HR: 0800h
AN: A11A-0029    [Abstracts]
TI: Photochemical and Meteorological Conditions during the MCMA-2003 Field Measurement Campaign
AU: Molina, L T
EM: ltmolina@mit.edu
AF: Departments of Earth, Atmospheric and Planetary Sciences and of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 United States
AU: * de Foy, B
AF: Departments of Earth, Atmospheric and Planetary Sciences and of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 United States
AU: Molina, M J
AF: Departments of Earth, Atmospheric and Planetary Sciences and of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139 United States
AU: Caetano, E
AF: Centro de Ciencias de la Atm¢sfera, Universidad Nacional Aut¢noma de M‚xico, Circuito Exterior s/n, Ciudad Universitaria, Delegaci¢n Coyoac n, Mexico City, 04510 Mexico
AU: Magana, V
AF: Centro de Ciencias de la Atm¢sfera, Universidad Nacional Aut¢noma de M‚xico, Circuito Exterior s/n, Ciudad Universitaria, Delegaci¢n Coyoac n, Mexico City, 04510 Mexico
AU: Zitacuaro, A
AF: Centro de Ciencias de la Atm¢sfera, Universidad Nacional Aut¢noma de M‚xico, Circuito Exterior s/n, Ciudad Universitaria, Delegaci¢n Coyoac n, Mexico City, 04510 Mexico
AU: Ramos, R
AF: Secretary of Environment, Government of the Federal District, Agricultura 21, Colonia Escand¢n, Mexico City, 11800 Mexico
AU: Retama, A
AF: Secretary of Environment, Government of the Federal District, Agricultura 21, Colonia Escand¢n, Mexico City, 11800 Mexico
AU: Cardenas, B
AF: General Direction of the National Center for Environmental Research and Training (CENICA). National Institute of Ecology (INE), Perif‚rico 5000, Col. Insurgentes Cuicuilco, Del. Coyoac n, Mexico City, 04530 Mexico
AU: Martinez, A
AF: General Direction of the National Center for Environmental Research and Training (CENICA). National Institute of Ecology (INE), Perif‚rico 5000, Col. Insurgentes Cuicuilco, Del. Coyoac n, Mexico City, 04530 Mexico
AU: Reyes, R
AF: Secretary of Environment of the State of M‚xico, Palacio Municipal de Tlalnepantla de Baz, Tlalnepantla de Baz, PB Mexico
AU: Sosa, G
AF: Instituto Mexicano del Petr¢leo, Eje Central L zaro C rdenas 152, Col. San Bartola Atepehuacan, Mexico City, 07730 Mexico
AB: MCMA-2003 was a major field campaign of the atmospheric chemistry taking place in the Mexico City Metropolitan Area (MCMA) in April of 2003. April is in the transition from the dry to the wet season with predominant westerly synoptic winds and intense radiation heating leading to strong thermal mountain flows. Three basic types of meteorological conditions were identified: "Cold Surge", "O3-North" and "O3-South", corresponding to cloudy days associated with "Norte" events, peak ozone in the north of the city, and peak ozone in the south. The circulation associated with these is described both at the regional and local level, as high concentrations of both ozone and primary pollutants for each category make them equally relevant to chemical analyses of the basin. Modified wind roses (time roses) based on time of day categories instead of wind speed categories are used to identify shifts in wind directions associated with slope flows inside the basin and sea breeze flows outside of it. The photochemical episodes are compared with historical data from the RAMA monitoring network to assess the representativeness of MCMA-2003. The analysis of the episodes during the campaign shows the existence of one-day episodes where no build-up of pollutants is needed in order to attain very highly localized concentrations but where multi-day events lead to peaks covering a much larger geographic area.
DE: 3329 Mesoscale meteorology
DE: 0322 Constituent sources and sinks
DE: 0345 Pollution--urban and regional (0305)
DE: 0368 Troposphere--constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting