Journal cover Journal topic
Geoscientific Model Development An interactive open-access journal of the European Geosciences Union
Geosci. Model Dev., 8, 3231-3245, 2015
https://doi.org/10.5194/gmd-8-3231-2015
© Author(s) 2015. This work is distributed under
the Creative Commons Attribution 3.0 License.
Development and technical paper
13 Oct 2015
Analysis of the impact of inhomogeneous emissions in the Operational Street Pollution Model (OSPM)
T.-B. Ottosen1,2, K. E. Kakosimos1, C. Johansson3,5, O. Hertel4, J. Brandt4, H. Skov2,4, R. Berkowicz4, T. Ellermann4, S. S. Jensen4, and M. Ketzel4 1Department of Chemical Engineering, Texas A&M University at Qatar, Doha, Qatar
2Department of Chemical Engineering, Biotechnology and Environmental Technology, University of Southern Denmark, Odense, Denmark
3Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm, Sweden
4Department of Environmental Science, Aarhus University, Roskilde, Denmark
5Environment and Health Administration, Stockholm, Sweden
Abstract. Semi-parameterized street canyon models, as e.g. the Operational Street Pollution Model (OSPM®), have been frequently applied for the last two decades to analyse levels and consequences of air pollution in streets. These models are popular due to their speed and low input requirements. One often-used simplification is the assumption that emissions are homogeneously distributed in the entire length and width of the street canyon. It is thus the aim of the present study to analyse the impact of this assumption by implementing an inhomogeneous emission geometry scheme in OSPM. The homogeneous and the inhomogeneous emission geometry schemes are validated against two real-world cases: Hornsgatan, Stockholm, a sloping street canyon; and Jagtvej, Copenhagen; where the morning rush hour has more traffic on one lane compared to the other. The two cases are supplemented with a theoretical calculation of the impact of street aspect (height / width) ratio and emission inhomogeneity on the concentrations resulting from inhomogeneous emissions. The results show an improved performance for the inhomogeneous emission geometry over the homogeneous emission geometry. Moreover, it is shown that the impact of inhomogeneous emissions is largest for near-parallel wind directions and for high aspect ratio canyons. The results from the real-world cases are however confounded by challenges estimating the emissions accurately.

Citation: Ottosen, T.-B., Kakosimos, K. E., Johansson, C., Hertel, O., Brandt, J., Skov, H., Berkowicz, R., Ellermann, T., Jensen, S. S., and Ketzel, M.: Analysis of the impact of inhomogeneous emissions in the Operational Street Pollution Model (OSPM), Geosci. Model Dev., 8, 3231-3245, https://doi.org/10.5194/gmd-8-3231-2015, 2015.
Publications Copernicus
Download
Short summary
Semi-parameterised street canyon models are popular due to their speed and low input requirements. One often-used assumption is that emissions are homogeneously distributed in the entire length and width of the street. It is thus the aim of the present study to analyse the impact of this assumption by implementing an inhomogeneous emission geometry scheme and validating it. The results show an improved performance, however, confounded by challenges in estimating the emissions accurately.
Semi-parameterised street canyon models are popular due to their speed and low input...
Share