This project will develop a chemical ionization mass spectrometry (CIMS) system using isotope dilution for the in situ determination of peroxides in the atmosphere with a 10 Hz time resolution. The instrument will be certified for use on research aircraft including the NSF Gulfstream-V (GV). It will provide a new tool to address a number of unresolved scientific questions surrounding the atmospheric chemistry of peroxides. The fast response of this instrument will also allow flux studies of peroxides in the troposphere, significantly improving our understanding of hydroperoxide deposition and odd-hydrogen loss in the continental and marine boundary layers. Using the GV platform, the instrument will aid in quantifying hydrogen peroxide and methylhydroperoxide distributions in the upper troposphere, lower stratosphere and tropical tropopause layer and assess their transport and chemistry associated with deep convection. Finally, the fast instrument will have a response time sufficient to enable detailed studies of cloud processes affecting the peroxides. With cloud penetrations lasting only a few seconds, current instruments are too slow to resolve clouds, let alone resolve sub-cloud processes.
In addition to producing a new in situ measurement capability that significantly enhances the chemistry package for future airborne scientific missions, the project will involve undergraduate students and a post-doctoral scholar in the instrument development, improving their research skill sets in instrument development for atmospheric measurements. The post-doctoral scholar will also gain valuable experience by teaching an undergraduate chemistry class while being mentored by faculty at the U.S. Naval Academy.
