Alaskan Arctic coastlines are protected seasonally from ocean waves by the presence of coastal and shorefast sea ice. This study presents field observations collected during the autumn 2019 freeze up near Icy Cape, a coastal headland in the Chukchi Sea of the Western Arctic. The evolution of the coupled air‐ice‐ocean‐wave system during a 4‐day wave event was monitored using drifting wave buoys, a cross‐shore mooring array, and ship‐based measurements. The incident wavefield with peak period of 2.5 s was attenuated by coastal pancake and frazil sea ice, reducing significant wave height by 40% over less than 5 km of cross‐shelf distance spanning water depths from 13 to 30 m. Spectral attenuation coefficients are evaluated with respect to wave and ice conditions and the proximity to the ice edge. Attenuation rates are found to be three times higher within 500 m of the ice edge, relative to values farther in the ice cover. Attenuation coefficients are in the range of 〈2.3, 2.7〉x10^‐3 m⁻¹, and follow a power‐law dependence on frequency.

中文翻译：

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楚科奇海沿岸的薄煎饼和巴西海冰中海面波的衰减

沿海和海岸海冰的存在，使阿拉斯加的北极海岸线在季节性受到海浪保护。这项研究提出了在2019年秋季冻结在西北极楚科奇海沿岸岬角冰冷海角附近冻结的野外观测资料。使用漂流浮标，跨岸系泊阵列和舰船测量数据，监测了为期4天的海浪事件期间海冰耦合海浪系统的演变。高峰期为2.5 s的入射波场被沿海薄煎饼和巴西海冰衰减，在跨越13米至30 m的水深不到5 km的跨架距离内，波峰高度降低了40％。相对于波浪和冰况以及与冰边缘的接近程度来评估光谱衰减系数。相对于冰盖中更远的值，发现在冰边缘500 m内的衰减率高出三倍。衰减系数在<2.3，2.7> x10的范围内^‐3 m ^-1，并遵循幂律对频率的依赖。