Timeline

Jan 2017 - Present

Description

The increase in the frequency, extent, and duration of wildfires has become a great concern for air quality and climate because of the significant quantities of trace gases released from wildfires. Recent advances in analytical techniques have improved the identification and quantification of gas-phase wildfire emissions, yet the atmospheric chemistry of many VOCs remains poorly understood and inadequately represented in air quality models.

Certain classes of wildfire-derived VOCs, such as heterocyclic compounds, oxygenated aromatics, and monoterpenes, are known precursors to ozone (O3) and secondary organic aerosol (SOA), but their reaction pathways are not well characterized. To address this gap, this project used the Statewide Air Pollution Research Center (SAPRC) modeling system to develop and evaluate new gas-phase chemical mechanisms for key VOCs, including furans and phenols, and their major oxidation products.

Mechanisms were derived using a combination of published experimental data, molecular modeling, and estimates from SAPRC’s Mechanism Generation System (MechGen). These mechanisms were implemented in the SAPRC box model and evaluated against observations of VOC reactivity, nitric oxide (NO) decay, O3 formation, and radical levels. Notably, the mechanisms were developed without tuning to fit the evaluation data, but still demonstrated significantly improved model performance.

This work advances our understanding of wildfire VOC chemistry and helps close gaps in chemical mechanism representation. It also marks the first use of MechGen to connect gas-phase chemistry with SOA formation, enhancing its estimation methodology and increasing its visibility and accessibility within the atmospheric chemistry community.

Publication

  • Jiang, J., Shahid S.B., Zhang Y. Y., Cocker III, D.R. and Barsanti, K.C., 2025. Evaluation of A New Gas-Phase Mechanism of Phenolic Compounds under Atmospheric Relevant Conditions. (in preposition)
  • Carter, W.P., Jiang, J., Wang, Z. and Barsanti, K.C., 2025. The SAPRC Atmospheric Chemical Mechanism Generation System (MechGen). Geoscientific Model Development (under review). Link
  • Carter, W.P., Jiang, J., Orlando, J.J. and Barsanti, K.C., 2025. Derivation of atmospheric reaction mechanisms for volatile organic compounds by the SAPRC mechanism generation system (MechGen). Atmospheric Chemistry and Physics, 25(1), pp.199-242. Link
  • Li, Q., Jiang, J.(co-first), Afreh, I.K., Barsanti, K.C. and Cocker III, D.R., 2022. Secondary Organic Aerosol Formation from Camphene Oxidation: Measurements and Modeling. Atmospheric Chemistry and Physics, 22(5), pp.3131-3147. Link
  • Meehan-Atrash, J., Luo, W., McWhirter, K.J., Dennis, D.G., Sarlah, D., Jensen, R.P., Afreh, I., Jiang, J., Barsanti, K.C., Ortiz, A. and Strongin, R.M., 2021. The Influence of Terpenes on the Release of Volatile Organic Compounds and Active Ingredients to Cannabis Vaping Aerosols. RSC advances, 11(19), pp.11714-11723. Link
  • Jiang, J., Carter, W.P., Cocker III, D.R. and Barsanti, K.C., 2020. Development and evaluation of a detailed mechanism for gas-phase atmospheric reactions of furans. ACS Earth and Space Chemistry, 4(8), pp.1254-1268. Link

Presentation

  • Jiang, J., et al., Oct 2024, Modeling SOA Formation from Phenols Using an Updated Gas-Phase Mechanism and Revised SOA Parameters, American Association for Aerosol Research (AAAR) 42nd Annual Conference.
  • Brown-Steiner, B., Jiang, J., et al., Dec 2020, Incorporation of Detailed Gas-Phase Furan Mechanism into a Young Biomass Burning Plume Box Model. Atmospheric Chemical Mechanisms Conference 2020.
  • Jiang, J., et al., Aug 2019, Development of SAPRC Furan Mechanism (SAPRC-18F). Atmospheric Chemistry Gordon Research Conference 2019.
  • Jiang, J., et al., Sep 2018, Developing the SAPRC Gas-Phase Chemical Mechanism and Chamber-Based SOA Parameterizations for Evaluating Biomass-Burning Derived SOA from Furan and Furan Derivatives. International Aerosol Conference 2018.