中文摘要：

利用1987到2011年期间7个航次的调查数据揭示了夏季钓鱼岛东北海域存在冷涡的事实,首次将其命名为钓鱼岛东北冷涡,并初步分析了钓鱼岛东北冷涡特征及其生长消亡规律。结果表明：钓鱼岛东北冷涡是由底层海水涌升形成的中尺度冷涡,但其凸起的温盐等值线不能在海表面露头,不能从海表层水文特征识别该涡;该涡尺度在150km左右,其水团特征盐度为34.70—34.80,特征温度低于20°C;该涡是季节性冷涡,每年夏季都会出现,该涡5、6月份开始形成,到8月份强度最强,此时其向上涌升的趋势可以达到水深30m以浅,然后开始减弱,可以持续到10月份左右,其它时间则不存在;从50m层的温盐特征来看,不同年份夏季冷涡核心位置稍有不同,整体位置在123.2—124.2°E,26—27°N的范围内。

英文摘要：

CTD data obtained in seven cruises from 1987 to 2011 were used to analyze the characteristic and seasonal variation of a vortex northeast of the Diaoyu Island, East China Sea. Results show that the vortex, about 150 km in scale, is a mesoscale cold vortex formed by upwelling of bottom water. The characteristic salinity is 34.70—34.80 and temperature 20°C. It is a seasonal vortex and occurs every summer, initiates in May or June, summits in August by reaching up to 30 m below surface, and disappears in around October. The thickness of thermocline is about 20 m, and the temperature gradient could reach 0.5°C/m. Shown in the distributions of salinity and temperature at 50 m depth, the position of the vortex cores can be located in 123.2—124.2°E, 26—27°N, and may slightly shift in different years.