冰水混合云对可见光的吸收和散射特性

Absorption and scattering of light by ice-water mixed clouds

根据Mie理论,分别计算了由纯水、纯冰和冰-水同心球形粒子构成的云层在可见光波段的单次散射特性.根据辐射传输理论,利用叠加法数值计算了这三种不同构成的云层的反射函数,以及它们的平面反照率、透过率和吸收率.结果表明,冰云和冰_水云的反射函数和平面反照率在大部分散射角下要略小于水云,而透过率却比水云的大.通过具体的数值计算结果和理论分析,研究了水云的异常吸收现象.

Based on the Mie theory, the light scattering properties in the visible regions of clouds consisting of pure water, pure ice spheres and concentric water-ice spheres are computed respectively. The reflection function and plane albedo, transmissivity, absorptivity of the three types of clouds are evaluated with the addlng-doubling method by solving the radiative transfer equation. The numerical results show that the reflection function and plane albedo of ice clouds and ice-water clouds are slightly less than those of water clouds at most scattering angles, when the transmissivity is larger. A detailed theoretical analysis of the numerical results is presented, which explains the phenomenon of cloud absorption anomaly.