Chinese Optics Letters, 2007, 5 (3): 125, Published Online: Mar. 12, 2007
Effect of the reflection of underlying surface on sky radiance distribution Download: 550次
大气与海洋光学 天空亮度 下垫面 朗伯反射 混合修正delta-Eddington近似 迭代法 多次反射 010.1290 Atmospheric optics 240.0240 Optics at surfaces 010.1300 Atmospheric propagation
Abstract
Sky radiance might be influenced by the multiple reflectance between the earth's albedo surface and the atmosphere. Based on the Lambert's law and the radiative transfer equation (RTE), a model is developed to calculate the additional sky radiance at wavelengths of 0.4-3 microns due to the reflectance contribution of the underlying surface. The iterative method is used to calculate sky radiance without the reflectance from underlying surface. The hybrid modified delta-Eddington approximation is used to compute the atmospheric reflection of the radiation from the earth's surface. An interaction factor is introduced to deal with the multiple reflectance between the atmosphere and the underlying surface. The sky radiance increment is evaluated for some different albedos of the earth's surface. The results show that the sky radiance increment rises rapidly while viewing zenith angle is near to 90 deg., and the larger the albedo of the earth's surface is, the more obvious this effect appears.
Chunping Yang, Ling Wei, Jian Wu, Jie Leng. Effect of the reflection of underlying surface on sky radiance distribution[J]. Chinese Optics Letters, 2007, 5(3): 125.