标题： 冰数据中现场波的高频谱峰观测：冰三体相互作用中的非线性波证据？ 显示英文标题

标题： Observations of high-frequency spectral peaks from in-situ waves in ice data: evidence for nonlinear waves in ice triad interactions?

摘要： 波浪在边缘海冰区（MIZ）以及更深的浮冰区的传播是一个关键现象，它影响海冰的破裂和漂移。 当波浪在海冰中传播时，如果海冰是固体、未开裂且足够厚，色散关系中可能会出现显著的弯曲弹性效应。 这导致色散关系为三波相互作用（也称为波三重态）提供了可能。 在此，我们报告了在冰中波浪功率谱密度中观察到的高频谱峰。 我们在两个时间序列数据集中显示，这些高频峰的存在伴随着谱双相干性的高值。 这是一个标志，表明高频峰与主谱能量峰中的频率成分相位锁定，并且是非线性耦合发生的必要条件。 此外，我们展示了一个包含多个紧密放置传感器的时间序列数据集，从交叉谱分析中恢复的色散关系与在双相干性峰值出现的相同频率下可能存在波三重态相容。 除了这些时间序列数据集中的观测结果外，我们还展示了从其他独立的冰中波浪功率谱密度数据集中也观察到了类似的高频峰，这些数据是从自主浮标通过铱星传输的。 这些结果表明，在某些波浪和海冰条件下，冰中波浪频谱成分之间的非线性能量转移可能发生。 这可能使能量从弱阻尼的低频波重新分配到更强烈衰减的高频频谱成分，这有助于冰中的能量耗散。 显示英文摘要

摘要： The propagation of waves through the marginal ice zone (MIZ) and deeper into pack ice is a key phenomenon that influences the breakup and drift of sea ice. When waves in ice propagate through a solid, non-cracked, thick enough sea ice cover, significant flexural elastic effects can be present in the dispersion relation. This results in a dispersion relation that opens up for 3-wave interactions, also known as wave triads. Here, we report the observation of high-frequency spectral peaks in the power spectral density of waves in ice spectra. We show, in two timeseries datasets, that the presence of these high-frequency peaks is accompanied by high values for the spectral bicoherence. This is a signature that the high-frequency peak is phase-locked with frequency components in the main spectral energy peak, and a necessary condition for nonlinear coupling to take place. Moreover, we show for a timeseries dataset that includes several closely located sensors that the dispersion relation recovered from a cross-spectrum analysis is compatible with the possible existence of wave triads at the same frequencies for which the bicoherence peak is observed. In addition to these observations in timeseries datasets, we show that similar high-frequency peaks are observed from additional, independent datasets of waves in ice power spectrum densities transmitted over iridium from autonomous buoys. These results suggest that nonlinear energy transfers between wave in ice spectral components are likely to occur in some waves and sea ice conditions. This may enable redistribution of energy from weakly damped low-frequency waves to more strongly attenuated higher-frequency spectral components, which can contribute to energy dissipation in the ice.