A new technique for developing k-distributions

Abstract

This work is devoted to a new technique, which finds the shortest k-distribution series achievable in practice. Its novelty consists in the use of real atmospheric flux calculations to guide both the position of spectral bands and the k terms within each band. Wavenumber subintervals which have similar atmospheric absorption behavior are chosen, then a representative absorption coefficient is set to the value which best fit the results of line-by-line calculations of fluxes. This method of choosing one absorption coefficient to represent a large number of wavenumber subinterval contrasts with other published methods, and is responsible in large part for the improved computational efficiency. Moreover this technique works as well in the stratosphere as the troposphere and it permits a more accurate treatment of cloud scattering and absorption properties than other methods