HR: 16:20h
AN: A24A-01    [Abstracts]
TI: Overview of the Megacity Aerosol Experiment: Mexico City (MAX-Mex)
AU: * Gaffney, J S
EM: jsgaffney@ualr.edu
AF: University of Arkansas at Little Rock, 2801 S. University Avenue Chemistry Department, Little Rock, AR 72204-1099, United States
AB: Tropospheric aerosols can play an important role the radiative balance of the globe. This is due to their ability to scatter and absorb solar radiation. The sign of this forcing will depend on their chemical composition and size, their lifetimes, and position in the atmosphere. Major sources of aerosols are now coming from megacities: Cities with more than 10 million population. As part of the MILAGRO campaign, the Megacity Aerosol Experiment: Mexico City was conducted by the Atmospheric Science Program of the Climate Change Research Division of the Department of Energy in collaboration with the scientists supported by NSF, NASA, and Mexican agencies. The preliminary results of the study will be overviewed and highlights of the efforts from both ground based and airborne measurements presented. Data from the study confirm that the megacity plumes are significant sources of both primary and secondary aerosols into the regional scale, and black carbon and secondary aerosols are contributing to single scattering albedos in the Valley of Mexico and downwind that are substantially reduced when compared to other areas (such as the eastern United States). The potential of biomass burning as well as megacity plumes contributing to a decrease in the aerosol single scattering albedos (aerosol direct effects) on regional scales will be discussed. This work was performed as part of the Department of Energy's Megacity Aerosol Experiment - Mexico City under the support of the Atmospheric Science Program. "This researchwas supported by the Office of Science (BER), U. S. Department of Energy, Grant No. DE-FG02-07ER64328.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0360 Radiation: transmission and scattering
DE: 0365 Troposphere: composition and chemistry
DE: 0368 Troposphere: constituent transport and chemistry
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly