Characteristics, seasonality and sources of carbonaceous and ionic components in the tropical aerosols from Indian region
Item
Title (Dublin Core)
Characteristics, seasonality and sources of carbonaceous and ionic components in the tropical aerosols from Indian region
Description (Dublin Core)
To better characterize the tropical aerosols in Indian region, PM<sub>10</sub> samples collected from Chennai, India (13.04° N; 80.17° E) were analyzed for carbonaceous and water-soluble ionic components. Concentration ranges of elemental carbon (EC) and organic carbon (OC) were 2.4–14 μg m<sup>−3</sup> (ave. 6.5 μg m<sup>−3</sup>) and 3.2–15.6 μg m<sup>−3</sup> (ave. 9.1 μg m<sup>−3</sup>) in winter samples whereas they were 1.1–2.5 μg m<sup>−3</sup> (ave. 1.6 μg m<sup>−3</sup>) and 4.1–17.6 μg m<sup>−3</sup> (ave. 9.7 μg m<sup>−3</sup>) in summer samples, respectively. Concentration of secondary organic carbon (SOC) retrieved from EC-tracer method was 4.6±2.8 μg m<sup>−3</sup> in winter and 4.3±2.8 μg m<sup>−3</sup> in summer. OC accounted for 38.5±14 % (<i>n</i> = 49) of combined concentrations of carbonaceous and ionic components in PM<sub>10</sub>. We also found that OC concentrations are generally higher than those of SO<sub>4</sub><sup>2−</sup> (8.8±2.5 μg m<sup>−3</sup> and 4.1±2.7 μg m<sup>−3</sup> in winter and summer, respectively), which was the most abundant ionic species (57 %) followed by NH<sub>4</sub><sup>+</sup> (15 %) >NO<sub>3</sub><sup>−</sup>>Cl<sup>−</sup>>K<sup>+</sup>>Na<sup>+</sup>> Ca<sup>2+</sup>>MSA<sup>−</sup>>Mg<sup>2+</sup>. The mass fractions of EC, organic matter (OM) and ionic species varied seasonally, following the air mass trajectories and corresponding source strength. Based on mass concentration ratios of selected components and relations of EC and OC to marker species, we found that biofuel/biomass burning is a major source of atmospheric aerosols in South and Southeast Asia. The high concentrations of SOC and WSOC/OC ratios (ave. 0.45; <i>n</i> = 49) as well as good correlations between SOC and WSOC suggest that the secondary production of organic aerosols during long-range atmospheric transport is also significant in this region. This study provides the baseline data of carbonaceous aerosols for southern part of the Indian subcontinent.
Creator (Dublin Core)
Pavuluri, C. M.
Kawamura, K.
Aggarwal, S. G.
Swaminathan, T.
Date (Dublin Core)
2018-01-15
Type (Dublin Core)
Text
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
10.5194/acp-11-8215-2011
https://acp.copernicus.org/articles/11/8215/2011/
Source (Dublin Core)
eISSN: 1680-7324
Language (Dublin Core)
eng
