| During 1999-2000, 13 bottom mounted ADCPs and 12 wave/tide gauges were deployed along two lines across the Korea/Tsushima Strait, providing long-term measurements of currents and bottom pressure. Tidally analyzed velocity and pressure data from the moorings are used in conjunction with coastal tide gauge measurements in a linear barotropic data assimilation model. An additional data set comprised of other moored ADCPs and altimeter measurements are used for validation and then for assimilation into the model. The model fits vertically averaged data to the linear shallow water equations in a least-squares sense by adjusting the incoming gravity waves along the boundaries. Model predictions are made for the M2, S2, K1, O1, N2, P1, K2, and MU2 tides. The average rms error between the observations and predictions of tidal velocity components is 1.5 cm/s. The average rms error between the observations and predictions of tidal surface height is 3 cm for the moored tide gauge sites, 4 cm for the altimeter sites, and 6 cm for the coastal tide stations. An extensive error analysis was performed. The expected errors in the barotropic tide measurements were calculated and then these errors were propagated through the descritized shallow water equations, yielding predictions for the expected levels of data/model mismatch. The actual levels of data/model mismatch exceed these predictions and thus indicate model inadequacies, which may include errors in bathymetry and coastlines. These analyses are then used to calculate error maps based on measurement errors and on estimated model deficiencies. |
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