AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Effect of Photochemical Aging of 2-Methyltetrol on the Ambient Environment
ALISON FANKHAUSER, V. Faye McNeill, Columbia University
Abstract Number: 652 Working Group: Aerosol Chemistry
Abstract 2-Methyltetrol (2-MT) is a trace compound found in ambient aerosol particles and an important tracer species for isoprene photooxidation and aqueous secondary organic aerosol formation. However, very little is known about the rates, mechanisms, and products of the photochemical aging of this species in the atmosphere. Kinetic insights from photochemical aging experiments of 2-MT in aqueous sulfate particles were incorporated into GAMMA (Gas-Aerosol Model for Mechanism Analysis), a photochemical box model with coupled gas-phase chemistry and detailed aqueous aerosol chemistry [McNeill et al. 2012]. The original model was modified to allow for gas-particle partitioning of 2-MT, which is controlled by an experimentally determined effective Henry’s Law constant. Furthermore, as indicated by our experiments, particle-phase oxidation is represented as a surface reaction, which is controlled by an experimentally determined reactive uptake coefficient. This allows for the extrapolation of our laboratory results to relevant atmospheric conditions. We will present predictions on the impact of photochemical aging of 2-MT on the ambient environment.