Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 10 2 2010 10.5194/acp-10-627-2010 http://www.atmos-chem-phys.net/10/627/2010/ http://www.atmos-chem-phys.net/10/627/2010/acp-10-627-2010.html http://www.atmos-chem-phys.net/10/627/2010/acp-10-627-2010.pdf 627 645 2010-01-22 Fluxes and concentrations of volatile organic compounds above central London, UK B. Langford b.langford1@lancaster.ac.uk E. Nemitz E. House G. J. Phillips D. Famulari B. Davison J. R. Hopkins A. C. Lewis C. N. Hewitt Lancaster Environment Centre, Lancaster University, LA1 4YQ, Lancaster, UK Biogeochemistry Programme, Centre for Ecology and Hydrology (Edinburgh), Bush Estate, EH26 0QB, Penicuik, UK School of Chemistry, Edinburgh University, West Mains Road, EH9 3JJ, Edinburgh, UK National Centre for Atmospheric Science, University of York, YO10 5DD, York, UK Concentrations and fluxes of eight volatile organic compounds (VOCs) were measured during October 2006 from a high telecom tower above central London, as part of the CityFlux contribution to the REPARTEE I campaign. A continuous flow disjunct eddy covariance technique with analysis by proton transfer reaction mass spectrometry was used. Daily averaged VOC mixing ratios were within the range 1–19 ppb for the oxygenated compounds (methanol, acetaldehyde and acetone) and 0.2–1.3 ppb for the aromatics (benzene, toluene and C₂-benzenes). Typical VOC fluxes were in the range 0.1–1.0 mg m^−2 h^−1. 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