AAAR 31st Annual Conference
October 8-12, 2012
Hyatt Regency Minneapolis
Minneapolis, Minnesota, USA
Abstract View
Regional Multi-generation Secondary Organic Aerosol Production from Major Anthropogenic and Biogenic Precursors
JINGYI LI, Qi Ying, Texas A&M University
Abstract Number: 491 Working Group: Carbonaceous Aerosols in the Atmosphere
Abstract Primary emitted volatile organic compounds (VOCs) produce semi-volatile organic compounds through a multi-generation oxidation process where intermediate reaction products further react with oxidants to generate a newer generation of VOC products with different volatility than the parent species. However, this multi-stage oxidation process is neglected by most regional aerosol models using a lumped gas phase chemical mechanism that only loosely coupled with the secondary organic aerosol modules. In this study, the most recent version of the Master Chemical Mechanism (MCM, version 3.2) is implemented in the CMAQ model to predict the multi-generation production of semi-volatile organic compounds. The amount of secondary organic aerosol (SOA) produced from these products is calculated using an online equilibrium partitioning SOA model. The CMAQ-MCM-SOA model is applied to a two-week air quality episode in southeast Texas in August and September 2006. Regional distributions of SOA as a function of generation and precursor are calculated and compared with results using a volatility basis set (VBS) approach to test the parameters used in the VBS.