A NUMERICAL STUDY OF THE EFFECT OF TAIWAN ISLAND TERRAIN ON TYPHOON HAITANG (0505) TRACK
YU Zhen-shou 1, HOU Qiu-feng 2, WANG Hai-dong 1, WU Xian-du 1, LI Huai-chun 1 (1. Wenzhou Meteorological Bureau, Wenzhou 325027 China;2. Wenchen Meteorological Bureau, Wenchen 325300 China)
The track of Typhoon Haitang (0505), which passed through the Taiwan Island and landed again, has been successfully simulated by using the non-hydrostatic mesoscale atmospheric model MM5. Its structure is analyzed on the landing stage, and it is found that there exist good relationships between the typhoon abnormal moving track and its asymmetry structure. The effect of terrain of Taiwan Island on the typhoon Haitang, which made it rotate before landing and present a"V"type abnormal moving track in Taiwan straits, has also been simulated. Further analysis shows that the terrain of Taiwan Island not only directly affects the typhoon moving track, but also changes the typhoon track by affecting its asymmetric structure. Therefore, the typhoon asymmetric structure and the effect of terrain of Taiwan Island together results in the abnormal rotating track. The terrain of Taiwan Island tends to increase the SW-NE asymmetric structure of the typhoon and has different effect on SE-NW asymmetric structure during the landfall process of typhoon Haitang before entering and moving out of the Taiwan straits.