Inversion of stratospheric aerosol and gaseous constituents from spacecraft solar extinction data in the 0.38-1.0-microm wavelength region.

Inversion techniques for the retrieval of stratospheric aerosol, ozone, neutral density, and nitrogen dioxide vertical profiles from numerically simulated spacecraft solar extinction measurements have been analyzed. The analysis is applied toward the space flight mission of the Stratospheric Aerosol and Gas Experiment (SAGE), which will be flown on the Applications Explorer Mission B (AEM-B) spacecraft. The instrument has four radiometric channels located at selected intervals in the 0.38-1.0-,microm wavelength range. The expected retrieval accuracies are deterrrined from inverting simulated data with various experimental errors included. The results from this analysis assuming a horizontally homogeneous atmosphere indicate that aerosol, ozone, and neutral density vertical profiles can be retrieved to an accuracy better than 10% with about 1-km vertical resolution over most of the stratosphere. The results also show that nitrogen dioxide can be inverted to an accuracy of about 25% in the 25-38-km altitude ange. In addition, the effects of horizontally inhomogeneous distributions of aerosol and ozone on the retrieval accuracies are analyzed based on a simple inhomogeneous model of the atmosphere and found that there is only a small perturbation on the inversion accuracies.