Development of Regional Framework for the Northwest Pacific Ocean Forecast System

Abstract

A regional framework for the Northwest Pacific ocean forecast system is presented as an application of GFDL Modular Ocean Model Version 4.1(MOM4p1) in a limited area domain. The open boundary condition, tidal mixing parameterization and data assimilation are considered. The openboundary problem is central to the successful limited area model. A robust open boundary condition has been introduced to the GFDL Modular OceanModel Version 4.1 (MOM4p1) by controlling the barotropic velocity. The Ensemble Optimal Interpolation has been implemented to assimilate SeaSurface Temperature, Sea Surface Height Anomaly (SSHA) and temperature/salinity profiles to the Northwest Pacific Regional Ocean ForecastingModel. In addition, the tidal mixing parameterization has been applied to the model. In the marginal seas of the Northwest Pacific, especially YellowSea and East China Sea, the tidal mixing is one of dominant oceanic processes. Without the tide, the numerical model could not capture the generalcirculation especially in summer. Conversely with the tide, it is not easy to handle the SSHA while assimilating it to the model. By applying the tidalmixing parameterization, the model resolves the tide-induced current as well as the SSHA has been directly assimilated. We present the oceanreanalysis which represents the general circulation and its variability in the Northwest Pacific region comparable to the observationata assimilation are considered. The openboundary problem is central to the successful limited area model. A robust open boundary condition has been introduced to the GFDL Modular OceanModel Version 4.1 (MOM4p1) by controlling the barotropic velocity. The Ensemble Optimal Interpolation has been implemented to assimilate SeaSurface Temperature, Sea Surface Height Anomaly (SSHA) and temperature/salinity profiles to the Northwest Pacific Regional Ocean ForecastingModel. In addition, the tidal mixing parameterization has been applied to the model. In the marginal seas of the Northwest Pacific, especially YellowSea and East China Sea, the tidal mixing is one of dominant oceanic processes. Without the tide, the numerical model could not capture the generalcirculation especially in summer. Conversely with the tide, it is not easy to handle the SSHA while assimilating it to the model. By applying the tidalmixing parameterization, the model resolves the tide-induced current as well as the SSHA has been directly assimilated. We present the oceanreanalysis which represents the general circulation and its variability in the Northwest Pacific region comparable to the observation