Three dimensional simulation of tide and tidal current characteristics in the East China Sea

With the fine horizontal (5' x 5') and vertical (15 levels) grids, a three-dimensional model, imbedded a closure turbulence sub-model, was used to calculate the barotropic tides and tidal currents in the Bohai Sea, Yellow Sea, and East China Sea. The computational results are in good agreement with the observed M2, S2, K1 and O1 tides in the domain. Comparison with fifty tide gauges showed that the averaged absolute differences between the simulated and observed amplitudes are only 3.95, 2.96, 2.5 and 1.78 cm for the M2, S2, K1 and O1 tidal waves, respectively. The averaged phase-lag differences of the four tides are 6.88, 6.96, 5.96 and 6.16 degrees. The model reproduces well the tidal charts and this characteristic is discussed in detail. Comparison with 13 current stations, gave averaged absolute deviations between the calculated and observed harmonic constant of the eastern and northern tidal current of [6.53, 20.4, 7.55, 24.9]; [3.24, 24.2, 2.89, 22.8]; [2.98, 22.4, 3.6, 25.9]; [2.39, 35.8, 2.01 cm s(-1), 22.6 degrees] for M2, S2, K1 and O1, respectively. The calculated structures of the tidal current ellipse in the vertical are in fair agreement with the observations. The surface distributions of the tidal current ellipse in the four tidal systems and the maximum current distributions are discussed in detail. (C) 2001 Ifremer/CNRS/IRD/Editions scientifiques et medicales Elsevier SAS.