Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 9 1 2009 10.5194/acpd-9-3555-2009 http://www.atmos-chem-phys-discuss.net/9/3555/2009/ http://www.atmos-chem-phys-discuss.net/9/3555/2009/acpd-9-3555-2009.html http://www.atmos-chem-phys-discuss.net/9/3555/2009/acpd-9-3555-2009.pdf 3555 3762 2009-02-03 The formation, properties and impact of secondary organic aerosol: current and emerging issues M. Hallquist J. C. Wenger j.wenger@ucc.ie U. Baltensperger Y. Rudich D. Simpson M. Claeys J. Dommen N. M. Donahue C. George A. H. Goldstein J. F. Hamilton H. Herrmann T. Hoffmann Y. Iinuma M. Jang M. Jenkin J. L. Jimenez A. Kiendler-Scharr W. Maenhaut G. McFiggans Th. F. Mentel A. Monod A. S. H. Prévôt J. H. Seinfeld J. D. Surratt R. Szmigielski J. Wildt Department of Chemistry, Atmospheric Science, University of Gothenburg, 41296, Gothenburg, Sweden Department of Chemistry and Environmental Research Institute, University College Cork, Cork, Ireland Laboratory of Atmospheric Chemistry, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland Department of Environmental Sciences, Weizmann Institute, Rehovot 76100, Israel EMEP MSC-W, Norwegian Meteorological Institute, P.B. 32 Blindern, 0313 Oslo, Norway Department of Radio and Space Science, Chalmers University of Technology, 41296, Gothenburg, Sweden Department of Pharmaceutical Sciences, University of Antwerp (Campus Drie Eiken), Universiteitsplein 1, 2610 Antwerp, Belgium Center for Atmospheric Particle Studies, Carnegie Mellon Univ., Pittsburgh PA 15213, USA Université de Lyon, Lyon, 69626, France CNRS, UMR5256, IRCELYON, Institut de recherches sur la catalyse et l'environnement de Lyon, Villeurbanne, 69626, France Department of Environmental Science, Policy and Management, University of California, Berkeley, CA, USA Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK Leibniz-Institut für Troposphärenforschung, Permoserstrasse 15, 04318 Leipzig, Germany Johannes Gutenberg-Universität, Institut für Anorganische und Analytische Chemie, Duesbergweg 10–14, 55128 Mainz, Germany Department of Environmental Engineering Sciences, P.O. Box 116450, University of Florida, Gainesville, FL 32611-6450, USA Imperial College London, Centre for Environmental Policy, Silwood Park, Ascot, Berkshire, SL5 7PY, UK Department of Chemistry & Biochemistry; and CIRES, University of Colorado; UCB 216, Boulder, CO 80309-0216, USA Institut für Chemie und Dynamik der Geosphäre, ICG, Forschungszentrum Jülich, 52425 Jülich, Germany Department of Analytical Chemistry, Institute for Nuclear Sciences, Ghent University, Proeftuinstraat 86, 9000 Ghent, Belgium Centre for Atmospheric Sciences, School of Earth, Atmospheric & Environmental Sciences, University of Manchester, Simon Building, Manchester, M13 9PL, UK Laboratoire Chimie de Provence, UMR-CNRS 6264/Université de Aix-Marseille I, II and III, 3 place Victor Hugo – Case 29, 13331 Marseille Cedex 3, France Departments of Chemical Engineering and Environmental Science and Engineering, California Institute of Technology, Pasadena, CA 91125, USA Department of Chemistry, California Institute of Technology, Pasadena, CA 91125, USA Secondary organic aerosol (SOA) accounts for a significant fraction of ambient tropospheric aerosol and a detailed knowledge of the formation, properties and transformation of SOA is therefore required to evaluate its impact on atmospheric processes, climate and human health. The chemical and physical processes associated with SOA formation are complex and varied, and, despite considerable progress in recent years, a quantitative and predictive understanding of SOA formation does not exist and therefore represents a major research challenge in atmospheric science. This review begins with a description of the current state of knowledge on the global SOA budget and the atmospheric degradation mechanisms for SOA precursors. The topic of gas-particle partitioning theory is followed by an account of the analytical techniques used to determine the chemical composition of SOA. A survey of recent laboratory, field and modeling studies is also presented. 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