Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 5 6 2005 10.5194/acpd-5-12103-2005 http://www.atmos-chem-phys-discuss.net/5/12103/2005/ http://www.atmos-chem-phys-discuss.net/5/12103/2005/acpd-5-12103-2005.html http://www.atmos-chem-phys-discuss.net/5/12103/2005/acpd-5-12103-2005.pdf 12103 12117 2005-11-24 Large decadal scale changes of polar ozone suggest solar influence B.-M. Sinnhuber P. von der Gathen M. Sinnhuber bms@iup.physik.uni-bremen.de M. Rex G. König-Langlo S. J. Oltmans Institute of Environmental Physics, University of Bremen, Bremen, Germany Alfred-Wegener-Institute for Polar and Marine Research, Research Unit Potsdam, Potsdam, Germany Alfred-Wegener-Institute for Polar and Marine Research, Bremerhaven, Germany NOAA Climate Monitoring and Diagnostics Laboratory, Boulder, Colorado, USA Long-term measurements of Arctic ozone show an unexpectedly large decadal scale variability in the mid-stratosphere during winter. Negative ozone anomalies are strongly correlated with the flux of energetic electrons in the radiation belt, which is modulated by the 11-year solar cycle. The magnitude of the observed decadal ozone changes (≈20%) is much larger than any previously reported solar cycle effect in the atmosphere up to this altitude. The early-winter ozone anomalies subsequently propagate downward into the lower stratosphere and may even influence total ozone and meteorological conditions during spring. These findings suggest a previously unrecognized mechanism by which solar variability impacts on climate through changes in polar ozone.