Articles | Volume 26, issue 6
https://doi.org/10.5194/acp-26-4173-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-26-4173-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Technical note
| 
25 Mar 2026
Technical note |
| 25 Mar 2026
| 25 Mar 2026
Technical note: Comparing ozone production efficiency (OPE) of chemical mechanisms using chemical process analysis (CPA)
Ramboll, 7250 Redwood Blvd., Suite 105, Novato, CA 94945, USA
Alan M. Dunker
A. M. Dunker, LLC, 4041 Vendome Drive, Auburn Hills, MI 48326, USA
Greg Yarwood
Ramboll, 7250 Redwood Blvd., Suite 105, Novato, CA 94945, USA
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Secondary organic aerosols are an important component of PM2.5, with contributions from anthropogenic, biogenic volatile organic compounds, semi- and intermediate volatility organic compounds. Policy makers need to know which SOA precursors are important. We investigated the role of different SOA precursors and SOA algorithms by applying two commonly used models, CAMx and CMAQ. Suggestions for SOA modelling and control are provided.
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Short summary
Gas-phase chemical mechanisms are key components of air quality models used by regulatory agencies for air quality and public health planning. We use modeled ozone concentrations and Ozone Production Efficiency (OPE) to compare four chemical mechanisms and find that OPE is a viable comparison metric under atmospheric conditions where nitrogen oxides are limited. Using OPE to predict how ozone responds to emissions reductions, however, is an oversimplification that can overstate ozone reductions.
Gas-phase chemical mechanisms are key components of air quality models used by regulatory...
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