This project supports an NSF Postdoctoral Research Fellow to investigate the atmospheric chemistry of biogenic isoprene emissions. Isoprene can be produced by terrestrial ecosystems and can react differently in the atmosphere depending on what other gases and aerosols are present. Nitrogen oxide concentrations can influence the extent to which isoprene contributes to the formation of ozone or very small organic particles in the atmosphere.
This research investigates isoprene oxidation processes in conditions with low concentrations of nitrogen oxides (NOx), and the effects of isoprene oxidation products on ozone and the formation of secondary organic aerosol (SOA). The focus is on the formation, destruction and physical uptake processes of hydroperoxides. The research is expected to address long-standing questions about hydrogen peroxide deposition rates and its impact on the budget of hydrogen oxide radicals (HOx), and lead to new parameterizations based on in-situ data. The contribution of isoprene to SOA formation will be investigated by examining the sources and sinks of each oxidation reaction across a wide variety of environmental conditions. A novel instrument will be deployed for the separation of isoprene oxidation products to examine the different chemical fates of each.