Prediction of air pollution frequency distribution — Part II. The Gaussian plume model

Abstract Hourly and daily averaged concentrations of SO 2 , measured from January until March 1973 at 125 sampling locations in the industrial Rijnmond region in the Netherlands, are compared with results of the Gaussian plume model. The average correlation coefficient between the observed and calculated time series is 0.3. The observed and calculated frequency distribution agree at the 50-percentile within a factor 2, when the background concentration is included in the calculations. For the higher percentiles such as the 98-percentile the deviations between calculated and observed results are approximately within a factor 4. The frequency distributions are also calculated with the aid of an empirical model. The results obtained with this model for the 98-percentile are better than those obtained with the Gaussian plume model.