Abstract
In the 4.2-μ to 5-μ region of the spectrum, the absorption in the earth’s atmosphere is primarily due to the 4.3-μ bands of CO2, the 4.6-μ bands of N2O, and the 4.7-μ bands of CO. These minor constituents appear to be uniformly distributed in the atmosphere. As a result, the absorption in a small frequency interval can be written as a function of atmospheric pressure and temperature. The spectral absorption is calculated for homogeneous absorber path lengths representative of various heights in the telluric atmosphere. Application of the Curtis–Godson approximation allows the calculations to be extended to real, nonhomogeneous atmospheric paths. The spectral energy distribution of the radiation passing through various isobaric levels of the earth’s atmosphere is presented for several model atmospheres. The quasi-statistical band model is used to compute the spectral absorption in the region 2000 cm−1 to 2400 cm−1 at intervals of 5 cm−1. A normal abundance of isotopic molecules is assumed and a total of ninety-nine vibrational transitions are considered. Spectral absorption computed for the individual molecules is shown to be in good agreement with laboratory data.
© 1965 Optical Society of America
Full Article | PDF ArticleMore Like This
L. D. Gray
Appl. Opt. 4(11) 1494-1499 (1965)
P. J. Berry, C. B. Farmer, and D. B. Lloyd
Appl. Opt. 4(9) 1045-1050 (1965)
D. Q. Wark and D. M. Mercer
Appl. Opt. 4(7) 839-845 (1965)