The role of volatile organic compounds in the polluted urban atmosphere of Bristol, England

[摘要] The results of a field campaign carried out from early spring through to the late summer of2000, in Bristol, England, are presented.Continuous measurements of over 40 hydrocarbonshave been made at an urban background site, located at Bristol University, for approximatelynine months using a Gas Chromatography - Flame Ionisation Detection (GC-FID) system andfor a selection of halocarbons for approximately one month using a Gas Chromatography- Electron Capture Detection (GC-ECD) system.In this paper we present the time-series of thenine halocarbons and selected hydrocarbons.Daytime and night-time hydroxyl radicalconcentrations have been estimated based on the diurnal variations of a selection of themeasured hydrocarbons.The average summer daytime concentration of OH was found to be2.5x10⁶ molecules cm^-3 and the night-time concentration to be in the range10⁴ to 10⁵ molecules cm^-3.In addition, the role played by certain VOCs in the formation of ozone isassessed using the POCP (Photochemical Ozone Creation Potential) concept.

[学科分类] 大气科学