THE LONDON, EDINBURGH, AND DUBLIN PHILOSOPHICAL MAGAZINE AND JOURNAL OF SCIENCE [FIFTH SERIES] APRIL 1896. vol 41, pp237-275 XXXI. On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground. By Prof. SVANTE ARRHENIUS
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High resolution calibrated atmospheric spectrum using the moon as light source. With permisson of J. Notholt, Institute of Environmental Physics, University of Bremen, Germany.

Seasonal influence on lunar transmission spectrum
A reconstruction of lunar transmission and sky emission spectra
for mid latitude summer and winter using Modtran

A reconstruction of the Langley Lunar spectrum
A reconstruction of the Langley Lunar observations (Moon-Sky residual) using Modtran

Comparison of Arrhenius (table II) and modern IR absorption

dispersion angle vs wavelength

Cauchy, Langley and quantum dispersion formula

interpolated values
Mapping of dispersion angle vs wavelength using modern NaCl IR properties
DATA SOURCE for NaCl optical properties:;;
A comparison of the 1886 extrapolation and Langley's 1900 correction of the infrared refraction index;

From the properties of the NaCl prism follows that Langley's spectral observations stop at 12.5 micron (i.e. corresponding dispersion angle 35 degrees).
This is well before the major CO2 absorption band at 15 micron.
CO2 and H2O transmission data

For a better comparison the CO2 and H2O modern spectra are mapped to the NaCl prism angle, so that Arrhenius'table II data directly can be compared.
Note that Arrhenius total transmission A fits well the water vapour spectrum and that Arrhenius CO2 and H2O values have no correspondence to modern values.
Modern CO2 and H2O transmission data compared with Arrhenius Table II

Online chapter I and II
Abridged version (all chapters)
full scan (warning 27.1 MB pdf!)

Make your own atmosphere spectrum recommended!

Scanned original tables I, II, III, VI and VII below

Table I
Table II
Table III
Table VI
Table VII
Langley revisited, a recalibration of his observations using modern data, see
Arrhenius was wrong, a recalculation using modern data, see

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page updated 15 February 2004