Diagnose and Research on Typhoon Disasters Caused by 0505 Typhoon Haitang

The 0505 Typhoon Haitang has extensive confines, strong intensity ,intricate trace and different characteristics in its different stages. It caused very severe damage breakage and grave loss in China. Based on the analysis on the typhoon disasters and general circulation, this paper researches the basic reasons of heavy rain in Zhejing and Fujian provinces by using diagnosing methods such as Q vector and helicity, etc. The helicoidal cloud cinctures within typhoon's periphery, close-grained cloud cinctures near its center caused heavy rain in Taiwan and southeastern China. And cloud agglomerates existing in the southeast jet in its periphery also made strong precipitation. Furthermore, the interaction between the typhoon's remnant low-pressure and the west wind systems brings strong convective weather phenomena and heavy precipitation in northern China. In the fore-and-aft typhoon landfalling, the convergence or divergence of Q vector can be used to estimate vertical motion field. Moreover, the typhoon's helicoidal cloud cinctures behaved as a positive maximum center on the lower level relative helicity field by means of analyzing the helicity.