ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-11-227-2011 Tracer concentration profiles measured in central London as part of the REPARTEE campaign Martin D. 1 3 Petersson K. F. 1 White I. R. 1 Henshaw S. J. 1 Nickless G. 1 Lovelock A. 1 Barlow J. F. 2 Dunbar T. 2 Wood C. R. 2 Shallcross D. E. 1 School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK Department of Meteorology, University of Reading, Reading, RG6 6BB, UK now at: Centre for Climate and Air Pollution Studies, National University of Ireland Galway, Galway, Ireland 12 01 2011 11 1 227 239 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/11/227/2011/acp-11-227-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/11/227/2011/acp-11-227-2011.pdf

There have been relatively few tracer experiments carried out that have looked at vertical plume spread in urban areas. In this paper we present results from two tracer (cyclic perfluorocarbon) experiments carried out in 2006 and 2007 in central London centred on the BT Tower as part of the REPARTEE (Regent's Park and Tower Environmental Experiment) campaign. The height of the tower gives a unique opportunity to study vertical dispersion profiles and transport times in central London. Vertical gradients are contrasted with the relevant Pasquill stability classes. Estimation of lateral advection and vertical mixing times are made and compared with previous measurements. Data are then compared with a simple operational dispersion model and contrasted with data taken in central London as part of the DAPPLE campaign. This correlates dosage with non-dimensionalised distance from source. Such analyses illustrate the feasibility of the use of these empirical correlations over these prescribed distances in central London.

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