Abstract:
To regulate the effect of industrial emissions on ambient air quality standards, it is important to know about the dispersion of pollutants through air pollution models. In the present study, the information on source emission and meteorological data and the details of study area were collected. The contour maps for the distribution of SO2 and NO2 were generated during winter under maximum temperature conditions by using ISCST3 and AERMOD models over a period of five years. AERMOD has been used to analyze 24-hr maximum SO2 and NO2 concentrations downwind for all the five major industries studied (near Wipro Infotech Ltd.) over a period of five years during winter season and compared with the values obtained from ISCST3 model under similar conditions. The results indicated that AERMOD is slightly under-predicted the ground level pollutant concentration when compared to ISCST3. This may be due to the fact that unlike ISCST3, AERMOD calculates mixing height and stability class based on meteorological parameters such as; cloud cover, temperature, wind velocity and solar incidence angle and it is not artificially varied or kept constant throughout the model run. Whereas, in ISCST3 model run, the stability class and mixing heights were kept constant throughout.

Keywords: Ambient air quality, emission inventory, air quality prediction models, ISCST3.