A225-0015
Ozone Production from Wildfires during FIREX-AQ
Wednesday, 16 December 2020
Poster
Lu Xu1, Krystal Vasquez2, John D Crounse2, Hannah M Allen1, Paul O Wennberg2, Thomas B Ryerson3, Ilann Bourgeois4, Matthew Mitchell Coggon5, Georgios Gkatzelis6, Kanako Sekimoto7, Carsten Warneke6, Aaron Lamplugh6, Jessica Gilman8, Pamela Rickly9, Andrew W Rollins10, Caroline Womack10, Jakob Lindaas11, Steven S Brown8, Thomas F Hanisco12, Glenn M Wolfe13, Jason M St Clair14, Jin Liao15, Reem A Hannun16, Alan Fried17, Petter Weibring17, Dirk Richter17, James Walega17, Hongyu Guo18, Pedro Campuzano Jost18, Jose L Jimenez19, Young Ro of Lee20, David Tanner21, L Gregory Huey21, Glenn S Diskin22 and Thaopaul V Bui23, (1)California Institute of Technology, Pasadena, CA, United States, (2)California Institute of Technology, Division of Geological and Planetary Sciences, Pasadena, CA, United States, (3)NOAA ESRL Chemical Sciences Division, Boulder, CO, United States, (4)NOAA Chemical Sciences Division, Boulder, CO, United States, (5)California Institute of Technology, Department of Chemical Engineering, Pasadena, CA, United States, (6)CIRES and NOAA ESRL, Chemical Sciences Laboratory, Boulder, CO, United States, (7)NOAA Boulder, Boulder, CO, United States, (8)NOAA Earth System Research Laboratory, Chemical Sciences Laboratory, Boulder, CO, United States, (9)Indiana University Bloomington, School of Public and Environmental Affairs, Bloomington, IN, United States, (10)NOAA Earth System Research Laboratory, Chemical Sciences Division, Boulder, CO, United States, (11)Harvard University, Earth and Planetary Sciences, Cambridge, MA, United States, (12)NASA GSFC, Greenbelt, MD, United States, (13)NASA Goddard Space Flight Center, Greenbelt, MD, United States, (14)University of Maryland Baltimore County, Baltimore, MD, United States, (15)Universities Space Research Association and NASA Goddard Space Flight Center, Greenbelt, MD, United States, (16)Harvard Univ/Anderson Group, Cambridge, MA, United States, (17)University of Colorado at Boulder, Institute of Arctic and Alpine Research, Boulder, CO, United States, (18)University of Colorado Boulder, Boulder, CO, United States, (19)University of Colorado at Boulder, Cooperative Institute for Research in Environmental Sciences (CIRES) and Department of Chemistry, Boulder, CO, United States, (20)Georgia Institute of Technology, Atlanta, United States, (21)Georgia Institute of Technology, School of Earth and Atmospheric Sciences, Atlanta, GA, United States, (22)NASA Langley Research Ctr, Hampton, VA, United States, (23)NASA Ames Research Center, Moffett Field, CA, United States
Abstract:
The ozone formation in wildfire plumes is highly variable, but the driving factors behind the variability is unclear, partly because of incomplete characterization of wildfire emissions and complex chemistry of ozone formation. In this study, we utilize comprehensive measurements of wildfire emissions onboard NASA DC-8 during the Fire Influence on Regional to Global Environments Experiment - Air Quality (FIREX-AQ) to investigate the ozone chemistry in western wildfires. We will discuss the key chemical variables in determining ozone formation, including the production of hydroxyl radical (OH), the reactivity of volatile organic compounds (VOCs), and the chemistry of organic peroxy radical (RO2). We will also present the evolution of these chemical variables as wildfire smoke transports. Analysis suggests that nitrous acid is the major OH source in fresh smoke. Aromatics and furans are significant contributors to VOC reactivity in fresh smoke, but their contributions rapidly decrease as wildfire plume ages. In contrast, the contribution of small oxygenated VOCs to VOC reactivity increases. The RO2 fate shows rapid transition from RO2+NO dominant regime to a mixed regime with increasing fraction of RO2+HO2 reaction. Lastly, we estimate the ozone production rate based on measured concentrations of VOCs and NOx and the estimation shows reasonable agreement with measured production rate.
