The effects of instrument noise on estimating the spectral attenuation rates of ocean waves in sea ice are explored using synthetic observations in which the true attenuation rates are known explicitly. The spectral shape of the energy added by noise, relative to the spectral shape of the true wave energy, is the critical aspect of the investigation. A negative bias in attenuation that grows in frequency is found across a range of realistic parameters. This negative bias decreases the observed attenuation rates at high frequencies, such that it can explain the rollover effect commonly reported in field studies of wave attenuation in sea ice. The published results from five field experiments are evaluated in terms of the noise bias, and a spurious rollover (or flattening) of attenuation is found in all cases. Remarkably, the wave heights are unaffected by the noise bias, because the noise bias occurs at frequencies that contain only a small fraction of the total energy.

中文翻译：

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实地测量中的噪声引起的海冰中波衰减率的虚假翻转

利用合成观测方法探索了仪器噪声对海冰中海浪频谱衰减率估计的影响，其中明确知道了真实的衰减率。相对于真实波能量的频谱形状，由噪声添加的能量的频谱形状是研究的关键方面。在一系列实际参数中发现了衰减随频率增加的负偏差。这种负偏差会降低在高频下观察到的衰减率，从而可以解释在海冰中波浪衰减的现场研究中通常报道的翻转效应。根据噪声偏差评估了来自五个现场实验的已发布结果，并且在所有情况下均发现了衰减的虚假翻转（或平坦化）。值得注意的是