Quantitative assessment of the emitted criteria pollutant in Delhi urban area

Abstract

The compositions of the emitted criteria pollutant from the anthropogenic sources are investigated in the present study for Delhi urban area. The quantitative study of various types of the criteria pollutants, i.e., Carbon Monoxide (CO), Nitrogen Oxide (NOx) and Particulate Matter (PM) emitting from various sources is carried out. The primary emitting sources of these criteria pollutants are the vehicles, industries, power plants, domestic and dust sources. The estimated emissions depends a number of factors such as fuel consumption, technological developments, industrial activity and other activities that cause air pollutions. The analysis shows that CO, NOx and PM emissions are mainly contributed by vehicular sources. The results of the present study are found to be well compared to those reported in literature. The estimated emissions are also shown by spatial variations isopleths over 26 km × 30 km gridded area of Delhi. The concentrations of these pollutants are predicted by using the emissions and meteorological variables as the input in AERMOD, an USEPA’s dispersion model. Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of ± 32% for NOx to a high of ± 235% for CO. Quantile-Quantile (Q-Q) plots and statistical performance have also been analyzed and it is observed that the predicted concentrations of CO, NOx and PM are in good agreement with respect to observed values. Further, in some locations the predicted concentrations are much higher than the permissible National Ambient Air Quality Standards (NAAQS) levels. These locations are ITO junction, DCE, ISBT Kashmere Gate, Dhaula Kuan, Indraprashta and Badarpur. Thus, this study shows high air pollution load in Delhi and degrading the ambient air quality creates many environmental problems.