Tide Analysis and Prediction in the South China Sea

The tidal waves of the 16 tidal constituents (namely M-2, S-2, N-2, K-2, K-1, O-1, P-1, Q(1), MU2, NU2, T-2, L-2, 2N(2), J(1), M-1 and OO1) in the South China Sea from the global grid-point tidal harmonic constants of NAO. 99b are analyzed. Of the tidal constituents lacking of discussion in the previous studies, MU2, NU2, T-2, L-2, 2N(2) are less than 6cm in amplitude and similar as M-2 in propagation, J(1), M-1 and OO1 are less than 3cm in amplitude and similar as K-1 in propagation. The combination of the all sixteen tidal harmonic constants, the combination of eight tidal harmonic constants (M-2, S-2, N-2, K-2, K-1, O-1, P-1 and Q(1)) and the combination of four tidal harmonic constants (M-2, S-2, K-1 and O-1) are used to make the tide forecast models respectively. The contrasting of the tide forecasts and the tide tables of 41 stations shows that the combination of eight tidal harmonic constants makes the least error in tide forecast. In the Xisha Islands, the Nansha Islands, the Dongsha Islands and the east, west and south of the Hainan Island, the combination of eight tidal harmonic constants does well in tide forecast, their mean square errors are 9.1cm similar to 18.6cm.