VOCs as indicators of halogen chemistry during ARCTAS A and OASIS
Abstract
Two experiments, the 2008 aircraft-based, NASA-led ARCTAS campaign, and the 2009 ground-based (Barrow, AK), NSF-sponsored OASIS campaign were conducted, in part, to gain a better understanding of Arctic boundary layer chemistry. A wide range of non-methane hydrocarbons, oxygenated volatile organic compounds, and halocarbons were measured during each campaign using in-situ GC-MS (Gas Chromatograph-Mass Spectrometer), PTR-MS (Proton transfer mass spectrometry), and canister collection followed by laboratory GC analysis, significantly expanding the spatial and temporal database of these compounds in the Arctic spring-time marine boundary layer. Widespread ozone depletion was observed throughout the Arctic Ocean boundary layer during ARCTAS and numerous ODEs were observed during the OASIS study. A combination of measurements and simple modeling of VOC species that have characteristic reaction rates with the oxidants, Br, Cl, and OH, indicative of halogen chemistry, was used to put limits on the mixing ratios of atomic chlorine and bromine during these events. Measurements of acetaldehyde were investigated and compared in the context of previous measurements and PAN formation. Results were checked for self-consistency with ClO (Barrow only), Cl2 (Barrow only), BrO, and HOx species (OH, HO2, and RO), taking advantage of the first time that these species have been measured (and co-measured with the VOCs) in the Arctic Ocean environment.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2009
- Bibcode:
- 2009AGUFM.A32B..03A
- Keywords:
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- 0365 ATMOSPHERIC COMPOSITION AND STRUCTURE / Troposphere: composition and chemistry