Retrieval of Ozone, NO2 and Aerosol Vertical Profiles from Limb Scatter Measurements

The Stratospheric Aerosol and Gas Experiment (SAGE III) instrument is being used to investigate the potential of limb scatter methods for atmospheric gas/aerosol vertical profile retrieval. The information contained in the Earth limb scattered sunlight measured by SAGE III has been shown to be sufficient to retrieve Ozone density from 10 km (or cloud top) to 50-55 km using UV and visible wavelengths [Rault, JGR 2005], as well as NO2 density from 15 to 40 km and stratospheric aerosol extinction profiles. Initial results have shown that the retrieved profiles compare favorably with correlative measurements, such as Ozone sondes and other satellite instruments (namely, SAGE II, HALOE, SAGE III in occultation, POAM, OSIRIS). The present paper summarizes the results of an extensive validation study for SAGE III limb scatter Ozone products. The validation analysis considers two SAGE III data sets, namely (1) measurements made while overpassing a series of ground stations belonging to the SHADOZ network during Summer 2004 and Fall 2004, and (2) measurements made during the Summer 2004 INTEX campaign over North America, North Atlantic and Northern Europe.