Nonmethane Hydrocarbons Measurements in Vancouver Region during Pacific 2001 Study
Abstract
Nonmethane hydrocarbons \(NMHCs\) and carbonyl compounds constitute important precursors of free radicals, which govern atmospheric photochemical processes. To investigate the impact of these radical precursors on regional photochemistry, diurnal cycles of NMHCs and carbonyls were studies during 10-31 August at several sites as part of the Pacific 2001 field study in the Vancouver region, British Columbia, Canada. The mixing ratios for total NMHCs exhibited strong diurnal patterns and varied from 1 to 20 parts per billion \(ppb\). For sites near forests, the dominant NMHCs were isoprene and the monoterpenes of alpha-pinene and beta-pinene. The maximum values reached nearly 3 ppb These species exhibited strong diel cycles, owing to the interactions between local emissions and chemical sinks. In this presentation, the focus will be on these biogenic hydrocarbons to ascertain their relative importance on the photochemical activity experienced in the airshed of Vancouver. Results from the 2001 field campaign will be integrated with long-term records of biogenic hydrocarbons for the region with the view to elucidate the time of year when biogenic compounds can be more effective in contributing to regional oxidant production.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2002
- Bibcode:
- 2002AGUFM.A71A0088W
- Keywords:
-
- 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE