones,there are weakening and eastward shrinking of the western North Pacific subtropical high,southward shifting of the westerly trough,long-lived low pressure circulation at low level,favorable thermo-dynamical condition at mid-and low-levels,sufficient water vapor transportation,meridional upper-level flow,strong Tibetan anti-cyclonic circulation,weak westerly jet,and strong low-level southeasterly jet.In such an environment,the whole level upward motion,upper-level divergence and low-level convergence can all be strong and sustain quite a long time,resulting in a long-lived tropical cyclone.And vice versa.