An operational air pollution model using routine meteorological data.

Typ: Rapport
Serie: RMK 40
Författare: Omstedt, Gunnar


An operational air pollution model using routine meteorological data is described. An hourly time series of pollutant concentrations is calculated for emissions from one or several tall industrial stacks. New methods developed by Nielsen et al. (1981),. Berkowicz and Prahm (1982 a, b), Olesen et al.(1983) are used for determining boundary layer parameters i.e. surface sensible heat flux, friction velocity, mean wind speed and mixing height. These parameter values are used as input data to the dispersion part of the model. An updated Gaussian dispersion model, strongly supported by experimental data and similar to that developed by Weil and Bower (1982) is used. Briggs' dispersion parameters are used with the stability classification scheme based on the values of w*/u during daytime and Pasquill-Gifford-Turner classes during nighttime for selection of stability classes. Plume rise and plume penetration of elevated stable layers are calculated by formulae from Briggs (1975). A similar model will also be used in Denmark (Berkowicz et al., 1983). Examples of results are given, based on four years of hourly meteorological data and radiosonde data from Bromma airport in Stockholm. A tentative comparison between the present model and Högström's (1968) model is made for emission from a 500 MW power plant. This comparison indicates that Högström's model predicts ground level concentrations that are too high occurring too close to tall industrial stacks.