AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Variable Urban SOA Production Explained by Emissions and Photochemistry to Quantify its Impact on Mortality
BENJAMIN A. NAULT, Duseong Jo, Pedro Campuzano-Jost, Douglas Day, Weiwei Hu, Jason Schroder, James Allan, Manjula Canagaratna, Hugh Coe, Peter DeCarlo, Jessica Gilman, Patrick Hayes, Daven Henze, B. Thomas Jobson, Bill Kuster, Bernhard Rappenglueck, James Roberts, Jochen Stutz, Ezra Wood, Dominique Young, Bin Yuan, Brian McDonald, Joost de Gouw, Jose-Luis Jimenez, et al., CIRES, University of Colorado, Boulder
Abstract Number: 503 Working Group: Urban Aerosols
Abstract Secondary organic aerosol (SOA) is an important constituent of urban submicron aerosol around the world and one of the causes of poor air quality and premature mortality. However, urban SOA (USOA) sources and production remains poorly understood. We show that the production of USOA and gas-phase photochemical pollutants (Ox, HCHO, and PAN) across worldwide megacities (Beijing, Houston, London, Los Angeles, Mexico City, New York City and Boston, and Seoul) are strongly correlated to the emissions of specific types of volatile aromatic compounds (benzene, toluene, ethylbenzene, and xylenes). The differences in key USOA production metrics (normalized USOA concentration vs. time and USOA vs. Ox, HCHO, PAN) measured across these megacities are correlated with population density, and appear to be driven by differences in the relative importance of traffic and volatile chemical products as precursor sources. Using this observation, we provide one of the first nearly complete USOA mass closure for 7 different megacities on 3 continents by estimating IVOC emissions with 3 different methods. The observed relationships allow more accurate predictions of USOA, using the SIMPLE parameterization method, in the GEOS-Chem chemical transport model. We show that, globally, ~400,000 less premature deaths fewer year would occur if USOA precursors were regulated and removed.