AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Examining New Pathways of Secondary Organic Aerosol Formation in a 3D Model: Role of Absorbed Water, Multi-generational Aging, Intermediate-Volatility Organics and Aqueous Chemistry
SHANTANU JATHAR, Christopher Cappa, V. Faye McNeill, Michael Kleeman, University of California, Davis
Abstract Number: 379 Working Group: Carbonaceous Aerosols in the Atmosphere
Abstract Numerous field campaigns have demonstrated the abundance of secondary organic aerosol (SOA) in urban, rural and remote environments. However, contemporary chemical transport models that include (a) semi-volatile SOA formation from gas-phase oxidation of volatile anthropogenic and biogenic precursors and (b) low-volatility SOA formation via condensed-phase chemistry are unable to predict the observed formation and properties of SOA. In this work, we examine the influence of absorbed water on the gas-particle partitioning of SOA and enhanced SOA formation from multi-generational aging, intermediate-volatility organics and aqueous processing of isoprene epoxide and glyoxal in a 3D air quality model. Simulations are performed for two domains, California and the Eastern United States, over representative summer episodes. SOA predictions from these new pathways are compared to those from traditional SOA pathways and to available measurements of SOA concentrations and properties. The ability of these new pathways to close the gap between predictions and measurements will then be discussed.