多重解析度全球模式近台颱風模擬與比較：颱風路徑演變與強度快速發展之動力分析

The global model FV3GFS will shortly be used in operation at Central Weather Bureau, which was migrated from the FV3 used by NCEP operation at U.S. and now adaptively modified as TFV3 (Taiwan FV3). The major merit of the FV3 global model is on configuring six connecting cubes to represent the globe, thus allowing nested or stretched grids to increase resolution (currently up to 2 km at NCEP) on any cube for a local region. We have been able to apply high resolution FV3 (down to 7 km) with focus on Taiwan area to simulate long-term typhoon track before impingement as well as better capture the intense convection and rainfall associated with the typhoons over the Central Mountain Range. This project will aim to conduct high-resolution FV3 simulations and complete diagnostics of dynamics for typhoon systems (including potential vorticity, momentum and angular momentum and kinetic energy budget analyses) to understand essential features of typhoon track and convection as well as dynamic mechanisms of rapid intensification (RI) induced in the typhoon and its influence on track evolution. We will continue ongoing investigation on impinging Typhoon Lekima (2019) for the associated RI processes prior to track deflection and the influence of Taiwan topography and the induced RI on the track deflection, as well as on Typhoon Hagibis (2019) near Taiwan, which took a large earlier northward turning far away east of Taiwan but also associated with anoted RI. We will investigate the dynamic mechanisms of the track deflection and RI associated with Hagibis. We will apply both global models, FV3 and MPAS, for inter comparison on multi-resolution simulations of the two typhoon cases as well as the typhoons near Taiwan in 2021 with Taiwan-Area Heavy-rain Observation and Prediction Experiment (TAHOPE) field observations and FORMOSAT-7 radio occultation data for model assimilation and verification.