水云多角度偏振辐射特性研究

MULTI-ANGULAR POLARIZED RADIATION CHARACTERISTICS OF WATER CLOUDS

由球形水滴组成并分布在大气底层的水云,对全球辐射平衡和气候变化有重要的影响,其影响程度取决于水云本身的微物理特性和光学特性.在对近红外通道0.865μm波长处水云光学特性研究的基础上,采用矢量辐射传输方程模拟分析了大气层顶归一化辐射强度和归一化偏振辐射强度对水云微物理特征、光学特征和地表反照率的敏感性.模拟结果表明,光谱的多角度偏振遥感信息能够更有效地体现出水云微物理特征和光学特征,可以利用多角度偏振遥感信息反演各种云参数.为利用多角度偏振遥感数据反演水云各种微物理量提供了理论基础.

Water clouds, which are distributed at the bottom of atmosphere and composed of spherical water droplets, play an important role in Earth＇ s radiation balance and global climate change. The effects of water clouds are based on their microphysical and optical properties. Based on the studies of water clouds optical properties in 0. 865μm, the sensitivity of normalized radiance and polarized radiance intensities to water clouds optical parameters, such as effective radius, optical th.ickness and surface albedo, was evaluated by using vector radiative transfer model. The simulated results indicate that the information of muhidirectional polarized radiance can show the microphysical and optical properties of water clouds effectively, which can be used to retrieve the properties of water clouds. This study provides the basis for using the remote sensing data of multi-angular polarization to retrieve the properties of water clouds was proposed.