The ability to detect oil spills remotely is important in marine environmental monitoring. The optical polarization remote sensing has the unique advantage of inversion of refractive index of spilled oils which is the key parameter for calculation of sunglint reflectance. Compared to nonpolarization optical image, the degree of linear polarization (DOLP) of spilled oil’s sunglint depends on the refractive index and viewing angles but not on the surface roughness. Accurate correction of sunglint reflectance can promote optical estimation of spilled oils. In this article, a polarized optical model was used to calculate equivalent refractive index of Deepwater Horizon (DWH) spilled oils using space-borne Polarization and Anisotropy of Reflectances for Atmospheric Sciences coupled with Observations from a Lidar (PARASOL) images covering Gulf of Mexico (GOM) in 2010. When the angle ( $\theta _{m}$ ) between the direction of the flat surface specular reflection and that of observation is less than 20°, the PARASOL-derived and modeled DOLPs agree well, and the atmospheric polarization effects can be neglected. The equivalent refractive index of the spilled oil area, which implies the relative proportions of seawater and spilled oil in each pixel, could be estimated using polarized remote sensing under sunglint. Furthermore, if the relationship between the equivalent refractive index and remote sensing reflectance ( $R_{rs}$ ) of spilled oils in the remote sensing images can be given, it might be used to correct the sunglint effect on various spilled oils, thereby leading to an improvement for optical quantifying spilled oil volume.

中文翻译：

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太阳光下PARASOL图像海洋溢油折射率的偏振远程反演

远程检测溢油的能力在海洋环境监测中很重要。光学偏振遥感具有独特的优势，可以反演溢油的折射率，这是计算阳光反射率的关键参数。与非偏振光学图像相比，溢油阳光的线性偏振度（DOLP）取决于折射率和视角，而不取决于表面粗糙度。太阳光反射率的准确校正可以促进溢油的光学估计。在本文中，偏振光学模型用于计算深水地平线 (DWH) 溢油的等效折射率，使用大气科学的星载偏振和反射各向异性，并结合 2010 年覆盖墨西哥湾 (GOM) 的激光雷达 (PARASOL) 图像观测. 当平面镜面反射方向与观测方向的夹角 ( $\theta _{m}$ ) 小于 20° 时，PARASOL 推导和建模的 DOLP 吻合良好，大气极化效应可被忽视了。溢油区的等效折射率，即每个像素中海水和溢油的相对比例，可以在阳光下使用偏振遥感进行估计。此外，