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Atmos. Chem. Phys. Discuss., 13, 379-435, 2013
www.atmos-chem-phys-discuss.net/13/379/2013/ doi:10.5194/acpd-13-379-2013 © Author(s) 2013. This work is distributed under the Creative Commons Attribution 3.0 License. |
Long term changes in the upper stratospheric ozone at Syowa, Antarctica
1Japan Meteorological Agency, Aerological Observatory, Tsukuba, Ibaraki, 305-0052, Japan
2Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder Colorado, USA
3NOAA/OAR/ESRL Climate Monitoring Division, 325 Broadway, Boulder, Colorado, USA
4NOAA/NWS/NCEP/Climate Prediction Center, Silver Spring, USA
5NOAA/NWS/NCEP/Climate Prediction Center, Wyle ST&E, McLean, VA, USA
6NorthWest Research Associates, Socorro, NM, USA
7New Mexico Institute of Mining and Technology, Socorro, NM, USA
8Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
Abstract. Analyses of stratospheric ozone data determined from Dobson Umkehr measurements since 1977 at the Syowa (69.0° S, 39.6° E), Antarctica station show a significant decrease in ozone at altitudes higher than that of the 4 hPa pressure level during the 1980s and 1990s. Ozone values over Syowa have remained low since 2001. The time series of upper stratospheric ozone from the homogenized NOAA (/2) SBUV 8.6 overpass data (± 4°, 24 h) are in qualitative agreement with Syowa station data. Ozone recovery during the austral spring over Syowa station appears to be slower than predicted by the Equivalent Effective Stratospheric Chlorine (EESC) curve. The long-term changes in station's equivalent latitude are derived from MERRA analysis at ~2 hPa and ~50 hPa. These data are used to attribute some of the upper and middle stratospheric ozone changes to the changes in vortex position relative to station location. In addition, high correlation of the Southern Hemisphere Annular Mode (SAM) with polar upper stratospheric ozone during years of maximum solar activity points toward a strong relationship between the strength of the Brewer-Dobson circulation and the polar stratospheric ozone recovery. We have analyzed the results of ozone profiles over Syowa determined from measurements of the Umkehr effect by Dobson ozone spectrophotometers. The ozone depletion attributable to CFCs is clearly visible in the record, but the recovery is slower than predicted. Further research indicates that dynamical and other chemical changes in the atmosphere are delaying the recovery over this station.
Citation: Miyagawa, K., Petropavlovskikh, I., Evans, R. D., Long, C., Wild, J., Manney, G. L., and Daffer, W. H.: Long term changes in the upper stratospheric ozone at Syowa, Antarctica, Atmos. Chem. Phys. Discuss., 13, 379-435, doi:10.5194/acpd-13-379-2013, 2013.