An averaging time model of SO2 frequency distributions from a single point source

Abstract

A model is proposed to estimate frequency distributions for SO2 concentrations due to an isolated point source and to estimate SO2 maxima at different averaging times, given the maximum at one averaging time. The model assumes (1) the air pollution data have an exponential distribution, (2) the maximum concentration is approximately inversely proportional to the averaging time raised to an exponent and (3) the observed arithmetic mean is the same at all averaging times. The model has been applied to the data sets from three stations monitoring SO2 concentrations from a power station in the Upper Hunter Valley in New South Wales. Australia, it is shown that the model performs better than other statistical models, and estimates maxima quite well for the 1 2-h, 1 -h and 3-h averaged data sets using the 8-h time averaged data set. The results using the 24-h time average values to reproduce shorter time averaged data were not satisfactory. Show more