渤海的风和温度层结有明显的季节变化,因而其环流与输运亦有明显的季节信号.以季节平均的海面气象条件和开边界的潮波系统驱动三维斜压水动力模型--HAMSOM,模拟了渤海冬、夏季的总环流.渤海环流冬强夏弱,表层风漂流常被下层逆风流所补偿.深度平均环流,即水柱内的输运,流型有显著的季节变化:冬季在渤海中部沿逆时针方向旋转,辽东湾顶有一个顺时针流涡,阻碍了湾顶水与外海水的交换;夏季则为一个大的贴岸的顺时针流环,内嵌许多局地涡旋.这些与渤黄东海海洋水文图集中给出的多年观测的环流基本相同,同时也被水文要素分布及耐盐浮游动物的出现所佐证.风的季节变化决定了渤海大部分海区、特别是海峡附近环流的季节变化,但辽东湾东岸众多的岬角涡旋却不随季节变化,因为它们是由潮波系统与岬角岸型变化的非线性相互作用产生的.%The forcing factors of the circulation in the Bohai Sea, such as wind and stratification, have obvious seasonal variations. The circulation system and transport should vary accordingly. By using the three-dimensional baroclinic model--HAMSOM, driven by the seasonal mean meteorological data above the sea surface and tides at the open boundary, the general circulations in summer and in winter are calculated. Surface wind drift current is often compensated by the current in the lower layer. For the depth-averaged circulation, there are a large counterclockwise gyre in the central area and a clockwise gyre at the top of the Liaodong Bay in winter while a clockwise gyre with many local eddies in summer. These are consistent with the observations. Wind dominates the seasonal variations except the local eddies in the east of Liaodong Bay, which are induced by the tidal nonlinear interaction near the headlands.
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