Combining Models for Assessment of Local Air Quality

Abstract

Assessing local air quality can be a challenging task. Indeed, local air quality is strongly dependent on local factors but also regional and in some cases even global effects have to be taken into account when assessing local air pollution concentrations. Furthermore, large gradients in pollutant concentrations can be present in the urban environment. In order to assess the local air quality for the city of Antwerp, a combination of an Eulerian dispersion model, a measurement interpolation tool, a Gaussian plume model and a simplified version of the OSPM street canyon model have been coupled to each other, taking into account double counting effects of local emissions. The coupled model which combines the regional, urban and street canyon scale has been applied for the city centre of Antwerp and its harbour. This results in detailed maps with a resolution up to 30 m for four pollutants: PM₁₀, PM_2.5, EC (elementary carbon) and NO₂. Furthermore, several abatement measures have been assessed in order to improve the urban air quality. It has been shown that local (traffic) measures only have a small effect on total mass PM₁₀ and PM_2.5 concentrations, but exhibit a larger effect on EC and NO₂-concentrations.