Air pollution is the result of human activities in twentieth century which has direct and indirect effects on human being and its environment. Environmental researchers and human ecologists have studied air pollution quantitave analysis and forecasting. Time series analysis is a method to study time fluctuation in natural events. The importance of time study of air pollution is its effect on human health. In this study time series of daily concentration of SO2، O3، TSP، NO2،NO ، CO، CH4 and NMVOC from Isfahan petrochemical industry is studied. Autocorrelation functions of the series showed that SO2, O3 and NO2 are independent from time and are purely random. The result of regression also showed non linear dynamic of pollutants through time which can be the result of seasonal impacts. Spectral density function and cumulative normal plot also indicate non linear and seasonal fluctuations.
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