Assessing the west ridge of Luzon Strait as an internal wave mediator
Assessing the west ridge of Luzon Strait as an internal wave mediator
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DOI：
10.1007/s10872-007-0076-8
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发表时间：
2007-12
影响因子：
2.3
通讯作者：
S. Chao;D. Ko;R. Lien;P. Shaw
中科院分区：
文献类型：
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作者：
S. Chao;D. Ko;R. Lien;P. Shaw
吕宋海峡在深处被两个经向脊阻挡，东脊略高于海峡中游的西脊。以前的数值模式认为吕宋海峡是进入南中国海北部的M2内潮的主要发生地(日本和日本，2004年)，但西向与东向脊线的作用尚不确定。我们使用南中国海北部的静力模式和一个非静力的、面向过程的模式来评估吕宋海峡西脊如何改变内潮、内孔和内孤立波的西向传播。西脊的动力作用强烈地依赖于内波的特征，并且在空间上是不均匀的。对于M2潮汐，两个模型都将吕宋海峡中游的西脊确定为来自东脊的内波的阻尼器。在吕宋海峡北部，西脊的高度相当雄伟，成为M2内潮的第二代地点。如果到来的波是内潮，以前的模型表明，波的衰减取决于西脊坡度的超临界程度。如果入射波是内孔或内孤立波，我们的研究表明，内潮对超临界坡度失去了敏感性，脊高成为调节波衰减的主要因素。讨论了脊致衰减的机理。
The Luzon Strait is blocked by two meridional ridges at depths, with the east ridge somewhat higher than the west ridge in the middle reaches of the Strait. Previous numerical models identified the Luzon Strait as the primary generation site of internal M2tides entering the northern South China Sea (Niwa and Hibiya, 2004), but the role of the west-versus-east ridge was uncertain. We used a hydrostatic model for the northern South China Sea and a nonhydrostatic, process-oriented model to evaluate how the west ridge of Luzon Strait modifies westward propagation of internal tides, internal bores and internal solitary waves. The dynamic role of the west ridge depends strongly on the characteristics of internal waves and is spatially inhomogeneous. For M2tides, both models identify the west ridge in the middle reaches of Luzon Strait as a dampener of incoming internal waves from the east ridge. In the northern Luzon Strait, the west ridge is quite imposing in height and becomes a secondary generation site for M2internal tides. If the incoming wave is an internal tide, previous models suggested that wave attenuation depends crucially on how supercritical the west ridge slope is. If the incoming wave is an internal bore or internal solitary wave, our investigation suggests a loss of sensitivity to the supercritical slope for internal tides, leaving ridge height as the dominant factor regulating the wave attenuation. Mechanisms responsible for the ridge-induced attenuation are discussed.