A Simplified Algorithm to the Atmospheric Transmittance

It is very complex that the infrared radiation´s actual transmission process through earth´s atmosphere. There is interaction between radiation and atmospheric component. The radiation transmittance will be weakened because of the absorption and the scattering. The atmospheric transmittance is an important parameter to measure the attenuation. This paper summarizes the infrared radiation´s transmission process in atmosphere, studies the computation method of atmospheric transmittance, analyzes the absorption attenuation of the atmospheric gas such as steam and carbon dioxide, the scattering attenuation and the attenuation caused by meteorological condition, infers the computation method of the atmospheric equivalent path, and gives the atmospheric transmittance simplified algorithm. Finally this paper gives the atmospheric transmittance computation result under given meteorological condition, also gives the contrast curve with LOWTRAN7.0. The algorithm has certain reference value in the project application.