北黄海潮流、余流垂直结构及其季节变化

The Vertical Structure and Seasonal Variation of the Tide Current and Residual Current in the North Yellow Sea

基于对2006年夏季与2007年冬季在123.51°E,38.00°N的各1个月潮流和水位观测数据的分析,发现夏季余流呈现两层结构,上层流向为西北,下层流向东南,并且当大潮日期附近,在跃层附近深度存在若干流速较强的水层;冬季余流除了个别层以外基本上均为西北向流入北黄海,从中可以看到风场改变所引发的异常增减水和强流出现。对潮流椭圆的分析表明,半日潮族分潮流的最大流向自夏季至冬季存在着顺时针的旋转,旋转角大约为16(°)～18(°),并且夏季半日潮族随深度顺时针,全日潮族逆时针旋转,而冬季基本上上下一致。

Analysis of tidal current and sea level has made based on the observations during the summer in 2006and the winter in 2007,respectively.The result indicates that a two-layer structure of residual current exists in the summer,with its upper layer northwestward and lower layer reversed.In addition,some strong residual occurs nearby the pycnocline during astronomical tide;In winter,the entire residual directed to northwestward,with abnormal sea-level fluctuation and associated current.Analysis of tidal ellipse indicates that in summer the semi-diurnal component rotates clockwisely with depth while for diurnal component counterclockwisely.But in winter the vertical structure is almost homogeneous.Moreover,a clockwise rotation exists for the direction of semi-diurnal component from summer to winter,with a angle of 16（°）-18（°）.