黄、东海域春季水团的划分、判别与分析

DISTINCTION, DISCRIMINATION AND ANALY-SIS OF WATER MASSES IN THE YELLOW SEA AND EAST CHINA SEA AREAS IN SPRING

本文对黄、东海邻接海域5—6月份的水团进行了划分和分析。水团的划分是用经过改进的逐步聚类分析法。对划分的结果,再用Bayes多组判别方法进行判别分析检验。证实所划出的11个水团,具有统计学要求的差异显著性,回代判别成效高达90％以上,说明划分是有实际意义的。这11个水团是:沿岸冲淡水(D),黄海表层水(Y),黄海底层冷水(YC),黄—东海混合水(YE),东海表层水(E),东海次表层水(EU),黑潮表层水(KS),黑潮次表层水(KU),黑潮次—中层混合水(KM),黑潮中层水(KI)和黑潮深层水(KD)。 用地理学和统计学的方法,对各水团进行了综合分析。给出了各水团特征的统计指标,讨论了它们的形成机制与分布变化特点。可将它们归并为三个水系:冲淡水系;混合水系和黑潮水系。对各水系、水团之间的相互关系进行了讨论,指出它们具有逐级变性的明显的规律性。

Water masses in the Yellow Sea and East China Sea areas in May to June are distinguished and analysed.An improved method of successive clustering is applied to distinguish water masses. The distinguished results are tested and verified by the method of Bayes multistage discrimination. It is proved that there is statistical obviousness of differences among the eleven water masses thus distinguished. An effective ratio of hindcast discrimination reaches more than 90 percent,which shows that the result is of practical significance. The eleven water masses are the Nearshore Diluted Water Mass (D), the Yellow Sea Surface Water Mass(Y), the Yellow Sea Bottom Cold Water Mass (YC), the Yellow Sea-East China Sea Mixed Water Mass (YE), the East China Sea Surface Water Mass(E), the East China Sea Subsurface Water Mass(EU ),the Kuroshio Surface Water Mass (KS), the Kuroshio Subsurface Water Mass(KU), the Kuroshio Subsurface-Intermediate Mixed Water Mass(KM), the Kuroshio Intermediate water Mass(KI) and the Kuroshio Deep Water Mass (KD).The water masses are analysed synthetically with geographical and statistical methods. For each water mass, the statistical characteristic indexes are given, the mechanism of its formation , and its distributional and varia-tional features are discussed. The water masses can be classified into three Water Systems, i. e, the Diluted Water System, the Mixed Water System and the Kuroshio Water System. Finally, the mutual relationships among the water systems and water masses are discussed and it is shown that there is an obvious regularity in their successive modifications.