a Numerical Model of the Kuroshio in the East China Sea.
A high resolution limited area model with realistic bottom topography has been developed for the East China Sea, based upon the primitive-equation GFDL ocean model. Solutions are obtained for an ocean driven by annual mean heat and fresh-water forcing at the surface, and specified advective transports of mass, heat, and salt at the open boundaries. Analysis of temperature and salinity on various isopycnal surfaces suggests that the mixing was confined to the surface layer, and that the entrainment of cooler and fresher coastal waters into the Kuroshio begins northeast of Taiwan. Analysis of fluid particle trajectories illustrates that the mixing in the East China Sea is attributable to the convergence of shelf water driven by Taiwan Strait outflow, and of subsurface Kuroshio water driven by shelf break upwelling. Also, the trajectory analysis suggested that a process of bifurcation is occurring southwest of Kyushu, and this process selects the fluid parcels that compose the Tsushima Warm Current. Further analysis showed that the dominant balance following a fluid parcel in the Kuroshio was between advection and horizontal diffusion. From this experiment a quantitative estimate of 0.085PW of heat transport, and 0.03Sv perthous of salt transport, representing 5% of the total Kuroshio transport of heat and salt, have crossed 33 ^circN into the Yellow and Japan Seas. In addition, as this warm and salty water is removed from the large-scale circulation, cooler and fresher coastal water of the order of 1Sv, blends into the Kuroshio as replacement.
- Pub Date:
- Physical Oceanography; Physics: Atmospheric Science