Low-grazing angle backscattering data collected by a coherent dual-polarized radar installed on a fixed tower in the ocean are analyzed to investigate the properties of sea spikes attributable to wave breaking. The distribution of breaking wave speed is narrow-banded with an average speed between 2.0 and 2.6 m/s in mixed seas with wind speeds between 7 and 14.5 m/s. The corresponding breaking wavelength is between 2.5 and 4.3 m. The length or velocity scale of wave breaking is not proportional to the length or velocity scale of the dominant wave. This observation reflects the localized nature of the breaking process and may have significant implications on quantifying various breaking properties such as the energy dissipation or area of turnover by breaking waves. The fraction of sea spike coverage generally increases with wind speed but the trend of increase is modified by the intensity and relative direction of background swell. Parameterizations of sea spike coverage needs to take into consideration both wind and wave factors. Similarities and differences between sea spikes and whitecaps are discussed. In particular, while both quantities show a similar power law dependence on wind speed, the fraction of sea spike coverage is considerably higher than that of whitecap coverage. This result reflects the prevalence of steep features that produce quasi-specular facets and short-scale waves bounded to intermediate waves during breaking. These quasi-specular facets and bound waves contribute significantly to enhancing the radar sea return but may not entrain air to produce whitecap signature.
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机译：分析了安装在海洋固定塔上的相干双极化雷达收集的低掠角反向散射数据，以研究可归因于波浪破坏的海峰的特性。在混合海中风速在7至14.5 m / s之间的情况下，破碎波速度的分布是窄带的，平均速度在2.0至2.6 m / s之间。相应的破裂波长在2.5至4.3 m之间。破碎波的长度或速度尺度与主导波的长度或速度尺度不成比例。该观察结果反映了破碎过程的局部性质，并且可能对量化各种破碎特性（例如能量消耗或破碎波的周转面积）产生重大影响。通常，海峰覆盖率的分数随风速而增加，但增加的趋势因背景膨胀的强度和相对方向而改变。海峰覆盖范围的参数化需要同时考虑风和浪因素。讨论了海峰和白浪之间的异同。特别是，尽管两个量都显示出相似的幂律对风速的依赖关系，但海峰覆盖的比例却大大高于白帽覆盖的比例。该结果反映了陡峭特征的普遍性，这些特征在断裂过程中会产生准镜面和与中间波相关的短尺度波。这些准镜面和束缚波极大地增强了雷达海面回波，但可能不会夹带空气以产生白帽信号。
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