研究期間：10108~10207;Heavy rainfalls brought by landfalling typhoons often induce severe fresh floods and mudslides, causing bridge collapse and building breakdown, which result in tremendous economical and property damages. This proposal will investigate the precipitation physical processes of landfalling typhoons, by using the high-resolution WRF model simulations. The scientific issues are to understand how the Taiwan Central Mountain Range modifies the microphysical processes within the typhoon circulation and to investigate how the precipitation efficiencies within the inner core and outer rainbands are changed by the terrain effects. This project will choose Typhoon Morakot (2009) as the target typhoon case to investigate how the steep Taiwan topography modifies the microphysical processes by conducting the control and sensitivity simulations with the high-resolution WRF model. The essential microphysical processes responsible for the record-breaking extreme rainfall (more than 2700 mm in 3 days) will be examined. In addition, the project will conduct systematic comparisons between the single-moment (predicting only the mixing ratio) and two-moment microphysics schemes (predicting both the mixing ratio and the number concentration) for typhoon simulations. Through systematic comparisons and detailed analyses, this proposal is aimed to find out the optimal microphysics parameterization scheme which is most appropriate for the precipitation simulations of landfalling typhoons over the Taiwan area.
