A second generation Gaussian dispersion model: the POLARIS model
The development of a second generation Gaussian dispersion model (POLARIS) has been carried out. This model is significantly different from traditional Gaussian dispersion models, because its dispersion parameters have a continuous variation with the atmospheric stability. The new model was applied to the region of Setubal. The fossil fuel power plant in this region was taken as a point source, and data from 1993 were used. The results obtained using POLARIS were compared with air quality data and with results obtained from the POLUX and ISCST models for the same conditions. In terms of the statistical parameters, NMSE (normalised mean square error) and correlation coefficients, it can be seen that POLARIS gives the best approximation to the measured data. It also can be seen that POLARIS provides more results within a 'factor of two', related to the measured concentrations, than the other two models for Setubal case.
Keywords: atmospheric dispersion models, field data, Gaussian models, second generation models, air pollution, environmental pollution, modelling, Portugal, fossil fuel, power plants