An onion-peeling iterative, least-squares relaxation method to retrieve mixing ratio profiles from limb thermal emission spectra is presented. The method has been tested on synthetic data, containing various amounts of added random noise for O3, HNO3, and N2O. The retrieval method is used to obtain O3 and HNO3 mixing ratio profiles from high-resolution thermal emission spectra. Results of the retrievals compare favorably with those obtained by others.
William A. Shaffer, Virgil G. Kunde, and Barney J. Conrath, "Retrieval of constituent mixing ratios from limb thermal emission spectra," Appl. Opt. 27, 3482-3491 (1988)