Investigating the potential importance of primary NO\(_2\) emissions in a street canyon
research
NOx
street canyon
air quality modelling
Modelling and measurement study investigating whether directly emitted (primary) NO2 from road vehicles is an important contributor to NO2 concentrations within a street canyon environment.
Investigating the potential importance of primary NO\(_2\) emissions in a street canyon
Atmospheric Environment, 2004
Monitoring data from a busy street canyon in central London and a paired background site are used to investigate the potential importance of primary (directly emitted) NO2 from road vehicles. Multiple regression is used to estimate the fraction of NO2 in petrol and diesel exhaust emissions. Results suggest that petrol and diesel vehicles emit approximately 0.6 ± 0.2 and 12.7 ± 0.1 vol% NO2 respectively. Primary emissions of this magnitude appear to explain much of the observed difference in NO2 concentrations between the street canyon and background sites, and have important implications for how NO2 concentrations respond to NOx emission controls and for source apportionment modelling studies.