Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 5 1 2005 10.5194/acpd-5-155-2005 http://www.atmos-chem-phys-discuss.net/5/155/2005/ http://www.atmos-chem-phys-discuss.net/5/155/2005/acpd-5-155-2005.html http://www.atmos-chem-phys-discuss.net/5/155/2005/acpd-5-155-2005.pdf 155 178 2005-01-12 Fall vortex ozone as a predictor of springtime total ozone at high northern latitudes S. R. Kawa P. A. Newman R. S. Stolarski R. M. Bevilacqua Atmospheric Chemistry and Dynamics Branch, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA Naval Research Laboratory, Washington, DC, USA Understanding the impact of atmospheric dynamical variability on observed changes in stratospheric O₃ is a key to understanding how O₃ will change with future climate dynamics and trace gas abundances. In this paper we examine the linkage between interannual variability in total column O₃ at northern high latitudes in March and lower-to-mid stratospheric vortex O₃ in the prior November. We find that these two quantities are significantly correlated in the years available from TOMS, SBUV, and POAM data (1978–2004). Additionally, we find that the apparent decadal shift in March O₃ variability from the 1980s to years post-1990 is also seen in the November vortex O₃, so that interannual variability in both quantities is largely driven by the later years. The cause of this correlation is not clear, however. Interannual variations in March total O₃ are known to correspond closely with variations in winter stratospheric wave driving consistent with the effects of varying residual circulation, temperature, and chemical loss. Variation in November vortex O₃ may also depend on dynamical wave activity, however, the dynamics in fall are less variable than in winter and spring. We do not find significant correlations of dynamic indicators for November such as temperature, heat flux, or polar average total O₃ with the November vortex O₃, nor with dynamical indicators later in winter and spring that might lead to a connection to March. We discuss several potential hypotheses for the observed correlation but do not find strong evidence for any considered mechanism. We present the observations as a phenomenon whose understanding may improve our ability to predict the dependence of O₃ on changing dynamics and chemistry.