Journal article
New formation and fate of Isoprene SOA markers revealed by field data-constrained modeling
NPJ climate and atmospheric science, Vol.6(1), 69
06/01/2023
DOI: 10.1038/s41612-023-00394-3
Abstract
Particulate 2-methyltetrols (2-MT) and 2-methylglyceric acid (2-MG) are typically used to indicate the abundance of isoprene-derived secondary organic aerosols (SOA). However, their formation and fate are not fully understood. In this study, we showed that particulate 2-MT and 2-MG collected at multiple monitoring sites under a wide range of atmospheric and emission conditions, with concentrations spanning six orders of magnitudes, are well reproduced with an expanded isoprene-SOA scheme implemented into the Community Multiscale Air Quality (CMAQ) model. The scheme considers their three-phase (gas-aqueous-organic phase) partitioning, formation from acid-driven multiphase reactions, and degradation by OH radicals in the gas and aqueous phases. The model results reveal that a non-aqueous formation pathway or direct biogenic emission is needed to supplement the commonly assumed acid-driven multiphase reaction process to explain the observed 2-MT concentrations. This missing pathway contributes to 20–40% of 2-MT in areas with aerosol pH<2 and more than 70% under less acidic conditions (pH~2–5), such as those encountered in the western US and China. The typical summertime gas-phase photochemical lifetimes of 2-MT and 2-MG are estimated to be 4–6 and 20–30 h, respectively, and their aqueous lifetimes are approximately 20–40 h. Our simulations show that predicted 2-MT is mainly influenced by its aqueous phase loss to OH, but 2-MG is more sensitive to gas phase OH loss due to the preferential partitioning of the two tracers in the aqueous and gas phases, respectively.
Details
- Title: Subtitle
- New formation and fate of Isoprene SOA markers revealed by field data-constrained modeling
- Creators
- Jie Zhang - Texas A&M UniversityJunyi LiuXiang DingXiao HeTianle ZhangMei ZhengMinsu ChoiGabriel Isaacman-VanWertzLindsay YeeHaofei ZhangPawel MisztalAllen H GoldsteinAlex B GuentherSri Hapsari BudisulistioriniJason D SurrattElizabeth A StoneManish ShrivastavaDui WuJian Zhen YuQi Ying
- Resource Type
- Journal article
- Publication Details
- NPJ climate and atmospheric science, Vol.6(1), 69
- DOI
- 10.1038/s41612-023-00394-3
- eISSN
- 2397-3722
- Publisher
- Nature Publishing Group
- Grant note
- name: Partly supported by M. Shrivastava’s DOE Biological and Environmental Research (BER) Early Career Project at the Pacific Northwest National Laboratory; DOI: 10.13039/501100001809, name: National Natural Science Foundation of China, award: 42030708, 42177090, 42030708, 42030708, 21177031
- Language
- English
- Date published
- 06/01/2023
- Academic Unit
- Chemistry; Chemical and Biochemical Engineering
- Record Identifier
- 9984436459902771
Metrics
7 Record Views