Carbonaceous Aerosol Characterization and Their Relationship With Meteorological Parameters During Summer Monsoon and Winter Monsoon at an Industrial Region in Delhi, India

Abstract

AbstractPM10 samples were collected and atmospheric organic carbon (OC) and elemental carbon (EC) were determined during summer monsoon (SM) and winter monsoon (WM) seasons in 2016–2017 at an industrial location in New Delhi, India. Owing to high combustion and emission activities in the industrial area, it was imperative to characterize the carbonaceous aerosols, including their morphology and seasonal distribution. The mean PM10 concentration was 144 ± 53.7 and 210.4 ± 50.7 μg/m3 in SM and WM, respectively, with an overall average of 174.6 ± 64 μg/m3. Moreover, the OC concentration was 70.3 ± 53.7 and 94.3 ± 40.3 μgC/m3 during the SM and WM, respectively, with an overall average of 79.9 ± 44.9 μgC/m3, and the EC concentration was 50.8 ± 53 and 62.6 ± 49.8 μgC/m3, respectively, with an overall average of 58.3 ± 46.7 μgC/m3. The morphological observations of collected particles were studied and the char/soot particles, iron‐rich particles, and aggregates of calcium sulfate particles were observed during both the seasons. However, the predominance of combustion‐derived particles such as soot and char was higher in the WM than in the SM. Further, the OC/EC ratio suggested the presence of mixed sources at the industrial location, predominated by industry and motor vehicle emissions. The relationship of carbonaceous aerosol with meteorological variables was also studied, and it was found that temperature, atmospheric stability, wind direction, and rain intensity significantly affect the levels of OC as compared to that of EC during both seasons.