Evaluation of the street level air quality (SLAQ) model for carbon monoxide

Abstract

This project discusses the evaluation of an emission-dispersion model for predicting the temporal and spatial distribution of vehicle-derived pollution in street canyons. The model is called Street Level Air Quality (SLAQ). The model was developed at the University of Nottingham by Micallef and Coils in 1998. SLAQ is semi-empirical, in that it uses not only results from field and wind tunnel experiments but also theory and models derived from multiple runs of numerical routines in order to simulate the basic physical processes within the street canyon. SLAQ has been evaluated for carbon monoxide in Jagtvej, a street in Copenhagen, Denmark. For this evaluation, two sets of data were available. One set of data corresponds to 1994, while the other to 1995. The data sets include meteorological data, measurements of street geometry, background carbon monoxide concentration, traffic data and carbon monoxide concentration measured within the street. The analysis is carried out for 1994, 1995 and for the two combined years. When the results from SLAQ are compared with the presented measurements, correlation coefficients of around 0.9 between the modelled and measured concentrations have been obtained.