Based on the CTD data observed during the 908 program, the distributions and seasonal changes of water temperature in the Bohai Sea, the Yellow Sea and the East China Sea are analyzed systematically. The results reveal that in winter the structure of water temperature shows horizontally many tongue-shapes, of which the warm water tongues occur mostly in the offshore area, while in the inshore area the i-sotherms are basically parallel to the coastline, with some cold water tongues directing to the south and strong temperature fronts occurring between the warm and the cold waters. In summer, various cold water masses or blocks with different characters appear at the bottoms of the Bohai Sea, the Yellow Sea and the East China Sea, of which the most typical ones are "the Middle Bohai Sea Cold Water", the "Liaodong Bay Cold Water", the "Yellow Sea Cold Water Mass", the "Qingdao Cold Water Mass" and the "Bottom Cold Water Mass" in the Northern East China Sea. In spring and autumn, the distributions of water temperature display a transitional nature. In spring, thermocline emerges and cold water masses such as the Middle Bohai Sea Cold Water and the Yellow Sea Cold Water Mass begin to come up. When autumn comes, the thermocline submerges and finally disappears and the distributions of water temperature tend gradually to become uniform vertically. Moreover, the results also reveal that regional variations of water temperature are present in the three seas, and that the annual variation amplitude of water temperature distributions tends to decrease both from north to south and from the inshore to the offshore.%利用“908”专项所获取的CTD观测资料,系统地阐述了渤、黄、东海温度的分布特征及季节变化.结果显示,冬季,水平方向上,水温分布呈现多舌状:外海温度多暖舌结构,近岸等温线基本平行于岸线,并出现多个指向南方的冷水舌,且暖流区与近岸冷水区间形成了较强的温度峰.夏季,三大海域底层均出现了各具特色的冷水团和冷水块,最为典型的有“渤中冷水”、“辽东湾冷水”、黄海冷水团、青岛冷水团和东海北部底层冷水.春、秋季水温分布呈现过渡季节的特征.春季,跃层开始出现,“渤中冷水”及黄海冷水团等冷水现象开始形成.进入秋季,跃层明显下沉,直至消失,水温分布逐渐呈现垂向均匀状况.同时,分析还表明,三大海域的水温分布存在明显的区域性差异.水温分布的年变幅从北向南、从近岸向外海递减.
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