ABSTRACT Doppler spectrum of backscattered sea echoes from slick-covered sea surfaces is investigated in this paper, with emphasis on exploring the influence of marine sea slicks damping effect on Doppler spectral signatures including Doppler shift and spectral bandwidth. Model of local balance of wave energy inputs and outputs in wavenumber space is utilized for describing marine slicks damping effect, and the ‘choppy wave’ model is adopted for describing non-linear hydrodynamic interactions between ocean waves. The second-order small-slope approximation model combined with Monte Carlo technique is utilized for evaluating Doppler spectrum of backscattered field from clean or contaminated sea surfaces. Numerical simulations show that Doppler spectral bandwidths in slicks are reduced for almost all of the incidence angles ranging from to , which is qualitatively consistent with wave-tank measurements. The Doppler shifts in slicks, however, can increase or decrease, depending strongly on incidence angle, which is also in qualitative agreement with measurements. The Doppler spectrum of radar sea echoes is promising in the detection marine slicks by virtue of radar Doppler signatures.

中文翻译：

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海洋浮油阻尼对粗糙海面反向散射回波多普勒谱的研究

摘要 本文研究了浮油覆盖海面的背向散射海回波的多普勒频谱，重点探讨了海洋浮油阻尼效应对多普勒频谱特征的影响，包括多普勒频移和频谱带宽。波数空间波能输入输出局部平衡模型用于描述海洋浮油阻尼效应，“波涛”模型用于描述海浪之间的非线性水动力相互作用。结合蒙特卡罗技术的二阶小斜率近似模型用于评估来自清洁或污染海面的背向散射场的多普勒频谱。数值模拟表明，对于从 到 的几乎所有入射角，浮标中的多普勒频谱带宽都减少了，这与波箱测量在质量上是一致的。然而，浮油中的多普勒频移可以增加或减少，这在很大程度上取决于入射角，这也与测量值定性一致。雷达海回波的多普勒频谱在利用雷达多普勒特征检测海洋浮油方面很有前景。