Molecular atmospheric transmittance function in the range of 2–400 μm and earth radiation balance

Abstract

Mechanisms of the influence of the atmospheric transmission function, in the range 2–400 μm and especially in the windows 8–13 and 3–4 μm, on the thermal balance of the Earth's atmosphere are discussed. The negative and positive feedbacks between the absorption of the outgoing heat radiation in the atmosphere and the heating of the Earth's surface are considered. The database GEISA-92, which provides spectral line parameters of atmospheric constituents, has been used for simulations of infrared radiation transfer and the Earth's radiation balance. The temperature dependence of the molecular transmission function is calculated, and three steady states for Earth radiation balance are obtained. A type of the radiation balance, leading to “closing” of the atmospheric transmittance window 8–13 μm and development of the explosive greenhouse effect, is discussed.