Large-amplitude internal tides, solitary waves, and turbulence in the central Bay of Biscay
Large-amplitude internal tides, solitary waves, and turbulence in the central Bay of Biscay
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DOI：
10.1002/grl.50533
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发表时间：
2013-06
影响因子：
5.2
通讯作者：
Xu Xie;Y. Cuypers;P. Bouruet-Aubertot;B. Ferron;A. Pichon;A. Lourenço;N. Cortes
中科院分区：
文献类型：
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作者：
Xu Xie;Y. Cuypers;P. Bouruet-Aubertot;B. Ferron;A. Pichon;A. Lourenço;N. Cortes
微观结构和细尺度测量收集在比斯开湾中部的MOUTON实验期间进行了分析，调查的内波和相关的混合动力学。在温跃层中观测到了激发内孤立波的大振幅内潮。ITs由模式3和4主导，而ISW投射在被困在温跃层中的模式1上。其中，ITs产生一个持久的窄剪切带，这是强烈相关的温跃层中的增强耗散率。这种强耗散率在ISW的存在下得到进一步加强。耗散率在此期间没有ISWs在很大程度上同意MacKinnon-Gregg标度为主导的低频模式的内部波场，而他们表现出较差的协议与Gregg-Henyey参数化有效的内部波场接近Garrett-Munk模型。与MacKinnon-Gregg标度的协议是一致的，湍流混合在这里是由低频内部潮汐剪切驱动的事实。
Microstructure and fine-scale measurements collected in the central Bay of Biscay during the MOUTON experiment are analyzed to investigate the dynamics of internal waves and associated mixing. Large-amplitude internal tides (ITs) that excite internal solitary waves (ISWs) in the thermocline are observed. ITs are dominated by modes 3 and 4, while ISWs projected on mode 1 that is trapped in the thermocline. Therein, ITs generate a persistent narrow shear band, which is strongly correlated with the enhanced dissipation rate in the thermocline. This strong dissipation rate is further reinforced in the presence of ISWs. Dissipation rates during the period without ISWs largely agree with the MacKinnon-Gregg scaling proposed for internal wavefields dominated by a low-frequency mode, while they show poor agreement with the Gregg-Henyey parameterization valid for internal wavefields close to the Garrett-Munk model. The agreement with the MacKinnon-Gregg scaling is consistent with the fact that turbulent mixing here is driven by the low-frequency internal tidal shear.