Ozone and aerosol productivity of reactive organics

Abstract

A technique developed to determine the amount of ozone and secondary photochemical species generated by the individual organic components of a complex atmospheric organic/NOₓ mixture (Bowman and Seinfeld, J. geophys. Res. 99, 5309–5324 (1994a)) is used to study the individual contributions of carbonyl, aromatic, alkane, and alkene emissions to ozone and secondary organic and inorganic aerosol species in the South Coast Air Basin of California for the Southern California Air Quality Study (SCAQS) air pollution episode of 27–28 August 1987. Aldehydes exhibit the highest ozone productivity followed by alkenes, and lumped reactive aromatics. The aromatic species and formaldehyde enhance the production of secondary organic and secondary sulfate aerosol, because they are effectively OH sources. The same species, through their effect on both OH and O₃ production, are also significant precursors of HNO₃, and consequently, of nitrate aerosol. This methodology can be used in conjunction with urban airshed models to investigate alternative emission control scenarios.