Using the center of figure method and center of mass method, precipitation and heavy precipitation processes caused by No. 9 typhoon ＂ Muifa＂ in 2011 were analyzed based on helicity, and the mechanism of typhoon rai...Using the center of figure method and center of mass method, precipitation and heavy precipitation processes caused by No. 9 typhoon ＂ Muifa＂ in 2011 were analyzed based on helicity, and the mechanism of typhoon rainfall was interpreted from the relation between helicity and ener- gy. The results showed that horizontal helicity checked the diffusion of nonlinear energy and maintained the development of the system. Precipitati- on mainly appeared on the southeast of vertical helicity, while heavy precipitation mainly occurred on its southwest. Compared with the center of fig- ure method, the center of mass method had good results, especially for heavy precipitation. Vertical helicity at 700 hPa reflected system deviation in rainfall regions well and had the best correction effect on rainfall intensity and regions展开更多
文摘Using the center of figure method and center of mass method, precipitation and heavy precipitation processes caused by No. 9 typhoon ＂ Muifa＂ in 2011 were analyzed based on helicity, and the mechanism of typhoon rainfall was interpreted from the relation between helicity and ener- gy. The results showed that horizontal helicity checked the diffusion of nonlinear energy and maintained the development of the system. Precipitati- on mainly appeared on the southeast of vertical helicity, while heavy precipitation mainly occurred on its southwest. Compared with the center of fig- ure method, the center of mass method had good results, especially for heavy precipitation. Vertical helicity at 700 hPa reflected system deviation in rainfall regions well and had the best correction effect on rainfall intensity and regions
