Overview of ClearfLo: Study of Aerosol Sources and Processing at a Rural Site Southeast of London, January-February, 2012
Authors
Leah R Williams — Aerodyne Research Inc
Scott C Herndon — Aerodyne Research, Inc.
John T Jayne — Aerodyne Research, Inc.
Andrew Freedman — Aerodyne Research, Inc.
William Brooks — Aerodyne Research, Inc.
Jonathan P Franklin — Aerodyne Research, Inc.
Paola Massoli — Aerodyne Research, Inc.
Ed Fortner — Aerodyne Research, Inc.
Puneet Chhabra — Aerodyne Research, Inc.
Mark Stuart Zahniser — Aerodyne Research, Inc.
Harald Stark — Aerodyne Research, Inc.
Timothy B Onasch — Aerodyne Research
Douglas R Worsnop — Aerodyne Research
Felipe Lopez-Hilfiker — University of Washington
Claudia Mohr — University of Washington
Joel Thornton — University of Washington
Nga Lee Ng — Georgia Institute of Technology
Lu Xu — Georgia Institute of Technology
Walter Berkett Knighton — Montana State University
Manvendra K. Dubey — Los Alamos National Laboratory
Allison C Aiken — Los Alamos National Laboratory
Kyle Gorkowski — Los Alamos National Laboratory
Shang Liu — Los Alamos National Laboratory
Timothy J. Martin — Argonne National Laboratory
Richard L. Coulter — Argonne National Laboratory
Suzanne Visser — Paul Scherrer Institut
Markus Furger — Paul Scherrer Institute
Peter Zotter — Paul Scherrer Institute
André Prévôt — Paul Scherrer Institute
Category
Secondary Organic Aerosol
Description
Clean Air for London (ClearfLo) was a large, multidisciplinary study of the London urban atmosphere aimed at understanding the relationships between surface meteorology, gas-phase composition and particulate matter from multiple sites: at a city street site (London), a city background site (away from local traffic sources in London) and at rural locations (outflow from the London urban area). We deployed a suite of instruments at the rural site approximately 50 km southeast of London in Detling, UK during January-February, 2012. Measurements included aerosol chemical, optical and microphysical properties, gas-phase tracers, secondary organic aerosol (SOA) precursors, and radiative and meteorological conditions. During the six week campaign, we sampled air masses from several distinct sources. Winds from the southwest passed over a large road 200 m from the site and brought air masses characterized by highly variable CO, indicating local sources, high black carbon concentrations, and hydrocarbon-like aerosol chemical composition. When the wind was from the east and northeast, we sampled outflow from the European continent. The gas-phase composition indicated an aged air mass, and particle composition was predominately oxygenated organics, nitrate and sulfate. Outflow from London was sampled during periods when the wind was from the northwest. In addition to regional air quality, the winter time study provided information on gas and particle emissions from local home heating with solid fuels. We will present case studies of different particle sources, including a comparison of chemistry and optical properties, as well as comparisons with urban London particulate measurements.Lead PI
Leah R Williams — Aerodyne Research Inc