高频地波雷达观测的苏北辐射沙洲南部海域夏季表层海流特征

Summertime surface current characteristics in the southern region of Subei radial sand ridges detected by HF surface wave radar

本文利用高频地波雷达获得的江苏如东海域大范围长期海流观测资料对苏北辐射沙洲南部烂沙洋海域夏季表层海流特征进行了分析。分析结果表明:研究海域表层海流靠近近岸一侧为往复流,流向总体上呈西北-东南向,靠近外海一侧为旋转流;海域潮流动力较为强劲,夏季表层海流实测最大流速达1.47 m/s,涨潮平均流速介于0.44～0.55 m/s,落潮平均流速介于0.38～0.52 m/s,海域西北部区域涨落潮平均流速明显大于其他区域;表层潮流为正规半日潮流,M_2分潮为最主要分潮,其潮流椭圆长轴范围为0.57～0.71 m/s,远大于其他分潮,其次为S_2分潮;该海域夏季表层余流呈现近岸大离岸小的分布趋势,余流流向基本指向近岸方向,从离岸到近岸余流流向呈现逆时针偏转。

Using long-term ocean observation data obtained by HF surface wave radar,the summertime sea surface currents and residual currents characteristics in the Lanshayang sea area of radial sand ridges in the northern Jiangsu Province are analysed in this paper.Results show that,the surface current near the coast is reciprocating,and the direction is generally from northwest to southeast,while the offshore side is rotational.The maximum surface velocity in summer can reach 1.47 m/s so that tidal energy is strong in here.The average flood current velocity is between 0.44 m/s and 0.55 m/s and the average ebb current velocity is between 0.38 m/s and 0.52 m/s.The average velocity in the northwest of the sea area is obviously larger than that of other areas.The surface current is regular semidiurnal tidal current and M 2 is the most important constituent,followed by S 2.The major axis of M 2 tidal current ellipses is between 0.57 m/s and 0.71 m/s,greater than other constituent.The surface residual current velocity is larger in inshore than in offshore,and the direction is generally toward the coast.From offshore to inshore,residual current direction exhibits an anticlockwise deflection.