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 cal culate 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 t ide gauges showed that the averaged absolute differences between the simula ted 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 differenc es of the four tides are 6.88, 6.96, 5.96 and 6.16 degrees. The model repro duces well the tidal charts and this characteristic is discussed in detail. Comparison with 13 current stations, gave averaged absolute deviations bet ween the calculated and observed harmonic constant of the eastern and north ern 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 e llipse in the vertical are in fair agreement with the observations. The sur face distributions of the tidal current ellipse in the four tidal systems a nd the maximum current distributions are discussed in detail. (C) 2001 Ifre mer/CNRS/IRD/Editions scientifiques et medicales Elsevier SAS.