NUMERICAL SIMULATION OF CLOUD MICROPHYSICAL CHARACTERISTICS OF LANDFALL TYPHOON KROSA

In this study, the super typhoon KROSA (2007) was simulated using a mesoscale numerical model Global and Regional Assimilation and Prediction System (GRAPES) with a two-moment mixed-phase microphysics scheme. Local rainfall observations, radar and satellite data were also used to analyze the precipitation structure and microphysical features. It was shown that low-level jets and unstable temperature stratification provided this precipitation process with favorable weather condition. Heavy rainfall centers were located in the north and east part of KROSA with the maxima of 6-hourly total rainfall during the simulation more than 100 mm. The quantities of column solid water and column liquid water were generally equivalent, indicating the important role of ice phase in precipitation formation. Results of CloudSat showed that strong convection occurred in the eyewall around the cyclonic center. According to the simulation results, heavy precipitation in the northeast part of the typhoon was mainly triggered by convective clouds, accompanied by the strongest updraft under the melting level. In the southwest part of KROSA, precipitation intensity was rather homogeneous. The ascending center occurred in high-level cold clouds, favoring the formation and growth of ice particles.