黄海,渤海底层盐度预报方法的研究

A Study on the Method of Predicting Bottom Salinity in the Bohai and Yellow Seas

根据二维流体动力学方程和深度平均盐度扩散方程在河口径流量以及蒸发和降水之差为已知情况下构成的闭合方程组，预报出深度平均盐度，然后利用底层盐度与度平均盐度、水深和时间之间的经验关系，给出底层盐度的二维预报。

Under conditions of the known estuarine runoff and difference between precipitation and evaporation, the depth-averaged salinity distribution is predicted by solving the closed equation system conanting of two-dimensional hydrodynamic equations and a depth-averaged salinity diffusion equation. A two-dimensional forecast of the bottom salinity is then made by using the empirical relationships between the bottom salinity and depth-averased salinity, water depth and take(month). In order to verify the reliability of the trial prediction, the calculated results of the bottom salinity in the Bobal and Huanghai Seas(July 11 of 1979, the Period of validity in prediction was about 3 days) were compared with the observed data(July 11 of 1979, at 104 stations west of 124. 5°E) obtained from a periodical hydrographic survey. The comparison Showed that the correlation coefficient(R) between the trial prediction result and the observed value was 0. 96 and the root-mean-square error(a) was 0. 26. The number of the stations where the absolute errors calculated were less than 0. 2 and 0. 3 accounted for 63. 5 % and 77. 0% of the total number of stations, respectively, and the total mean absolute error was 0. 19. Therefore, the resultS of the trial prediction are satisfactory.