Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 3 2007 10.5194/acpd-7-9203-2007 http://www.atmos-chem-phys-discuss.net/7/9203/2007/ http://www.atmos-chem-phys-discuss.net/7/9203/2007/acpd-7-9203-2007.html http://www.atmos-chem-phys-discuss.net/7/9203/2007/acpd-7-9203-2007.pdf 9203 9233 2007-06-28 Thermodynamic characterization of Mexico City aerosol during MILAGRO 2006 C. Fountoukis A. Nenes nenes@eas.gatech.edu A. Sullivan R. Weber T. VanReken M. Fischer E. Matías M. Moya D. Farmer R. C. Cohen School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, USA School of Earth & Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, USA National Center for Atmospheric Research, Boulder, CO, USA Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico Department of Chemistry, University of California Berkeley, Berkeley, CA, USA now at: Department of Atmospheric Science, Colorado State University, Fort Collins, CO, USA now at: Laboratory for Atmospheric Research, Department of Civil & Environmental Engineering, Washington State University, Pullman, Washington, USA Fast measurements of aerosol and gas-phase constituents coupled with the ISORROPIA-II thermodynamic equilibrium model are used to study the partitioning of semivolatile inorganic species and phase state of Mexico City aerosol sampled at the T1 site during the MILAGRO 2006 campaign. 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