冬季寒潮期间黄、渤海水位低频波动研究

THE LOW-FREQUENCY SEA LEVEL FLUCTUATIONS IN THE YELLOW SEA AND THE BOHAI SEA DURING A WINTER STORM

利用POM(Princeton Ocean Model)海洋数值模式建立渤、黄、东海冬季三维环流动力学区域模型。模型在海-气边界使用包括风应力、气压和热通量的大气驱动,海洋边界使用西太平洋模式提供的环流和潮位驱动,综合模拟潮波运动、温度、盐度、环流变化和水位低频波动。模拟了2001年1月寒潮过境时黄、渤海水位低频波动及流场变化,分析了其对大风过程、气压、降温的响应,发现冬季强劲的北风和西北风都可以通过抽吸振荡在渤、黄海诱发水位的低频波动,东北风则由于地形影响不能诱发渤、黄海的低频波动。气压和降温只是在波动幅度上有一定的影响。波动发源于渤海和北黄海,最大波幅可以达到0.6m。波动进入南黄海后有沿黄海深槽西侧传播的倾向,波动幅度在传播过程中逐渐减小。

A three-dimensional numerical model was developed based the Princeton Ocean Model （POM） to study circulations in the East Sea, Yellow Sea and Bohai Sea in a wintertime period. The model was forced by wind, air pressure and heat flux at the air-sea interface, and current and tidal elevation at the open boundary were provided by a larger model based on the entire West Pacific Ocean. This hydrodynamic model was used to investigate tide, salinity, temperature, circulation and the low-frequency sea level fluctuations. This study explored the response of the low-frequency sea-level fluctuations and the current filed to the winter storm occurred in the Yellow Sea and the Bohai Sea during January 2001. The results showed that the pumping and vibrating of the north wind and northwest wind caused the low-frequency fluctuations during the winter storm, while the easterly wind failed to lead to this phenomenon due to topography limitations. Both air pressure and temperature decrease only caused changes in the fluctuation amplitude. Furthermore, the fluctuations originated in the Bohai Sea and the north Yellow Sea. The peak of the fluctuation amplitude reached as high as 0.6m. The fluctuations propagated along the west of the Yellow Sea Trough after entering the south Yellow Sea, with the amplitude decreasing along the route of the propagation.