Analysis Of Tropical Cyclogenesis In WNP And The Improvements In Potential Strength Mode

Studies have been shown that large-scale monsoon gyre activity is closely associated with tropical cyclogenesis over the western North Pacific. In this study, two cases of monsoon gyre activities in2002and2009are first examined. It is found that a monsoon gyre can be linked to the formation of one or more tropical cyclones, which usually occurs near or to the east of the gyre center. Further analysis of the monsoon gyre activity during the period2000-2009indicates that tropical cyclogenesis dominantly occurs near or to the east of the gyre center, although the definition of a monsoon gyre depends on its persistent time and the magnitude of its circulation. It is suggested that the tropical cyclogensis may be associated with the Rossby wave energy dispersion of monsoon gyres.During the process of improved the potential strength mode we considered the influence of relative vorticity, the middle and lower troposphere relative humidity and the inter-annual change of the subtropical high on tropical cyclogensis, the simulation results are more closer to the actual observation, but the generation of density distribution in the eastern Philippines are still less than ideal.