Location of Rayleigh scattering optical depth file.
rayleigh_tau_file file
Usually, the Rayleigh scattering
cross section is calculated from the air pressure provided in atmosphere_file
(scaled with pressure). Use this parameter only if you really want to specify
the optical depth directly (e.g. for a model intercomparison). The
optical thickness profile may be either monochromatic or spectral.
The format is exactly the same as for molecular_tau_file.