The lifecycle of semidiurnal internal tides over the northern Mid-Atlantic Ridge
The lifecycle of semidiurnal internal tides over the northern Mid-Atlantic Ridge
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DOI：
10.1175/jpo-d-17-0121.1
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发表时间：
2018-01
影响因子：
3.5
通讯作者：
C. Vic;A. N. Naveira Garabato;J. Green;C. Spingys;A. Forryan;Zhong‐Kuo Zhao;J. Sharples
中科院分区：
文献类型：
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作者：
C. Vic;A. N. Naveira Garabato;J. Green;C. Spingys;A. Forryan;Zhong‐Kuo Zhao;J. Sharples
摘要利用高分辨率系泊和微结构剖面仪和卫星资料，结合正斜压潮汐能转换理论模型，研究了亚速尔群岛以南大西洋中脊（MAR）扇区半日内潮的生命周期。系泊分析表明，内潮水平能量通量以模态1为主，能量密度主要分布在模态1 ~ 10之间。大多数模态都与持续内部潮汐的解释相容，这表明它们是由在mara上产生的波浪之间的相互作用造成的。因此，内部潮汐能量集中在山脊上方，最终可用于局部的湍流混合，正如从微观结构测量中估计的湍流能量耗散率升高所证实的那样。发现MAR上的能量密度的春季小潮调制源于强1型内潮的远程产生和辐射。
AbstractThe life cycle of semidiurnal internal tides over the Mid-Atlantic Ridge (MAR) sector south of the Azores is investigated using in situ, a high-resolution mooring and microstructure profiler, and satellite data, in combination with a theoretical model of barotropic-to-baroclinic tidal energy conversion. The mooring analysis reveals that the internal tide horizontal energy flux is dominated by mode 1 and that energy density is more distributed among modes 1–10. Most modes are compatible with an interpretation in terms of standing internal tides, suggesting that they result from interactions between waves generated over the MAR. Internal tide energy is thus concentrated above the ridge and is eventually available for local diapycnal mixing, as endorsed by the elevated rates of turbulent energy dissipation e estimated from microstructure measurements. A spring–neap modulation of energy density on the MAR is found to originate from the remote generation and radiation of strong mode-1 internal tides fr...