An Infrared Radiative Transfer Model. Part 1: Model Description and Comparison of Observations with Calculations

Abstract

A new model has been developed for calculating vertical profiles of longwave irradiance and heating rates. The infrared active bands taken into account include the pure rotational water vapor, the 6.3 µm water vapor, the 15 µm carbon dioxide, the 14 and 9.6 µm ozone, the 7.66 µm methane and the 7.78 µm nitrous oxide band systems. Nimbus 3 IRIS radiance spectra obtained on clear days near the BOMEX array were compared with theoretically calculated spectra to test the spectral and frequency integrated quality of the calculations for the 400 to 1400 cm?1 region. These comparisons combined with pessimistic estimates of errors in spectral regions not observed indicate that the clear-sky upward flux at the top of the atmosphere may be calculated to within 3%.