CaltechAUTHORS
Published December 13, 2022 | Version public
Journal Article Metadata-only

Emission factors and evolution of SO₂ measured from biomass burning in wildfires and agricultural fires

Creators

  • 1. ROR icon Cooperative Institute for Research in Environmental Sciences
  • 2. ROR icon National Oceanic and Atmospheric Administration
  • 3. ROR icon University of Colorado Boulder
  • 4. ROR icon Goddard Space Flight Center
  • 5. ROR icon Bay Area Environmental Research Institute
  • 6. ROR icon California Institute of Technology
  • 7. ROR icon University of New Hampshire
  • 8. ROR icon Langley Research Center
  • 9. ROR icon University of Vienna
  • 10. ROR icon National Institute of Aerospace
  • 11. ROR icon National Center for Atmospheric Research
  • 12. ROR icon Environmental Protection Agency
  • 13. ROR icon University of Maryland, Baltimore County
  • 14. ROR icon Aerodyne Research
  • 15. ROR icon Science Systems and Applications (United States)
  • 16. ROR icon Scientific Aviation (United States)

Abstract

Fires emit sufficient sulfur to affect local and regional air quality and climate. This study analyzes SO₂ emission factors and variability in smoke plumes from US wildfires and agricultural fires, as well as their relationship to sulfate and hydroxymethanesulfonate (HMS) formation. Observed SO₂ emission factors for various fuel types show good agreement with the latest reviews of biomass burning emission factors, producing an emission factor range of 0.47–1.2 g SO₂ kg⁻¹ C. These emission factors vary with geographic location in a way that suggests that deposition of coal burning emissions and application of sulfur-containing fertilizers likely play a role in the larger observed values, which are primarily associated with agricultural burning. A 0-D box model generally reproduces the observed trends of SO₂ and total sulfate (inorganic + organic) in aging wildfire plumes. In many cases, modeled HMS is consistent with the observed organosulfur concentrations. However, a comparison of observed organosulfur and modeled HMS suggests that multiple organosulfur compounds are likely responsible for the observations but that the chemistry of these compounds yields similar production and loss rates as that of HMS, resulting in good agreement with the modeled results. We provide suggestions for constraining the organosulfur compounds observed during these flights, and we show that the chemistry of HMS can allow organosulfur to act as an S(IV) reservoir under conditions of pH > 6 and liquid water content >10⁻⁷ g sm⁻³. This can facilitate long-range transport of sulfur emissions, resulting in increased SO₂ and eventually sulfate in transported smoke.

Additional Information

Pamela S. Rickly and Andrew W. Rollins acknowledge support from NASA's Upper Atmosphere Composition Observations program. Maximilian Dollner, Manuel Schöberl, and Bernadett Weinzierl have received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation framework program under grant agreement no. 640458 (A-LIFE) and from the University of Vienna. Hongyu Guo, Pedro Campuzano-Jost, and Jose L. Jimenez were supported by NASA 80NSSC18K0630 and 80NSSC21K1451 and NSF AGS-1822664. Glenn M. Wolfe, Thomas F. Hanisco, Reem A. Hannun, Jason M. St. Clair, and Jin Liao acknowledge support from the NASA Tropospheric Composition program and the NOAA AC4 program (NA17OAR4310004). Samuel R. Hall and Kirk Ullmann are funded under NASA grant 80NSSC18K0638. The National Center for Atmospheric Research is sponsored by the National Science Foundation. We would like to thank the NASA DC-8 crew and management team for support during FIREX-AQ integration and flights. Data from FIREX-AQ are available at https://www-air.larc.nasa.gov/cgi-bin/ArcView/firexaq (last access: 1 October 2021). This research has been supported by the National Aeronautics and Space Administration (grant no. 20-UACO20-0021).

Additional details

Additional titles

Alternative title
Emission factors and evolution of SO2 measured from biomass burning in wildfires and agricultural fires

Identifiers

Eprint ID
118898
Resolver ID
CaltechAUTHORS:20230123-451320900.31

Funding

European Research Council (ERC)
640458
NASA
80NSSC18K0630
NASA
80NSSC21K1451
NSF
AGS-1822664
National Oceanic and Atmospheric Administration (NOAA)
NA17OAR4310004
NASA
80NSSC18K0638
NASA
20-UACO20-0021

Dates

Created
2023-02-01
Created from EPrint's datestamp field
Updated
2023-02-01
Created from EPrint's last_modified field

Caltech Custom Metadata

Caltech groups
Division of Geological and Planetary Sciences (GPS)