Scientists at Taiwan Typhoon and Flood Research Institute and National High Performance Computing Center have been improving and integrating the Purdue Atmospheric Models, Prof. Yeh’s hydrological models, and the ocean models into a comprehensive Earth Simulation System, which will be completed by the end of 2010; we have also been developing a new generation Earth Model for the coming six years.  Those models will be applied to predict typhoon, flooding, drought, weather, ocean current, regional climate change and hydrological cycle in Taiwan and Asia-Pacific. The models developed at Purdue University and in Taiwan, including the Purdue Regional Climate Model, non-hydrostatic models, turbulence-pollution model, characteristic-Lagrangian shallow water model, land-snow-vegetation model, etc.  The models were applied to study the lee-vortices in Taiwan and Rocky Mountains; dryline in the USA; 1988 drought; 1993 flood and several severe winter storms in the USA; 1998 Mei-Yu flood and dust storm in China and Korea; downslope wind and vortices in Whitesand Missile Range; pollution dispersion in Taiwan and O3 distribution in the USA; as well as the merge of the idealized typhoons, etc.  The comparisons with observations and other models will also be discussed.