AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Chemical Composition and Optical Properties of Wildland and Agricultural Biomass Burning Particles Measured Downwind during the BBOP Study
TIMOTHY ONASCH, John Shilling, Joda Wormhoudt, Arthur J. Sedlacek, Edward Fortner, Mikhail Pekour, Duli Chand, Shan Zhou, Sonya Collier, Qi Zhang, Lawrence Kleinman, Douglas Worsnop, Robert J. Yokelson, Kouji Adachi, Peter Buseck, Andrew Freedman, Leah Williams, Aerodyne Research, Inc.
Abstract Number: 322 Working Group: Carbonaceous Aerosols in the Atmosphere
Abstract The Biomass Burning Observation Project (BBOP), a Department of Energy (DOE) sponsored study, measured emissions from wildland fires in the Pacific Northwest and agricultural burns in the Central Southeastern US from the DOE Gulfstream-1 airborne platform over a four month period in 2013. The chemical composition of the particulate emissions were characterized using an Aerodyne Soot Particle Aerosol Mass Spectrometer (SP-AMS) and Single Particle Soot Photometer (SP2) and will be presented in the context of the fire location, combustion conditions, and optical property measurements, including extinction and single scattering albedos. The SP-AMS was operated with both laser and resistively heated tungsten vaporizers, alternatively turning the laser vaporizer on and off. With the laser vaporizer off, the instrument operated as a standard high resolution AMS. Under these sampling conditions, the non-refractory chemical composition, including the level of oxidation (i.e., O:C, H:C, and organic mass/organic carbon ratios, OM:OC), of the biomass burning particles was characterized as a function of the fuel type burned, modified combustion efficiency, and degree of aging during downwind transport. With the laser vaporizer on, the SP-AMS was also sensitive to the refractory black carbon (rBC) content, in addition to the non-refractory components. Information on the mass of rBC, the OM/rBC ratio, and the Rbc (coat-to-core) ratio was examined, focusing on correlations with the simultaneous optical measurements.