In this paper we demonstrate the utility of the Polar Ozone and Aerosol Measurement (POAM)III data for providing semiglobal three-dimensional ozone fields during the Stratospheric Aerosoland Gas Experiment (SAGE) III Ozone Loss and Validation Experiment (SOLVE) winter. As asolar occultation instrument, POAM III measurements were limited to latitudes of 63°N to 68°Nduring the SOLVE campaign but covered a wide range of potential vorticity. Using establishedmapping techniques, we have used the relation between potential vorticity and ozone measured byPOAM III to calculate three-dimensional ozone mixing ratio fields throughout the NorthernHemisphere on a daily basis during the 1999/2000 winter. To validate the results, we haveextensively compared profiles obtained from ozonesondes and the Halogen Occultation Experimentto the proxy O3 interpolated horizontally and vertically to the correlative measurement locations. Onaverage, the proxy O3 agrees with the correlative observations to better than ~5%, at potentialtemperatures below about 900 K and latitudes above about 30°N, demonstrating the reliability ofthe reconstructed O3 fields in these regions. We discuss the application of the POAM proxy ozoneprofiles for calculating photolysis rates along the ER-2 and DC-8 flight tracks during the SOLVEcampaign, and we present a qualitative picture of the evolution of polar stratospheric ozonethroughout the winter.