太平洋大尺度环流数值模拟——Ⅱ:长期平均环流

NUMERICAL SIMULATION OF LARGE SCALE CIRCULATION IN THE PACIFIC OCEAN——II : ANNUAL MEAN CIRCULATION

用本文第Ⅰ部分所给出的四层太平洋环流模式,模拟在定常年平均大气强迫场驱动下太平洋长期平均环流。所进行的53年数值积分表明,模式成功地模拟出观测到的太平洋大尺度环流基本特征,特别是能直接计算出在海洋动力学和大尺度海气相互作用研究中有重要应用的海面起伏,对表层流场的模拟也明显优于具有同等分辨率的其他模式的结果;对气候有重要影响的SST形势的模拟结果同观测也较为一致。本文还用第53年数值积分资料进行了扰动压力场、斜压扰动压力场和海表热通量等的诊断计算和分析。文中还对模拟结果进行了物理和动力学的分析和解释。

The annual mean oceanic general circulation in the Pacific has been simulated by using the four-layer Pacific ocean general circulation model which was described in Part I of this study. Comparing with some available observational data the model proves to be capable of reproducing many of the large scale features of the Pacific circulation including the higher sea level regions in the Western Pacific; Surface current systems and the corresponding gyral structures; the tropical undercurrent and the equatoriward convergence in the subsurface layer; the stronger and narrower upwelling region in the Eastern Equatorial Pacific; the surface layer temperature distribution especially the warm water pool in the Western Pacific, and so on .In addition, the barotropic and baroclinic components of the perturbed pressure and the heat flux at the sea surface are computed and analysed, and some interpretations are given.