The energetics of large amplitude, high-frequency nonlinear internal waves (NLIWs) observed over the New Jersey continental shelf are summarized from ship and mooring data acquired in August 2006. NLIW energy was typically on the order of 10sup5/sup Jmsup?1/sup, and the wave dissipative loss was near 50 W msup?1/sup. However, wave energies (dissipations) were ~10 (~2) times greater than these values during a particular week-long period. In general, the leading waves in a packet grew in energy across the outer shelf, reached peak values near 40 km inshore of the shelf break, and then lost energy to turbulent mixing. Wave growth was attributed to the bore-like nature of the internal tide, as wave groups that exhibited larger long-term (lasting for a few hours) displacements of the pycnocline offshore typically had greater energy inshore. For ship-observed NLIWs, the average dissipative loss over the region of decay scaled with the peak energy in waves; extending this scaling to mooring data produces estimates of NLIW dissipative loss consistent with those made using the flux divergence of wave energy. The decay time scale of the NLIWs was approximately 12 h corresponding to a length scale of 35 km (iO/i(100) wavelengths). Imposed on these larger scale energetic trends, were short, rapid exchanges associated with wave interactions and shoaling on a localized topographic rise. Both of these events resulted in the onset of shear instabilities and large energy loss to turbulent mixing.
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机译：根据2006年8月在新泽西州大陆架上观测到的大振幅高频非线性内波（NLIWs）的能量，总结了其在船舶和系泊设备中的数据。NLIW能量通常约为10 5 Jm ？1 ，并且波耗散损耗接近50 W m ？1 。但是，在特定的一周时间内，波能量（耗散）比这些值大10倍（约2倍）。通常，一包中的前导波在整个外层架上的能量增加，在层架断裂的近岸40 km附近达到峰值，然后由于湍流混合而损失了能量。波浪的增长归因于内部潮汐的孔状性质，因为表现出较大的远距离（长期持续几个小时）位移的比克ococline的波浪群通常在岸上具有更大的能量。对于船上观测的NLIW，衰减区域的平均耗散损耗与波的峰值能量成比例。将该比例扩展到系泊数据可以得出NLIW耗散损耗的估计值，该估计值与使用波能通量发散所得出的值一致。 NLIWs的衰减时间尺度约为12小时，对应于35 km的长度尺度（（100）个波长）。强加于这些更大的能量趋势上的是与波浪相互作用和局部地形上升上的浅滩相关的短而快速的交换。这两个事件都导致剪切不稳定性的开始以及湍流混合的大量能量损失。
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