Despite continued research activity aimed at understanding isoprene behavior, oxidative pathways involving this critical and ubiquitous photochemical ozone precursor remain rather poorly constrained mechanistically. This proposal follows on from the Principal Investigator's previous work in laboratory and theoretical investigations of the temperature- and pressure-dependant oxidation rates and nitrate yields of isoprene and select alkene model systems under low- and high- reactive oxidized nitrogen (NOx) conditions typical of the ambient troposphere. Another aspect of this project will involve mining existing ambient data sets from several past programs that acquired field measurements under NOx-limited photochemical regimes and using a chemical coordinate analysis approach to assess consistency and mechanistic accuracy in these previous findings.
Results from this study will provide substantial new insights into the mechanisms of climatically important alkene chemistry and photochemical cycling, reconcile or at least constrain some current uncertainties in how models treat these systems, and in doing so lead to a better understanding of factors contributing to the formation and accumulation of tropospheric ozone. The broader educational impacts of this work include support for two graduate students who will gain professional research training and experience under the mentorship of the PI. Summer undergraduate students will also be involved in this research performing interpretive data analyses through a Research Experiences for Undergraduates (REU) activity.
