Far infrared atmospheric transmission spectra using the sun as a source have been obtained with a Fourier spectrometer from mountain top and from an aircraft in the low stratosphere. The spectra cover the range 15-60 cm-1 with a resolution of 0.065 cm-1. Some of the mountain-top spectra were made on an extra-ordinarily dry day when the quantity of precipitable water overhead was less than 250 ppt μm. Absorption features due to oxygen, water vapor, ozone, and nitrous oxide are present. The known rotational parameters of these molecules allow computation of the expected atmospheric transmission for a given distribution of absorbers. The methods of computation will be described and the comparison of observed and calculated transmittances discussed. The insensitivity of the absorption to the details of distribution of absorber limits the information which may be obtained from below about the distribution of absorber at higher altitudes.
W. G. Mankin, W. G. Mankin,
"Comparison Of Calculated And Observed Atmospheric Transmittances In The Far Infrared", Proc. SPIE 0067, Long-Wavelength Infrared, (10 November 1975); doi: 10.1117/12.954533; https://doi.org/10.1117/12.954533