Secondary organic aerosol reduced by mixture of atmospheric vapours
Journal article, 2019
Secondary organic aerosol contributes to the atmospheric particle burden with implications for air quality and climate. Biogenic volatile organic compounds such as terpenoids emitted from plants are important secondary organic aerosol precursors with isoprene dominating the emissions of biogenic volatile organic compounds globally. However, the particle mass from isoprene oxidation is generally modest compared to that of other terpenoids. Here we show that isoprene, carbon monoxide and methane can each suppress the instantaneous mass and the overall mass yield derived from monoterpenes in mixtures of atmospheric vapours. We find that isoprene ‘scavenges’ hydroxyl radicals, preventing their reaction with monoterpenes, and the resulting isoprene peroxy radicals scavenge highly oxygenated monoterpene products. These effects reduce the yield of low-volatility products that would otherwise form secondary organic aerosol. Global model calculations indicate that oxidant and product scavenging can operate effectively in the real atmosphere. Thus highly reactive compounds (such as isoprene) that produce a modest amount of aerosol are not necessarily net producers of secondary organic particle mass and their oxidation in mixtures of atmospheric vapours can suppress both particle number and mass of secondary organic aerosol. We suggest that formation mechanisms of secondary organic aerosol in the atmosphere need to be considered more realistically, accounting for mechanistic interactions between the products of oxidizing precursor molecules (as is recognized to be necessary when modelling ozone production).
Author
G. McFiggans
University of Manchester
Th. F. Mentel
Jülich Research Centre
J. Wildt
Jülich Research Centre
Iida Pullinen
Jülich Research Centre
Sungah Kang
Jülich Research Centre
Einhard Kleist
Jülich Research Centre
Sebastian Schmitt
Jülich Research Centre
Monika Springer
Jülich Research Centre
R. Tillmann
Jülich Research Centre
Cheng Wu
Jülich Research Centre
Defeng Zhao
Jülich Research Centre
Fudan University
Mattias Hallquist
University of Gothenburg
Cameron Faxon
University of Gothenburg
Michael Le Breton
University of Gothenburg
Åsa M. Hallquist
IVL Swedish Environmental Research Institute
David Simpson
Chalmers, Space, Earth and Environment, Microwave and Optical Remote Sensing
Robert Bergström
University of Gothenburg
SMHI
Chalmers, Space, Earth and Environment, Microwave and Optical Remote Sensing
M. E. Jenkin
Atmospheric Chemistry Services
Mikael Ehn
University of Helsinki
Joel A. Thornton
University of Washington
M. Rami Alfarra
University of Manchester
Thomas J. Bannan
University of Manchester
C. J. Percival
University of Manchester
Michael Priestley
University of Manchester
University of Gothenburg
D. Topping
University of Manchester
A. Kiendler-Scharr
Jülich Research Centre
Nature
0028-0836 (ISSN) 1476-4687 (eISSN)
Vol. 565 7741 587-593Atmospheric oxidation of stress induced emissions from vegetation - its role for aerosol formation
Formas (942-2015-1537), 2016-01-01 -- 2018-12-31.
ModElling the Regional and Global Earth system (MERGE)
Lund University (9945095), 2010-01-01 -- .
Subject Categories (SSIF 2011)
Meteorology and Atmospheric Sciences
Roots
Basic sciences
DOI
10.1038/s41586-018-0871-y
PubMed
30700872