Location of surface albedo file for wavelength dependent surface albedo.
albedo_file file
The file must have two columns.
Column 1 is the wavelength in nm, and column 2 the corresponding
Lambertian surface albedo. An arbitrary wavelength grid may be chosen as the
albedo will be interpolated linearely to the wavelength grid used for the
radiation calculation. Comments start with #. Empty lines are ignored.
A large collection of spectral albedos are available e.g. at http://speclib.jpl.nasa.gov/
Baldridge2009.