基于矢量辐射传输方程的基本理论,考虑不同性质云层和不同海雾浓度的影响,将现有简化的两层大气结构细化为三层进行处理,采用倍加累加方法仿真天空光经过多层大气环境的散射过程,基于Rayleigh散射和Mie散射算法分别对每层粒子分布特性进行描述,建立适用于不同典型海洋环境下天空光的偏振分布模式。在太阳子午线位置处,研究海面观测高度角与下行辐射偏振特性的变化关系,研究结果表明,天空光偏振度随观测高度角呈规律性变化,随着云层和海雾粒子的增大及光学厚度的增加,偏振度逐渐增大。本研究为复杂海洋环境下垂直探测时天气环境及观测位置的选择提供了理论参考。

Based on the basic theory of vector radiative transfer equation, considering the influence of different kinds of cloud layers and different concentrations of advection fog, we developed a simplified two-layer atmosphere structure to a three-layer one and applied an adding-doubling method to simulate the scattering process of skylights through multilayer atmosphere. Furthermore, with the Rayleigh and Mie theory, the distribution characteristics for atmosphere, cloud, and fog layers were described, respectively, and the adding-doubling method was utilized to build the polarization distribution model of skylights under different typical marine environments. In addition, we investigated the relationship between the degree of polarization (DOP) and the observed altitude angle on the meridian of the sun. The results show that the skylight DOP varied regularly with the observed altitude angle. Moreover, with the rise in the optical thickness and with the increase of the cloud size and advection fog particles, DOP gradually increased. In conclusion, this study provides theoretical references for the selection of weather conditions and observation locations in the vertical polarization detection under complicated marine environments.