The infra-red spectra of atmospheric gases other than water vapour

The infra-red spectra of atmospheric gases t 9three molecules.This 'is illustrated in figure 1, which indicates the positions and approximate intensities of the main bands in the spectrum, the intensities being shown as the percentage absorption of the estimated continuous background emitted by the sun.This diagram should not be treated as an accurate representation.It has been rapidly prepared from a number of sources (Langley and Abbott, 1900; Adel, Slipher and Barker, 1935; Adel, 1938), but the qualitative picture it presents is very helpful in much of the discussion to follow.Recently a much more detailed plot of the atmospheric spectrum between 2 p and 14p has been made by Adel (1941 a 4 1 f), using a grating spectrometer.Unfortunately, curves published so far by Adel (1941 c, 41 e, 41 f,) apply only to the region between 7 ,U and 14 p,* and it is not practicable to reproduce these in this Report.The generally accepted interpretations of the atmospheric absorptions are marked on figure 1.It will be noticed that below 7 p all absorptions (with the Adel (1942) has recently published an extension of the atmospheric spectrum t o 2 4 p which proves that absorptjon is not comp!e?e beyond 14p as was formerly supposed, z * Note added in Proof. 3-2