A31D-0086
Formation of Epoxide Derived SOA and Gas-Phase Acids through Aqueous Aerosol Processing in the Southeastern United States during SOAS
Wednesday, 16 December 2015
Poster Hall (Moscone South)
Kate Skog1, Alex Teng2, Tran B Nguyen3, Khoi Nguyen4, Sarah Ravenel Suda5, Lu Xu6, Gabriel A Isaacman-VanWertz7, Philip Allen Feiner8, Li Zhang9, Kevin Frederick Olson7, Abigail Koss10, Robert J Wild11, Jason St. Clair12, John Crounse13, Karsten Baumann14, Paul O Wennberg15, Markus Petters5, Ann Marie G Carlton16, Nga Lee Ng6, William H Brune8, Joost A De Gouw17, Allen H Goldstein7, Steven S Brown17, Eric S Edgerton18, V Faye McNeill19 and Frank N Keutsch20, (1)UW-Madison, Madison, WI, United States, (2)California Institute of Technology, Pasadena, CA, United States, (3)UC Irvine, Irvine, CA, United States, (4)Rutgers University New Brunswick, Department of Environmental Sciences, New Brunswick, NJ, United States, (5)North Carolina State University at Raleigh, Raleigh, NC, United States, (6)Georgia Institute of Technology Main Campus, Atlanta, GA, United States, (7)University of California Berkeley, Berkeley, CA, United States, (8)Pennsylvania State University Main Campus, University Park, PA, United States, (9)Pennsylvania State Univ, University Park, PA, United States, (10)University of Colorado at Boulder, Boulder, CO, United States, (11)Colorado University/NOAA/ESRL, Boulder, CO, United States, (12)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (13)California Institute of Technology, Division of Geological and Planetary Sciences, Pasadena, CA, United States, (14)Atmospheric Research and Analysis, Morrisville, NC, United States, (15)California Institute of Technology, Division of Engineering and Applied Science, Pasadena, CA, United States, (16)Peking University, Beijing, China, (17)NOAA Boulder, Boulder, CO, United States, (18)Atmospheric Research & Analysis, Inc., Cary, NC, United States, (19)Columbia University of New York, Palisades, NY, United States, (20)Harvard University, Cambridge, MA, United States
Abstract:
Secondary organic aerosol (SOA) contributes to climate and adversely affects human health, but the formation of SOA is poorly understood. Recent studies have proposed that aqueous processing of water-soluble compounds like glyoxal and IEPOX can help explain the abundance of organosulfates, higher oxygen to carbon ratios, and SOA abundance. A comprehensive set of ambient gas- and aerosol-phase data was collected during June and July of 2013 as part of the Southern Oxidant and Aerosol Study (SOAS) at the Centreville, AL ground site. Both gas-phase photochemistry and aqueous-phase aerosol chemistry were modeled using a zero-dimensional box model. While it has been suggested that glyoxal can contribute to aqueous aerosol through the formation of acids and higher-molecular-weight compounds, it did not produce enhanced aqSOA concentrations. Instead, processing of aqueous glyoxal resulted in the production of gas-phase acids. AqSOA consisted almost entirely of epoxide processing products, mainly from the processing of IEPOX to methyl tetrol, and the organosulfate. In addition, the pinene oxides contributed to the formation of aqSOA, through the formation of organosulfates, diols, and organonitrates. These data are consistent with the abundance of IEPOX and pinene oxide organonitrate derived SOA seen at this site.
