Development and Verification of the Taiwan Ocean Prediction System

Taiwan is an island state surrounded by the sea to which the economic activity and the ecological environment are closely related. The aim of the Taiwan ocean prediction system is to satisfy the assessment of the marine environment and the reduction of risks in the coastal zone of Taiwan. The high-resolution wave and ocean numerical models, the data assimilation and the observing database are established and operated by Taiwan Ocean Research Institute (TORI). In order to reduce computational time and increase the grid resolution, the one-way nested grids are adopted for Northwestern Pacific Ocean and the sea around Taiwan. The WAVEWACTCH-III and the nested SWAN wave models and the multi-scales Princeton Ocean Model (POM) are respectively used for the predictions of the wind wave and the three-dimensional ocean current. A joint effect composed of the tide and the ocean circulation is also taken into consideration for resolving the complex current field around Taiwan. The performance evaluations are well carried out to investigate the rationality of the numerical models by using the observed data, such as temperature and current velocity profile, wave height and wave period of data buoys and sea surface current of the TORI high frequency radar observing system. The well verified results of the numerical ocean model assimilated by the sea surface height are used to investigate characteristics of Kuroshio in the waters off eastern Taiwan, and several value-added modules, such as storm surge simulation and particle tracking, are also developed to apply to the maritime casualty search and rescue, the hazard mitigation and the disaster assistance.