基于HYCOM的南海中尺度涡数值模拟

发布时间：2018-03-07 08:51

本文选题：中尺度涡　切入点：数值模拟　出处：《海洋通报》2016年03期 　论文类型：期刊论文

【摘要】：结合AVISO(Archiving Validation and Interpolation of Satellite Oceanographic Data)高度计资料,利用改进的NERSCHYCOM(Nansen Environmental and Remote Sensing Center-Hybrid Coordinate Ocean Model)大洋环流模式,对南海中尺度涡进行数值模拟研究,主要包括中尺度涡的三维结构、南海EKE(Eddy Kinetic Energy,涡动动能)的垂向变化、黑潮中尺度涡的脱落以及涡旋近岸时的结构变化等。模式再现了2007年2月-3月菲律宾西侧海域的一次暖涡过程,探究了其生命期中各阶段的特征物理量的变化,对其成熟时期的涡旋结构研究表明,中尺度涡的结构呈现不对称性,涡旋两侧的流场空间范围和流场强度均不相同,涡旋的半径和中心位置随深度不断变化,并且由涡旋作用产生的升降流的中心与涡旋自身中心并不重合,二者之间有一定距离。初步探索EKE的垂向分布情况,认为南海年平均EKE在垂向变化上呈现三段式,主要部分分布在300m以浅深度,但同时垂向又能达到海洋深层。分析了一次黑潮中尺度涡脱落的模式模拟个例,推测黑潮中尺度涡脱落原因:黑潮流径西移、外海中尺度涡对黑潮的强迫、地形作用,并且结果表明从黑潮脱落的中尺度涡可以携带大量高温高盐水体进入南海,对南海的温盐性质产生很大的影响。初步探索涡旋近岸时的结构变化,涡旋靠近岸界时,受岸界挤压,流速在一段时间内会增大,继续靠近岸界,由于岸界的摩擦、海底的拖曳,导致能量耗散,流速减小,最终涡旋消亡。
[Abstract]:Based on the AVISO(Archiving Validation and Interpolation of Satellite Oceanographic data, using the improved NERSCHYCOM(Nansen Environmental and Remote Sensing Center-Hybrid Coordinate Ocean Model, the mesoscale vortices in the South China Sea are numerically simulated, including the three-dimensional structure of the mesoscale vortices. The vertical variation of EKE(Eddy Kinetic energy in the South China Sea, the shedding of mesoscale vortices in the Kuroshio and the structural changes of vortices near the coast of the South China Sea. The model reproduces a warm vortex process in the western Philippines from February 2007 to March. In this paper, the variation of characteristic physical quantities in each stage of its life cycle is studied. It is found that the structure of mesoscale vortices is asymmetrical, and the spatial range and intensity of flow field on both sides of vortex are different. The radius and central position of the vortex vary with the depth, and the center of the ascending flow generated by the vortex does not coincide with the center of the vortex itself, and there is a certain distance between the two. The vertical distribution of EKE is preliminarily investigated. It is considered that the annual average EKE in the South China Sea presents a three-section pattern in vertical variation, mainly distributed in a shallow depth of 300m, but at the same time it can reach the deep ocean depth. An example of model simulation of mesoscale vortex shedding in the Kuroshio is analyzed. The causes of mesoscale vortex shedding in the Kuroshio are as follows: the Kuroshio moving westward, the forcing of mesoscale vortex on the Kuroshio, the topographic action, and the results show that the mesoscale vortex from Kuroshio shedding can carry a large amount of high temperature and high salt water into the South China Sea. It has a great influence on the characteristics of temperature and salt in the South China Sea. The structural changes of the vortex near the shore are preliminarily explored. When the vortex is near the shore boundary, the velocity of velocity will increase in a period of time when the vortex is close to the shore boundary, and the velocity will continue to be close to the shore boundary because of the friction of the shore boundary. The drag of the seafloor results in energy dissipation, a decrease in the velocity of velocity, and the eventual extinction of the vortex.
【作者单位】：解放军理工大学气象海洋学院;中国卫星海上测控部;
【基金】：国家自然科学基金(41306010)
【分类号】：P731.2

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