中文摘要：

采用三维斜压非线性数值模式并结合卫星遥感资料分析，对南海北部陆架区夏季上升流进行了初步研究。研究结果表明，上升流是南海北部陆架区69月的一个规律性现象，而不是个别年份的特殊现象；海南岛东部沿岸及雷州半岛以东广州湾东南部-带海域（琼东上升流区）、汕头沿岸直至福建沿岸南日群岛附近海域（粤东上升流区）夏季表层及次表层海水均表现出明显的低温、高盐、高密等陆架上升流特征；上升流中心主要位于海南岛以东清澜湾至七洲列岛之间111°10′E、19°45′N附近，陵水湾至陵水沿岸110°15′E、18°25′N附近，粤东汕头沿岸116°45′E、22°50′N附近及澎湖列岛以西118°E、23°40′N附近。同时通过对模拟结果与QuikSCAT风场的比较分析发现，沿岸上升流与局地风场有着密切的关系，夏季西南风及风应力旋度对琼东沿岸上升流的形成有着非常积极的作用；而粤东沿岸风应力旋度较小，但夏季西南风仍是诱生粤东沿岸上升流的重要因素之一。

英文摘要：

Summer upwelling system over the northern continental shelf of the South China Sea is investigated with a three-dimensional baroclinic nonlinear numerical model forced by QuikSCAT winds. The modeling results show that the summer upwelling is a regular phenomenon during June-September in the area. The surface and subsurface water represent obvious continental shelf upwelling characteristics, such as low temperature, high salinity and high potential density in the east of the Hainan Island, the east of the Leizhou Peninsula and the southeast of the Zhangjiang Bay （the upwelling areas in the east of Hainan Island）, and the inshore areas from the Shantou Coast to the Nanri Islands of Fujian province （the upwelling areas in the eastern Guangdong）. The centers of the upwelling are mostly located at 111°10′E, 19° 45′N between the Qinglan Bay and the Qizhou Archipelago of eastern Hainan Island, at 110°15′E, 18°25′N between the Lingshui Bay and Lingshui coast, at 116°45′E, 22°50′N of the Shantou inshore and at 118°E, 23°40′N of western Penghu Archipelago. The climatic satellite remote sensing data （AVHRR SST） also shows that the existence of summer upwelling over the northern continental shelf of the South China Sea, and the upwelling areas and centers are consistent very well with the modeling results. At the same time, the QuikSCAT winds are compared with an upwelling index, which indicates that the coastal upwelling has a close relationship with local wind fields. The southwest winds and wind stress curl during summer play very positive roles in inducing the coastal upwelling in the east of Hainan Island. Whereas the wind stress curl in the east of Guangdong inshore shows a little smaller during summer, the southwest wind is also one of the most important factors inducing the summer coastal upwelling in the east of Guangdong inshore.