Atmospheric concentration profile reconstructions from radiation measurements

We consider the reconstruction of vertical concentration profiles of atmospheric gases from a spectral distribution of radiation measured from a space-borne infrared spectrometer. Under some separability assumptions of the gases’ spectral absorption coefficients, we obtain uniqueness results on the reconstruction of concentration profiles from (multiple-wavenumber) radiance measurements and provide an explicit reconstruction procedure. We show that the reconstruction is a severely ill-posed problem. To address the reconstruction of localized layers, such as ozone or dust layers, we model the reconstruction of strong localized variations in the concentration profiles by using asymptotic expansions in the layer thickness. Assuming the background is known, we obtain that the location as well as the product of the concentration variability within the layer multiplied and the thickness of the layer may be reconstructed from moderately noisy data. The reconstructions of both the concentration and the thickness of the layer require more accurate data.