Evaluations for flow fields in a coastal reion with satellite-image analysis and numerical simulation

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Ocean currents such as the Kuroshio and Oyashio, which strongly influence on the flow fields around Japan-Island-China, are characterized by the mesoscale eddies with the representative horizontal length scale of a few hundreds kilometers. Although the behaviors of the mesoscale eddies are closely related with the coastal environments, there are a number of unknown factors for the dynamical evolution of the mesoscale eddies. On the other hand, the head investigator in this project has monitored the large-scale patterns of the water temperature and velocity vectors on sea surfaces with the image processing for the polar orbiting meteorological satellite NOAA, and then attempted to examine ocean current structures and the actual motion of mesoscale eddies around Japan-Island-Chain. For further evolutions of the above study, we here tried to develop an accurate tool to evaluate coastal currents with the satellite-image processing and numerical simulations. The main results of the project … More are expressed in the followings(1) Measurements for oceanic turbulence with the satellite-image analysisWe have conducted flow visualizations and sea-surface velocity measurements with NOAA/VHRR thermal infrared data. Every day the monitoring of the oceanic turbulence has been continuously performed by directly capturing the satellite data in our office. Combing the above satellite-based data and other published data concerning the oceanic turbulence, we have constructed the database for the oceanic turbulence around Japan-Island-Chain(2) Coastal current simulations with improved numerical modelsTo effectively incorporate offshore influences on coastal current simulations, a new one-waynesting procedure for coastal current model was developed and then applied to the coastal current simulation around an isolated island. Furthermore, we presented the two-way interactive nesting procedure to modify the above nesting model. We also attempted to improve the numerical accuracy of the 3D numerical models with special attentions to the hydrostatic approximation and sigma-coordinates Less