Computation and Comparison of Cloud Infrared Radiation Characteristics

摘要

Cloud is a common weather phenomenon in the sky. It is formed by condensation of water vapor in the atmosphere. It is a suspension composed of water droplets, ice crystals or their mixtures. The infrared radiation characteristics of clouds are related to the particles phase state in clouds, the particle radius distribution and the cloud optical thickness. They are also affected by the sun, earth surface types and atmospheric conditions. In this paper, it introduces the physical parameters of the ice crystals in cloud, and researches the scattering characteristics of ice crystals. Based on radiation transfer algorithms, an ice cloud radiation model is established. The ice cloud infrared radiation is analyzed that the ice clouds infrared radiation varies with optical thickness. It shows that when the cloud optical thickness is not large, the radiance of ice clouds decreases with the increase of optical thickness.