09 Sep 2021
09 Sep 2021
Status: this preprint is currently under review for the journal ACP.

Emission factors of long-lived volatile organic compounds from the 2019–2020 Australian wildfires during the COALA campaign

Asher P. Mouat1, Clare Paton-Walsh3, Jack B. Simmons3, Jhonathan Ramirez-Gamboa3, David W. T. Griffith3, and Jennifer Kaiser1,2 Asher P. Mouat et al.
  • 1Department of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta GA 30332, USA
  • 2Department of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta GA 30332, USA
  • 3School of Earth, Atmospheric, and Life Sciences, University of Wollongong, Wollongong, NSW, Australia 2522

Abstract. In 2019/2020, Australia experienced its largest wildfire season on record. Smoke covered hundreds of square kilometers across the southeastern coast and reached the site of the 2020 COALA (Characterizing Organics and Aerosol Loading over Australia) field campaign in New South Wales. Using a subset of nighttime observations made by a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS), we calculate emission ratios (ERs) and factors (EFs) for 21 volatile organic compounds (VOCs). We restrict our analysis to VOCs with sufficiently high lifetimes to be minimally impacted by oxidation over the ~8 h between when the smoke was emitted and when it arrived at the field site. We use oxidized VOC to VOC ratios to assess the total amount of radical oxidation: maleic anhydride/furan to assess OH oxidation, and (cis-2-butenediol + furanone)/furan to assess NO3 oxidation. We compare ERs calculated from the freshest portion of the plume to ERs calculated using the entire nighttime period. Finding good agreement between the two, we are able to extend our analysis to VOCs measured in more chemically aged portions of the plume. Our analysis provides ERs and EFs for 9 compounds not previously reported for temperate forests in Australia: acrolein, pentanones/methylbutanal, methyl propanoate, methyl methacrylate, propene, maleic anhydride, benzaldehyde, methyl guaiacol, and methylbenzoic acid. We compare our results with two studies in similar Australian biomes, and two studies focused on US temperate forests. We find mixed agreement for EFs presented from previous studies of Australian wildfires, and generally good agreement with studies focused on fires in the Western US. This suggests that comprehensive field measurements of biomass burning VOC emissions in other regions may be applicable to Australian temperate forests.

Asher P. Mouat et al.

Status: final response (author comments only)

Comment types: AC – author | RC – referee | CC – community | EC – editor | CEC – chief editor | : Report abuse
  • RC1: 'Comment on acp-2021-742', Anonymous Referee #1, 04 Oct 2021
  • RC2: 'Comment on acp-2021-742', Anonymous Referee #2, 28 Oct 2021

Asher P. Mouat et al.

Asher P. Mouat et al.


Total article views: 627 (including HTML, PDF, and XML)
HTML PDF XML Total Supplement BibTeX EndNote
458 150 19 627 33 6 3
  • HTML: 458
  • PDF: 150
  • XML: 19
  • Total: 627
  • Supplement: 33
  • BibTeX: 6
  • EndNote: 3
Views and downloads (calculated since 09 Sep 2021)
Cumulative views and downloads (calculated since 09 Sep 2021)

Viewed (geographical distribution)

Total article views: 636 (including HTML, PDF, and XML) Thereof 636 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
Latest update: 28 May 2022
Short summary
We examine emissions of volatile organic compounds from 2019/2020 wildfires in forested regions of Australia. We find that biomass burning in temperate regions of the US and Australia emit similar species, when variability in sampling methods are taken into account. This suggests that studies of wildfires in one region may be used to help improve air quality models in other parts of the world.