关于闽南——台湾浅滩渔场上升流的研究

A STUDY OF UPWELLING OVER MINNAN-TAIWAN SHOAL FISHING GROUND

我们分析了闽南渔场水温、盐度、密度的分布规律,得出:自6月至翌年3月,闽南渔场存在着上升流。6月至9月上升流最强盛的位置在厦门——汕头海岸与台湾浅滩之间的海域(即图1加斜线的区域);10月至翌年3月则移至台湾浅滩西南外斜一带(即图8加斜线的区域)。这两支上升流的来源有所不同,前者来自南海下层水,后者可能来自黑潮下层水。我们还分析了闽南渔场底层常流,表层风生海流的规律。并从底层海流的爬升作用以及风生海流引起的海水涌升运动等动力学方面的因素出发,对闽南渔场上升流形成的可能机制及位置变动的原因作了进一步的阐述。最后,我们计算了上升流的速度,其量级为10-5米/秒。

Upwelling over the Minnan-Taiwan Shoal Fishing Ground has been found on the basis of the distribution of temperature,salinity and density.In summer,there is an upwelling center between the Xiamenzzz-Shantou Coast and the Taiwan Shoal.In this season,the upwelling results from the deep layer of the South China Sea.In autumn and winter,the upwelling center is in the Waixie Sea area(the continental slope under the southern part of the Strait).In these seasons,the upwelling is more probably the result of Kuroshio water coming from the deep layer.The reason for the generation and maintenance of the upwelling in this fishing ground has been explained on the basis of the effects of deep ocean currents moving towards the slopes in combination with the wind-driven currents.The upwelling speed has been computed as about 10-5m/sec.