The relationship between absorption coefficient and temperature and their effect on the atmospheric cooling rate

Abstract

Several approaches are considered to determine the temperature effect on the absorption coefficient within a correlated k-distribution method. Taking CO 2 15 μ m in the 610– 730 cm - 1 region for example, the absorption coefficients and atmospheric cooling rates calculated using these approaches are compared with line-by-line integration. It is emphasized in this paper by numerical calculation that the effect of pressure on absorption coefficient is related to temperature and vise versa; the larger the pressure, the larger the effect of temperature on absorption coefficient. Results show that the temperature effect must be considered in radiative calculations although its effect on the absorption coefficient is much smaller than that of pressure.