Infrared Forcing by Greenhouse Gases
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From the CO2 Coalition,
W. A. van Wijngaarden¹ and W. Happer ²
¹Department of Physics and Astronomy, York University, Canada
²Department of Physics, Princeton University, USA
June 18, 2019
A shortened version of this important paper has been published on the arXiv preprint server hosted by Cornell University. The full version is provided here for the first time.
Download the full paper here: Infrared Forcing by Greenhouse Gases 2019 Revised 3 7 2022
Abstract
We review how the atmospheric temperatures and the concentrations of Earth’s five most important, naturally-occurring greenhouse gases, H₂O, CO₂, O₃, N₂O and CH₄ control the cloud-free, thermal radiative fluxes from the Earth to outer space. Computations based on the line intensities HITRAN data base alone, with no absorption continuums, are used to evaluate fluxes and intensities for greenhouse-gas concentrations similar to those of the year 2019. Calculated top-of-the atmosphere spectral intensities are in excellent quantitative agreement with satellite measurements at various latitudes. Also calculated are per-molecule forcings in a hypothetical, optically thin atmosphere, where there is negligible saturation of the absorption bands, or interference of one type of greenhouse gas with others. Then the per-molecule forcings are of order 10−²² W for H₂O, CO₂, O₃, N₂O and CH₄. For current atmospheric concentrations, the per-molecule forcings of the abundant greenhouse gases H₂O and CO₂ are suppressed by four orders of magnitude from optically-thin values because of saturation of the strong absorption bands and interference from other greenhouse gases. The forcings of the less abundant greenhouse gases, O₃, N₂O and CH₄, are also suppressed, but much less so. For current concentrations, the per-molecule forcings are two to three orders of magnitude greater for O₃, N₂O and CH₄, than those of H₂O or CO₂. Doubling the current concentrations of CO₂, N₂O or CH₄ only increases the forcings by a few per cent.
Introduction
https://wattsupwiththat.com/2022/03/07/infrared-forcing-by-greenhouse-gases/
