AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Known and Newly Identified Semi-Volatile Organic Compounds from Biomass Burning in Amazonia: Variability and Sources
REBECCA WERNIS, Lindsay Yee, Gabriel Isaacman-VanWertz, Nathan Kreisberg, Suzane de Sá, Yingjun Liu, Scot Martin, Lizabeth Alexander, Brett Palm, Weiwei Hu, Pedro Campuzano-Jost, Douglas Day, Jose-Luis Jimenez, Paulo Artaxo, Juarez Viegas, Antonio O. Manzi, Rodrigo A. F. Souza, Susanne Hering, Allen H. Goldstein, University of California, Berkeley
Abstract Number: 552 Working Group: Aerosol Chemistry
Abstract Aerosols are a source of great uncertainty in radiative forcing predictions and have poorly understood impacts on human health. In many environments, biomass burning contributes a significant source of primary aerosol as well as reactive gas-phase precursors that can form secondary organic aerosol (SOA). One class of these precursors, semi-volatile organic compounds (SVOCs), has been shown to have a large contribution to the amount of SOA formed from fire emissions. At present, SVOC emissions from biomass burning are poorly constrained and understanding their contributions to SOA formation is an important research challenge.
In the Amazonian dry season, biomass burning is a major source of gases and aerosols reducing regional air quality. As part of the GoAmazon 2014/5 field campaign, we deployed the Semi-Volatile Thermal desorption Aerosol Gas Chromatograph (SV-TAG) instrument at the rural T3 site, 60 km to the west of Manaus, Brazil to measure hourly concentrations of SVOCs in the gas and particle phases. This comprehensive technique detects thousands of compounds, enabling the discovery of previously unidentified compounds. In this work we explore compounds for which a correlation with well-known biomass burning tracers is observed to discover the identities of new markers. We discuss contributions to the total organic aerosol from well-known, rarely reported and newly-identified biomass burning markers. We present source apportionment analysis of the identified compounds to reveal chemically specific source factors. Additionally, we report gas-particle partitioning of all identified compounds with comparison to theoretical predictions. We find that the commonly used biomass burning tracer levoglucosan existed entirely in the particle phase and contributed 0.6% and 0.3% of total organic aerosol mass in the dry and wet seasons, respectively.