10th International Aerosol Conference
September 2 - September 7, 2018
America's Center Convention Complex
St. Louis, Missouri, USA

Abstract View


Modeling Secondary Organic Aerosol (SOA) Formation from Biomass Burning in the Euro-Mediterranean Region during the Summer 2007

MARWA MAJDI, Karine Sartelet, Florian Couvidat, Grazia Maria Lanzafame, Mounir Chrit, Solene Turquety, Youngseob Kim, Bertrand Bessagnet, Alexandre Albinet, CEREA, Ecole des Ponts ParisTech– EdF R&D, France

     Abstract Number: 551
     Working Group: Aerosol Chemistry

Abstract
Secondary organic aerosols (SOA) contribute significantly to the mass of organic aerosols observed in the atmosphere. SOA are formed mainly by the oxidation of volatile organic compounds (VOCs) and intermediate and semi-volatile organic compounds (I/S-VOCs). Biomass burning (including forest fire and open-field burning) releases large quantities of gases and particles into the atmosphere but SOA formation in/from fire plumes are still relatively unknown due to high uncertainties in emissions and to the complexity of the physico-chemical processes involved.
Most chemistry-transport models (CTMs) include only a limited number of VOCs which leads to a considerable underestimation of SOA concentrations. This work aims at improving the modeling of SOA formation from the main VOCs emitted by biomass burning using the CTM of the air-quality platform Polyphemus. Targeted VOCs have been selected according to their high emission factors and high SOA yields. Aromatic compounds namely benzene, phenol, cresol, catechol, furan, naphthalene, methyl naphthalene, syringol and guaiacol have been considered. Their oxidation mechanisms in gas-phase have been developed based on chamber experiment results available in the literature and implemented into the model. I/S-VOCs are usually not included in emission inventories although their contribution to SOA is probably significant. Different parameterizations have been also used to simulate the ageing of I/S-VOCs emitted by the biomass burning and implemented (single-step oxidation, multi-step oxidation and the presence of non-traditional volatile organic compounds (NTVOCs)).
The performance of the model has been finally evaluated over the European-Mediterranean region for the summer 2007 marked by severe forest fire events especially in the Balkan and Greece. Sensitivity studies on the influence of the VOCs and I/S-VOCs chemical mechanisms on SOA formation have been also performed.