海南岛东北海域海流和余流特征分析

Characteristics Analysis of Current and Residual Current in the Northeastern Sea Area of Hainan Island

关键词:  海流  余流  调和分析

Key words:  currents  residual currents  harmonic analysis

摘要:

[目的]研究海南岛东北海域的潮流、余流特征和分布规律。[方法]依据2017年6月在海南岛东北海域调查的夏季大潮实测海流数据,采用准调和分析方法分析实测数据,并根据该分析所得的一些参数分析研究区域的潮流性质、潮流运动形式、M₂分潮潮流椭圆、潮流的垂直分布及夏季的余流分布。[结果]海南岛东北海域的潮流以不正规半日潮流为主;各站点潮流椭圆旋转率都较小,潮流运动形式以往复流为主,方向为NW-SE;除S4站以外,其余各站海流均为略带旋转的往复流,往复流的方向为NW-SE,旋转流的旋转方向为顺时针;研究海域表层余流大于中底层,近岸余流较弱,琼州海峡附近的站点余流最强;各站表、中、底层余流流向较一致,表层余流主要受风场的影响作用,底层余流主要受到底地形的影响。[结论]对调查区域的潮流、余流特性有了一个较为全面的认识。

Abstract:

[Objective] To analysis the characteristics and distribution law of the tidal current and residual current in the northeastern sea area of Hainan Island.[Methods] Based on the summer tide data measured in the northeastern sea area of Hainan Island in June 2017, the quasi-harmonic analysis method was used to analyze the measured data, and according to some parameters obtained from the analysis, the tidal nature of the research area, the form of tidal movement, the ellipse of the M₂ tidal current, the vertical distribution of the tidal current and the residual current distribution in summer were analyzed.[Results] The irregular semi-diurnal tidal current was the main tidal current in the northeastern sea area of Hainan Island.The elliptical rotation rate of tidal current at each station was small, and the tidal current movement was mainly in the form of reciprocating current in the past with the direction of NW-SE. Except for the station S4, the reciprocating currents at other stations were all slightly rotating reciprocating currents, the direction of reciprocating current was NW-SE, and the rotation direction of the rotating current was clockwise. The surface residual current was larger than the middle and bottom layer, the near-shore residual current was weaker, and the station residual current near the Qiongzhou Strait was the strongest. The surface residual current was mainly affected by the wind field, and the bottom residual current was mainly affected by the bottom topography.[Conclusion] With these results, we have a more comprehensive understanding of the trend and residual characteristics in the investigation sea area.