黄海西部海洋湍流的季节变化特征分析

SEASONAL VARIATION OF OCEAN TURBULENCE IN THE WESTERN YELLOW SEA

在2006—2007年开展的"中国近海海洋综合调查与评价"项目中,作者利用自由下降湍流剖面仪MSS60在南黄海海区分别进行了夏、冬、秋季三个航次的微尺度湍流观测,并计算分析了该海区的湍动能耗散系数ε,湍扩散系数κ等。通过与温度、流速分布图对比,结果表明三个季节的湍流混合趋势大体一致。在沿岸浅水区,混合作用比较强烈。而深水区湍流混合的垂直分布明显地表现出三层结构,混合较强的上混合层和底混合层,及相对较弱的中层。风混合和潮混合是黄海湍流混合的主要形式。风的影响主要表现在海洋上层,潮流的影响则表现于底层。

Using the data acquired with Microstructure Profiler MSS60 during the Comprehensive Survey and Evaluation in Chinese Nearshore Waters, turbulent kinetic energy dissipation rate and diffusivity in three seasons between 2006 and 2007 are estimated in the southern Yellow Sea. Our results reveal that mixing tends to be intensive in the coastal region where water is well-mixed. Away from the coast, mixing become more intensive in the near-surface and bottom layers than in the layers in-between. By combing the in situ observations, we suggest that mixing in the Yellow Sea is controlled by both tide and wind. Wind determines the strength of mixing in the upper layer, whereas tide mainly affects bottom mixing.