Fine particulate pollution and ambient air quality: A case study over an urban site in Delhi, India

Abstract

Abstract: The current study discourses the impact of variation in PM2.5 concentration on the ambient air quality of Delhi. The 24-hourly PM2.5 concentration dataset was obtained from air quality measurement site (Anand Vihar) of Delhi Pollution Control Committee (DPCC) for the duration of April 2015 to December 2018. The annual and seasonal variability in the trend of ambient PM2.5 along with cumulative impact of meteorological parameters have been analyzed. The overall percentage increase in annual PM2.5 concentration, compared to National Ambient Air Quality Standards (NAAQS) guidelines, is observed to be 286.09%. The maximum concentration of fine particulate matter was recorded to be 788.6 µg/m3 during post-monsoon season and it was found to be associated with lower ambient temperature of 21.34°C and wind speed of 0.33 m/sec. Further, PM2.5 concentration was found to be correlated with CO (R = 0.6515) and NH3 (R = 0.6396) indicating similar sources of emission. Further, backward trajectory analysis revealed contribution in PM2.5 concentration from the states of Punjab and Haryana. The results indicated that particulate pollution is likely to occur in urban atmospheric environments with low temperatures and low wind speeds. Research highlights: PM2.5/PM10 ratio was observed to be highest in November, December and January, attributing aggravated levels of particle pollution to anthropogenic sources.Seasonal analysis of PM2.5 concentration indicated that particulate pollution was severe during post monsoon and winter months.Carbon monoxide (R = 0.6515; R2 = 0.4244) and Ammonia (R = 0.6396; R2 = 0.4088) were found to be correlated with PM2.5.Backward air mass trajectory depicted that air mass direction was coming to the receptor site (Anand Vihar) from the states of Haryana and Punjab. © 2020, Indian Academy of Sciences.