HR: 10:50h
AN: A42A-03    [Abstracts]
TI: Megacity Radiative Forcing: A Mexico City Case Study
AU: * Dubey, M
EM: dubey@lanl.gov
AF: Los Alamos National Laboratory, MSD462 LANL, Los Alamos, NM 87544, United States
AU: Olsen, S
EM: solsen@lanl.gov
AF: Los Alamos National Laboratory, MSD462 LANL, Los Alamos, NM 87544, United States
AU: Mazzoleni, C
EM: claudio@lanl.gov
AF: Los Alamos National Laboratory, MSD462 LANL, Los Alamos, NM 87544, United States
AU: Chylek, P
EM: chylek@lanl.gov
AF: Los Alamos National Laboratory, MSD462 LANL, Los Alamos, NM 87544, United States
AU: Zhang, Y
EM: yongxin@lanl.gov
AF: Los Alamos National Laboratory, MSD462 LANL, Los Alamos, NM 87544, United States
AU: Randerson, J T
EM: jranders@uci.edu
AF: University of California, Irvine, 3212 Croul Hall, Irvine, CA 92697-3100, United States
AU: Horowitz, L
EM: Larry.horowitz.noaa.gov
AF: GFDL/NOAA, PO Box 308 Princeton University, Princeton, NJ 08542-0308, United States
AB: We assess the radiative forcing of the largest megacity in North America, Mexico City. While particular aspects of the regional environmental impacts of cities on their surroundings have been thoroughly investigated, e.g., air quality and acid rain, relatively little effort has been focused on the net radiative impact of a megacity on global climate. The range of radiative impacts from a megacity covers many spatial and temporal scales from short-term regional-scale effects due to aerosols and relatively short-lived gases (ozone) to long-term global-scale impacts due to longer-lived trace gases (e.g., carbon dioxide, methane). In this study we combine chemistry-transport model simulations from the Model for Ozone And Related Chemical Tracers (MOZART-2) with in situ and satellite observations from the Aerosol Robotic Network (AERONET) and the Moderate Resolution Imaging Spectroradiometer (MODIS) to calculate the global radiative forcing of megacity emissions. We also explore the radiative impact of various emission control strategies that focus on improving regional air quality. Our results suggest that the warming by greenhouse gases like carbon dioxide and ozone can be moderated or exacerbated by aerosols depending on their optical properties. As the size and number of megacities increase and clean air regulations are implemented, metrics such as the net radiative forcing may become increasingly important in comparing the impact of urban centers and assessing the trade-offs between improving local air quality and minimizing global radiative impacts.
UR: http:aerosols.lanl.gov
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0345 Pollution: urban and regional (0305, 0478, 4251)
DE: 0365 Troposphere: composition and chemistry
DE: 1225 Global change from geodesy (1222, 1622, 1630, 1641, 1645, 4556)
DE: 1610 Atmosphere (0315, 0325)
SC: Atmospheric Sciences [A]
MN: 2007 Joint Assembly