Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 7 1 2007 10.5194/acpd-7-3113-2007 http://www.atmos-chem-phys-discuss.net/7/3113/2007/ http://www.atmos-chem-phys-discuss.net/7/3113/2007/acpd-7-3113-2007.html http://www.atmos-chem-phys-discuss.net/7/3113/2007/acpd-7-3113-2007.pdf 3113 3177 2007-02-27 Air quality in North America's most populous city – overview of MCMA-2003 Campaign L. T. Molina ltmolina@mit.edu C. E. Kolb B. de Foy B. K. Lamb W. H. Brune J. L. Jimenez M. J. Molina Department of Earth, Atmospheric and Planetary Science, Massachusetts~Institute of Technology, Cambridge, MA, USA Molina Center on Energy and Environment, La Jolla, CA, USA Aerodyne Research, Inc., Billerica, MA, USA Saint Louis University, St. Louis, MO, USA Laboratory for Atmospheric Research, Department of Civil and Environmental Engineering, Washington State University, Pullman, WA, USA Department of Meteorology, Pennsylvania State University, University Park, PA, USA Dept. of Chemistry and Biochemistry, University of Colorado at Boulder, Boulder, CO, USA Cooperative Institute for Research in the Environmental Sciences (CIRES), University of Colorado at Boulder, Boulder, CO, USA Department of Chemistry and Biochemistry, University of California at San Diego, San~Diego, CA, USA Exploratory field measurements in the Mexico City Metropolitan Area (MCMA) in February 2002 set the stage for a major air quality field measurement campaign in the spring of 2003 (MCMA-2003). Involving over 100 scientists from more than 30 institutions in Mexico, the United States and Europe, MCMA-2003 revealed important new insights into the meteorology, primary pollutant emissions, ambient secondary pollutant precursor concentrations, photochemical oxidant production and secondary aerosol particle formation in North America's most populated and polluted megacity. A description of meteorological and atmospheric chemistry and aerosol microphysics measurements performed during MCMA-2003 is presented. More than three dozen published or submitted MCMA-2003 research papers are reviewed and key discoveries pertinent to understanding and improving air quality in Mexico City and similar megacities in the developing world are summarized. Arriaga, J. L., Escalona, S., Cervantes, A. D., Orduñez, R., and Lopez, T.: Seguimiento de COV en aire urbano de la ZMCM 1992-1996, in Contaminación Atmosférica, Vol. 2, edited by: Colin L. G. and Varela J. R., UAM, Mexico, 1997. 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R., Marquez, C. , Blanco, S., Cardenas, B., Kolb, C. E., Molina, L. T., and Molina, M. J.: Technical note: Evaluation of Standard Ultraviolet Absorption Ozone Monitors in a Polluted Urban Environment, Atmos. Chem. Phys., 6, 3163–3180, 2006. Dunlea, E. J., Herndon, S. C., Nelson, D. D., Volkamer, R. M., San Martini, F., Sheehy, P. M., Zahniser, M. S., Shorter, J. H., Wormhoudt, J. C., Lamb, B. K., Allwine, E. J., Gaffney, J. S., Marley, N. A., Grutter, M., Marquez, C., Blanco, S., Cardenas, B., Retama, A., Ramos Villegas, C. R., Kolb, C. E., Molina, L. T., and Molina, M. J.: Evaluation of nitrogen dioxide chemiluminescence monitors in a polluted urban environment, Atmos. Chem. Phys. Discuss., 7, 569–604, 2007. Dunn, M. J., Jimenez, J. L., Baumgardner, D., Castro, T., McMurry, P. H., and Smith, J. N.: Measurements of Mexico City nanoparticle size distributions: Observations of new particle formation and growth, Geophys. Res. Lett., 31, L10102, doi:10.1029/2004GL019483, 2004. 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