Abstract View
FIREX 2018/2019 Particle- and Gas-Phase Measurements: Emissions, Factor Analysis and Aging From Mobile Mass Spectrometers
FRANCESCA MAJLUF, Jordan Krechmer, Edward Fortner, Conner Daube, Christoph Dyroff, Joseph Roscioli, Tara Yacovitch, Benjamin Sumlin, Andrew Lambe, Scott Herndon, Manjula Canagaratna, Rajan K. Chakrabarty, John Jayne, Douglas Worsnop, Aerodyne Research, Inc.
Abstract Number: 541
Working Group: Aerosol Chemistry
Abstract
Better measurements and constraints of volatile organic compounds (VOCs) are critical to modeling the effects of increasingly frequent wildfires in the western USA on secondary organic aerosol formation and the oxidant budget. Using a Soot Particle Aerosol Mass Spectrometer (SP-AMS) and a Vocus Proton Transfer Reaction Mass Spectrometer (Vocus PTR) on board the Aerodyne Mobile Laboratory (AML) seven different fires over two years (FIREX 2018 and 2019) were sampled providing extensive chemical composition and aging information of both the gaseous (VOCs, oxidized VOCs) and particulate (black carbon, organic carbon) emissions from fires. Emission ratios calculated from SP-AMS and Vocus PTR measurements display statistically significant consistency with previous measurements of controlled fires in a laboratory setting. Within specific fires, chemically unique mass spectral signatures of smoldering and flaming are determined from factor analysis. Lastly, since our mobile platform sampled plumes across several distances, including directly adjacent from a fire, the effect of oxidative aging on gas phase species concentrations and on particle size and composition are characterized. Several photochemical aging markers and their reactivity with daytime and nighttime oxidants are investigated. These results are compared with in-situ aging experiments of fire plumes that are oxidized in an oxidation flow reactor.