SEA-SURFACE HEIGHT VARIATIONS IN THE YELLOW AND EAST CHINA SEAS - 2 -SSH VARIABILITY IN THE WEEKLY AND SEMIWEEKLY BANDS

Two types of models are used to examine the sea surface height (SSH) v ariability at the principle short time frequency bands in the Yellow a nd East China Seas. The models are a primitive equation numerical mode l and a statistical model based on TOPEX/POSEIDON altimeter data. In s itu pressure gauge measurements at two mooring locations are first use d to evaluate each model. In addition, a comparison of the numerical a nd statistical models is made through duplicate analysis of the respon se to the main extended empirical orthogonal function wind stress mode s. In the northern Yellow Sea the wind stress, pressure gauge data, nu merical model, and statistical model all indicate local spectral maxim a in bands centered on the weekly and semiweekly periods. The coherenc e of the two models with the in situ data is significant down to 3-day periods at the northern mooring and down to 5-day periods at the sout hern mooring. The meridional wind stress variability in the semiweekly band is higher than the weekly band energy in the northern Yellow Sea and Bohai Bay and lower than the weekly band energy across the East C hina Sea. The SSH variability contained in the weekly and semiweekly b ands is largest in the Bohai Bay and northern Yellow Sea with a region of high energy along the Chinese coast. The spatial structure of the weekly and semiweekly SSH variability is similar to the wind stress va riability at these bands with semiweekly variability higher in the Boh ai Bay and northern Yellow Sea and weekly variability dominant in the East China Sea.