全球Stokes漂流的时空分布特征研究

Research on spatio-temporal characteristics of global Stokes drift in the ocean

利用海浪模式WWIII(Wave Watch III)2008年的模拟结果对海面Stokes漂流、Stokes输运、Stokes深度以及全球Langmuir数的年平均分布特征和季节平均分布特征分别进行了详细的研究与分析。结果表明,海面Stokes漂流和Stokes输运均呈现高纬度偏大的特征,以南极绕极流海域最为突出。全球大部分海域Stokes漂流影响深度在20 m以内,呈现大洋东部偏大,西部偏小的分布特征。全球大部分海域的混合作用是剪切不稳定性和Langmuir湍效应并存的状态,甚至有些海域是以Langmuir湍效应为主。因此,在进行大尺度的海洋数值模拟时,应该考虑波浪导致的混合效应。

In this paper, the annual and seasonal distribution characteristics of Global Stokes drift, Stokes transport, Stokes depth and Langmuir numbers were studied. The results show that the values of Stokes drift velocity and Stokes transport were larger in the high latitudes, especially in the area of Antarctic Circumpolar Current. Most Stokes depths were not deeper than 20 m, and the depths were deeper in eastern seas than those in western seas. The analysis of Langmuir numbers show that the classical turbulence （the turbulence that driven by the shear） and Langmuir turbulence occurred together in most of global oceans, while the Langmuir turbulence was dominant in some areas. Therefore, it is suggested that the effects of Stokes drift on mixing in the oceanic mixed layer are im-portant and should be taken into account in the parameterizations of ocean general circulation models.