舟山渔场及其邻近海域水团的气候学分析

CLIMATOLOGICAL ANALYSIS OF WATER MASSES IN ZHOUSHAN FISHING GROUND AND ADJACENT REGION

根据多年 (1 95 8— 1 990 )月平均温、盐度资料 ,采用模糊聚类分析法划分了舟山渔场及其邻近海域的水团 ,并对该海域水团的配置、主要特性及其季节变异特征进行了气候学分析。结果表明 ,舟山渔场及其邻近海域共存在 4个水团 ,即江浙沿岸水、台湾暖流表层水、台湾暖流深层水和黄海混合水 ;全年水团的配置可归纳为冬季型、夏季型和过渡型 3种类型 ;江浙沿岸水的主要特征为低盐 ,其分布范围和盐度的季节变化与长江入海径流密切相关 ,而温度的季节变化则主要受太阳辐射的影响 ;台湾暖流表层水具有高温、次高盐特征 ,其北伸程度和温、盐特性均具有明显的季节变化 ,即冬季北伸强、温度低、盐度高 ,夏季北伸弱、温度高、盐度低 ;台湾暖流深层水以低温、高盐为主要特征 ,仅存在于 4— 9月 ,其温、盐性质较稳定 ;

In this paper, based on multi year (1958—1990)monthly mean temperature and salinity values, water masses in the Zhoushan fishing ground and adjacent region were divided using fuzzy clustering analysis The distributions, major properties and seasonal changes of the water masses in this area were analyzed The results showed that in total there are four water masses in this area, namely, Jiangsu Zhejiang Coastal Water (JCW),Taiwan Warm Current Surface Water (TWCSW), Taiwan Warm Current Deep Water (TWCDW) and Huanghai (Yellow) Sea Mixing Water The JCW and the TWCSW are the major water masses The JCW is characterized by low salinity and has distinct seasonal changes in distribution and themohaline properties The seasonal changes in its salinity and distribution are closely related to the Changjiang (Yangtze) River runoff The temperature change, however, in the JCW is mainly affected by solar radiation The TWCSW is characterized by high temperature and the second highest salinity Its northward extension and thermohaline properties all have clear seasonal changes. In the winter, the northern limits move northward to a higher latitude, the temperatures are lower and the salinity is higher In summer, the northern limits move to a lower latitude, the temperatures increase and the salinity reduces The TWCDW,which exists only from April and sepember is characterized by both low temperature and high salinity The Huanghai (Yellow) Sea Mixing water's main body was outside the current research region