title: Local and regional components of aerosol in a heavily trafficked street canyon in central London derived from PMF and cluster analysis of single-particle ATOFMS spectra.
abstract: Positive matrix factorization (PMF) has been applied to single particle ATOFMS spectra collected on a six lane heavily trafficked road in central London (Marylebone Road), which well represents an urban street canyon. PMF analysis successfully extracted 11 factors from mass spectra of about 700,000 particles as a complement to information on particle types (from K-means cluster analysis). The factors were associated with specific sources and represent the contribution of different traffic related components (i.e., lubricating oils, fresh elemental carbon, organonitrogen and aromatic compounds), secondary aerosol locally produced (i.e., nitrate, oxidized organic aerosol and oxidized organonitrogen compounds), urban background together with regional transport (aged elemental carbon and ammonium) and fresh sea spray. An important result from this study is the evidence that rapid chemical processes occur in the street canyon with production of secondary particles from road traffic emissions. These locally generated particles, together with aging processes, dramatically affected aerosol composition producing internally mixed particles. These processes may become important with stagnant air conditions and in countries where gasoline vehicles are predominant and need to be considered when quantifying the impact of traffic emissions.
authors.affiliation: †Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy.|‡National Centre for Atmospheric Science, School of Geography, Earth and Environmental Sciences, Division of Environmental Health and Risk Management, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
authors.forename: Chiara
authors.initials: C
authors.lastname: Giorio
authors.affiliation: †Dipartimento di Scienze Chimiche, Università degli Studi di Padova, Via Marzolo 1, 35131 Padova, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Tapparo
authors.affiliation: §Institut de Ciències del Mar, CSIC, Pg Marı́tim de la Barceloneta 37-49, 08003 Barcelona, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Dall'Osto
authors.affiliation: ‡National Centre for Atmospheric Science, School of Geography, Earth and Environmental Sciences, Division of Environmental Health and Risk Management, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
authors.forename: David C S
authors.initials: DC
authors.lastname: Beddows
authors.affiliation: ‡National Centre for Atmospheric Science, School of Geography, Earth and Environmental Sciences, Division of Environmental Health and Risk Management, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.
authors.forename: Johanna K
authors.initials: JK
authors.lastname: Esser-Gietl
authors.affiliation: ∥Southern Ontario Centre for Atmospheric Aerosol Research, University of Toronto, Toronto, Canada.
authors.forename: Robert M
authors.initials: RM
authors.lastname: Healy
authors.affiliation: ‡National Centre for Atmospheric Science, School of Geography, Earth and Environmental Sciences, Division of Environmental Health and Risk Management, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom.|⊥Department of Environmental Sciences/Center of Excellence in Environmental Studies, King Abdulaziz University, Jeddah, 21589, Saudi Arabia.
authors.forename: Roy M
authors.initials: RM
authors.lastname: Harrison
mesh_terms: D000336:Aerosols / Q000032:analysis; D000393:Air Pollutants / Q000032:analysis*; D064751:Ammonium Compounds / Q000032:analysis; D002244:Carbon / Q000032:analysis; D016000:Cluster Analysis; D004784:Environmental Monitoring / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D008131:London; D013058:Mass Spectrometry; D018986:Motor Vehicles; D009930:Organic Chemicals / Q000032:analysis; D010316:Particle Size; D052638:Particulate Matter / Q000032:analysis*; D014507:Urbanization
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D064751:Ammonium Compounds; D009930:Organic Chemicals; D052638:Particulate Matter; D002244:Carbon