Inverse Gaussian k-distributions

k-distributions corresponding to Malkmus' narrow band model are inverse Gau ssian distributions. Inverse Gaussian theory developments are therefore dir ectly relevant to gas radiative transfer modeling. The present text illustr ates some significant benefits that could be made from this observation: (i ) k-distribution formulations are simplified, (ii) numerical integration pr ocedures can be optimized for each new configuration type, and(iii) frequen tly encountered integrals can be solved analytically and numerical integrat ions can be avoided. This last point is illustrated with the computation of infra-red cooling rates in planetary atmospheres. (C) 1999 Elsevier Scienc e Ltd. All rights reserved.