Multimodal Internal Waves Generated over a Subcritical Ridge: Impact of the Upper-Ocean Stratification
Multimodal Internal Waves Generated over a Subcritical Ridge: Impact of the Upper-Ocean Stratification
复制标题
亚临界海脊上产生的多模态内波：上层海洋分层的影响
DOI：
10.1175/jpo-d-14-0132.1
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发表时间：
2015
影响因子：
3.5
通讯作者：
Jay David A.
中科院分区：
文献类型：
--
作者：
Xie Jieshuo;Pan Jiayi;Jay David A.
正压潮汐与次表层地形的相互作用对海洋混合是至关重要的。然而，能够引起强混合的大幅度、非线性、内孤立波(ISW)的行为仍然知之甚少，尤其是高模和多模内波。为此，发展了一个垂直分辨率可调的2.5维非静力模式，以研究上层海洋层结对潮汐诱导的多峰内波的影响，并说明它们是如何由只存在向上传播的内波束(IWB)的亚临界脊线产生的。基于模型结果，研究了层结对激发IWB性质和特性的影响，以及对辐射模式1和模式2内波能量分配的影响。次临界地形也能有效地在环流中产生高模内波，且高模对环流的贡献随着上层海平面高度的增加而增大。
AbstractInteraction of barotropic tides with subsurface topography is vital to ocean mixing. Yet the behavior of large-amplitude, nonlinear, internal solitary waves (ISWs) that can cause strong mixing remains poorly understood, especially that of higher-mode and multimodal internal waves. Therefore, a 2.5-dimensional, nonhydrostatic model with adjustable vertical resolution was developed to investigate effects of upper-ocean stratification on tidally induced multimodal internal waves and to show how they are generated by the subcritical ridge where only upward-propagating internal wave beams (IWBs) are present. The effects of the stratification on properties and characteristics of the excited IWBs and on the energy partition of the radiated mode-1 and mode-2 internal waves were investigated based on the model results. Higher modes of internal waves can also be effectively generated in the IWBs by the subcritical topography, and the contribution to IWBs from higher modes increases with the upper-ocean stra...