Resolving ambient organic aerosol formation and aging pathways with simultaneous molecular composition and volatility observations.

Autor: Lee BH; Department of Atmospheric Sciences, University of Washington, Seattle, WA, U.S.A., D'Ambro EL; Department of Chemistry, University of Washington, Seattle, WA, U.S.A., Lopez-Hilfiker FD; Department of Atmospheric Sciences, University of Washington, Seattle, WA, U.S.A., Schobesberger S; Department of Atmospheric Sciences, University of Washington, Seattle, WA, U.S.A., Mohr C; Department of Atmospheric Sciences, University of Washington, Seattle, WA, U.S.A., Zawadowicz MA; Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, U.S.A., Liu J; Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, U.S.A., Shilling JE; Atmospheric Sciences and Global Change Division, Pacific Northwest National Laboratory, Richland, WA, U.S.A., Hu W; Cooperative Institute for Research in Environmental Sciences and Department of Chemistry, University of Colorado, Boulder, CO, U.S.A., Palm BB; Cooperative Institute for Research in Environmental Sciences and Department of Chemistry, University of Colorado, Boulder, CO, U.S.A., Jimenez JL; Cooperative Institute for Research in Environmental Sciences and Department of Chemistry, University of Colorado, Boulder, CO, U.S.A., Hao L; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland., Virtanen A; Department of Applied Physics, University of Eastern Finland, Kuopio, Finland., Zhang H; Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, U.S.A., Goldstein AH; Department of Environmental Science, Policy, and Management, University of California, Berkeley, CA, U.S.A., Pye HOT; Office of Research and Development, Environmental Protection Agency, Research Triangle, NC, U.S.A., Thornton JA; Department of Atmospheric Sciences, University of Washington, Seattle, WA, U.S.A.
Jazyk: angličtina
Zdroj: ACS earth & space chemistry [ACS Earth Space Chem] 2020 Mar 19; Vol. 4 (3), pp. 391-402.
DOI: 10.1021/acsearthspacechem.9b00302
Abstrakt: Organic aerosol (OA) constitutes a significant fraction of atmospheric fine particle mass. However, the precursors and chemical processes responsible for a majority of OA are rarely conclusively identified. We use online observations of hundreds of simultaneously measured molecular components obtained from 15 laboratory OA formation experiments with constraints on their effective saturation vapor concentrations to attribute the VOC precursors and subsequent chemical pathways giving rise to the vast majority of OA mass measured in two forested regions. We find that precursors and chemical pathways regulating OA composition and volatility are dynamic over hours to days, with their variations driven by coupled interactions between multiple oxidants. The extent of physical and photochemical aging, and its modulation by NO x , were key to a uniquely comprehensive combined composition-volatility description of OA. Our findings thus provide some of the most complete mechanistic-level guidance to the development of OA descriptions in air quality and Earth system models.
Databáze: MEDLINE