子計畫：尺度交互作用對超高解析度全球模式模擬颱風氣候變遷之影響

The heavy rainfall associated with typhoon has strong impact on the total precipitation (drought and flood) over the East Asia and Taiwan region. Thus, the impact of large-scale circulation on the tropical cyclones activity under global warming has received considerable attention. However, the effect of interaction between tropical cyclones and the large-scale circulation on the simulation tropical cyclones (TC) activity in the climate models has less been investigated. In this study, HiRAM at 25 km and MRI at 20 km horizontal resolution are adopted to investigate the effect of scale-interaction on the simulation of TC in the models. A newly developed three-dimensional synoptic-scale eddy (SSE) kinetic energy equation by Tsou et al (2014) is adopted to analysis the energy conversion between TC, intraseasonal oscillation (ISO) and seasonal mean circulation. Our research shows that both the CKS-M (barotropic energy conversion between SSE and mean flow) and CKS-ISO (barotropic energy conversion between SSE and ISO) simulated in High Resolution Models are coincided with the main TC genesis region. TC number projected to decrease over the western North Pacific is mainly contributed by the reduction of the CKS-M at the end of 21st century. CKS-M is projected to significantly reduce due to the weakening of the monsoon trough and the zonal wind convergence. Thus, the mean circulation will provide less energy to SSE in the future. The detailed SSE energy may help us to understand the energy source of typhoons and improve the climate simulation of typhoon activities over the western North Pacific.