Visualizing solar radiance per molecule, per isotopologue

[M-Howorucha]

Hi,

I have been working with LBLRTM for only a few weeks now and am hoping someone in the community with more knowledge and experience than I could help with some best practices or recommendations related to the description in the title of this post.

The context is that I am trying to produce a series of plots (lets say just one for now) that show normalized radiance of solar radiation at the surface viewed at some angle, with user defined atmospheric profiles. The desired output plot should separate the absorption due to each molecule, and in some cases, by isotopologue, with a small vertical offset to easily distinguish them. A great many examples for what I have in mind can be found in the "Spectroscopic Atlas of Atmospheric Microwindows in the Middle Infra-Red" by Arndt Meier, Geoffrey C. Toon, Curtis P. Rinsland, Aaron Goldman and Frank Hase. IRF Technical Report 048, April 2004. PDF (19 MB)

I am able to produce the attached image by running LBLRTM, n times, (once per molecule to be simulated) with the concentration of every gas except the nth one forced to 0.0 ppmv for every layer. I can generate a (visually) similar output by creating a new TAPE3 file from LNFL for each molecule which only includes line parameters for that molecule. Neither of these methods seems "elegant" or even correct when considering continuum interactions in the real atmosphere.

The questions is, are either of these methods reasonable ways to interact with LBLRTM for this goal, or is there a "better" maybe even recommended way to accomplish this? Also, for the next step of separating isotopologues, is there a better way than continuing with the method of forcing profile concentrations to 0, and iterating through all the options?

The following issue seems to address some of my concerns, but leaves the question open and doesn't mention isotopologues.
#66

Thanks,
Michael H