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Bohnenstegel_Clearflo_BAMS_2015.pdf (4.92 MB)

Meteorology, Air Quality, and Health in London: The ClearfLo Project

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posted on 2019-09-30, 11:33 authored by SI Bohnenstengel, SE Belcher, A Aiken, JD Allan, G Allen, A Bacak, TJ Bannan, JF Barlow, DCS Beddows, WJ Bloss, AM Booth, C Chemel, O Coceal, CF Di Marco, MK Dubey, KH Faloon, ZL Fleming, M Furger, JK Gietl, RR Graves, DC Green, CSB Grimmond, CH Halios, JF Hamilton, RM Harrison, MR Heal, DE Heard, C Helfter, SC Herndon, RE Holmes, JR Hopkins, AM Jones, FJ Kelly, S Kotthaus, B Langford, JD Lee, RJ Leigh, AC Lewis, RT Lidster, FD Lopez-Hilfiker, JB McQuaid, C Mohr, PS Monks, E Nemitz, NL Ng, CJ Percival, ASH Prevot, HMA Ricketts, R Sokhi, D Stone, JA Thornton, AH Tremper, AC Valach, S Visser, LK Whalley, LR Williams, L Xu, DE Young, P Zotter
Air quality and heat are strong health drivers, and their accurate assessment and forecast are important in densely populated urban areas. However, the sources and processes leading to high concentrations of main pollutants, such as ozone, nitrogen dioxide, and fine and coarse particulate matter, in complex urban areas are not fully understood, limiting our ability to forecast air quality accurately. This paper introduces the Clean Air for London (ClearfLo; project’s interdisciplinary approach to investigate the processes leading to poor air quality and elevated temperatures. Within ClearfLo, a large multi-institutional project funded by the U.K. Natural Environment Research Council (NERC), integrated measurements of meteorology and gaseous, and particulate composition/loading within the atmosphere of London, United Kingdom, were undertaken to understand the processes underlying poor air quality. Long-term measurement infrastructure installed at multiple levels (street and elevated), and at urban background, curbside, and rural locations were complemented with high-resolution numerical atmospheric simulations. Combining these (measurement–modeling) enhances understanding of seasonal variations in meteorology and composition together with the controlling processes. Two intensive observation periods (winter 2012 and the Summer Olympics of 2012) focus upon the vertical structure and evolution of the urban boundary layer; chemical controls on nitrogen dioxide and ozone production—in particular, the role of volatile organic compounds; and processes controlling the evolution, size, distribution, and composition of particulate matter. The paper shows that mixing heights are deeper over London than in the rural surroundings and that the seasonality of the urban boundary layer evolution controls when concentrations peak. The composition also reflects the seasonality of sources such as domestic burning and biogenic emissions.


ClearfLo is funded by NERC under Grant NE/H00324X/1 (lead proposal) and is coordinated by NCAS. Grant references for split awards are NE/H003169/1, NE/H003150/1, NE/H003177/1, NE/H003207/1, NE/H003185/1, NE/H003223/1, NE/H00324X/1, NE/H003193/1, NE/H003231/1, and NE/H003142/1. Funding for the FAAM aircraft was provided by NERC Grant Reference NE/I021276/1. We thank the flight operations team and aircrew from NERC Airborne Research and Survey Facility for providing access to the Dornier 228 aircraft and for providing support to Project: GB12/09. Thanks go to the Chelsea and Kensington council, which granted us access to the Trellick, Dartrey, and Grenfell towers (Adrian Bowman and Kyri Eleftheriou-Vaus, Royal Borough Kensington and Chelsea). Thanks also go to Islington Borough. Thanks go to BT for supporting instrument deployment on BT Tower (Bob Semon, Wayne Loeber, Andy Beale, and Eric Anderson). We thank Steve Neville of Westminster City Council for permission to use its building as a measurement site. Thanks to John Lally for technical support throughout, and to Barbara Brooks and James Groves for technical support during the intensive observation periods. We thank the Sion Manning School and the adjacent community center. We thank Dr. Paul Smith and Lukas Pauscher for putting in the BLS, LAS, and ceilometers and communications infrastructure on the towers. We thank Roger Moore and his staff at the Kent Showground, Detling, for help with installing and operating the Detling winter IOP site. We acknowledge the participation of the following in the winter IOP measurements at Detling: John Jayne, Andrew Freedman, William Brooks, Jonathan Franklin, Paola Massoli, Edward Fortner, Puneet Chhabra, Mark Zahnizer, Harald Stark, and Douglas Worsnop (Aerodyne Research, Inc.); W. Berk Knighton (Montana State University); Kyle Gorkowski (Los Alamos National Laboratory, United States); and Timothy Martin and Richard Coulter (Argonne National Laboratory, United States). Funding



Bulletin of the American Meteorological Society, 2015, 96 (5), pp. 779-804 (26)

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/Organisation/COLLEGE OF SCIENCE AND ENGINEERING/Department of Physics and Astronomy


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A supplement to this article is available online (10.1175/BAMS-D-12-00245.2)



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