Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 3 2007 10.5194/acpd-7-6959-2007 http://www.atmos-chem-phys-discuss.net/7/6959/2007/ http://www.atmos-chem-phys-discuss.net/7/6959/2007/acpd-7-6959-2007.html http://www.atmos-chem-phys-discuss.net/7/6959/2007/acpd-7-6959-2007.pdf 6959 6997 2007-05-23 SAGE II measurements of stratospheric aerosol properties at non-volcanic levels L. W. Thomason l.w.thomason@larc.nasa.gov S. P. Burton B.-P. Luo T. Peter NASA Langley Research Center, Hampton, VA, USA Science Systems and Applications, Inc., Hampton, VA, USA Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland Since 2000, stratospheric aerosol levels have been relatively stable and at the lowest levels observed in the historical record. 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