Skip to content

Mechanism reduction for the formation of secondary organic aerosol for integration into a 3-dimensional regional Air Quality Model: alpha-pinene oxidation system

by A G Xia, D V Michelangeli, P A Makar
Atmos Chem Phys Discuss ()
  • ISSN: 1680-7316


A detailed -pinene oxidation mechanism was reduced systematically through the successive application of five mechanism reduction techniques. The resulting reduced mechanism preserves the ozone- and organic aerosol-forming properties of the original mechanism, while using less species. The methodologies employed 5 included a directed relation graph method with error propagation (DRGEP, which removed a large number of redundant species and reactions), principal component analysis of the rate sensitivity matrix (PCA, used to remove unnecessary reactions), the quasi-steady-state approximation (QSSA, used to remove some QSS species), an iterative screening 10 method (ISSA, which removes redundant species and reactions simultaneously), and a new lumping approach dependant on the hydrocarbon to NOx ratio (which reduced the number of species in mechanism subsets for specific hydrocarbon to NOx ranges). This multistage methodology results in a reduction ratio of 2.5 for the number of both species and reactions compared with the full mechanism. The simplified mechanism 15 reproduces the important gas and aerosol phase species (the latter are examined in detail by individual condensing species as well as in classes according to four functional groups: PANs, nitrates, organic peroxides, and organic acids). The total SOA mass is also well represented in the condensed mechanism, to within 16% of the detailed mechanism under a wide range of conditions. The methodology described here is 20 general, and may be used in general mechanism reduction problems.

Cite this document (BETA)

Readership Statistics

5 Readers on Mendeley
by Discipline
40% Engineering
40% Environmental Science
20% Chemistry
by Academic Status
40% Student > Ph. D. Student
40% Researcher
20% Student > Doctoral Student

Sign up today - FREE

Mendeley saves you time finding and organizing research. Learn more

  • All your research in one place
  • Add and import papers easily
  • Access it anywhere, anytime

Start using Mendeley in seconds!

Sign up & Download

Already have an account? Sign in