Extending the Use of Proton-Transfer-Reaction Mass Spectrometer (PTR-MS) for New Measurements of Volatile Organic Compounds and Their Oxidation Products

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

A Proton-Transfer-Reaction Mass Spectrometer (PTR-MS) instrument will be purchased and used for real-time, in-situ measurements of concentrations and fluxes of volatile organic compounds (VOCs), in particular, terpenes. These compounds play an important role in the tropospheric photochemistry of forested regions. In situ concentrations and flux measurements carried out with the PTR-MS coupled to the eddy covariance method will be compared to measurements using gas chromatography coupled to relaxed eddy accumulation. Extension to ecosystem scale fluxes will be attempted. The PTR-MS will also be used for in situ measurements of oxidation products of terpenes. In addition, the PI will collaborate with the research group of Prof. John Seinfeld at Caltech on laboratory studies of VOC oxidation processes by using the PTR-MS as a product analysis tool.