Environmental Science and Engineering Seminar

Chemical transformations in the atmosphere control the distribution of pollutants that impact air quality, human health, and the climate. A key class of such chemical transformations is the oxidation of volatile organic compounds (VOCs) which impacts both ozone production and the formation of secondary organic aerosol (SOA). Each generation of VOC oxidation is initiated by an oxidant to form an organic peroxy radical (RO2) which can then react with several bimolecular reaction partners or undergo unimolecular isomerization. As such, atmospherically relevant laboratory studies must match both the distribution of oxidants and RO2 fates in the global atmosphere. Here we present a new approach for laboratory studies of atmospheric SOA production, using isoprene as a model system. Our approach uses global modeling with GEOSChem to understand the distribution of oxidants and RO2 fates in the atmosphere followed by box modeling of laboratory conditions to assess how experiments can be designed to match atmospheric conditions. With this approach, we are able to run our laboratory experiments under more realistic atmospheric conditions than are typically accessed.