Seasonal characteristics of water-soluble inorganic ions and carbonaceous aerosols in total suspended particulate matter at a rural semi-arid site, Kadapa (India)

Abstract

To better understand the sources as well as characterization of regional aerosols at a rural semi-arid region Kadapa (India), size-resolved composition of atmospheric particulate matter (PM) mass concentrations was sampled and analysed. This was carried out by using the Anderson low-pressure impactor for a period of 2 years during March 2013-February 2015. Also, the variations of organic carbon (OC), elemental carbon (EC) and water-soluble inorganic ion components (WSICs) present in total suspended particulate matter (TSPM) were studied over the measurement site. From the statistical analysis, the PM mass concentration showed a higher abundance of coarse mode particles than the fine mode during pre-monsoon season. In contrast, fine mode particles in the PM concentration showed dominance over coarse mode particle contribution during the winter. During the post-monsoon season, the percentage contributions of coarse and fine fractions were equal, whereas during the monsoon, coarse mode fraction was approximately 26 % higher than the fine mode. This distinct feature in the case of fine mode particles during the studied period is mainly attributed to large-scale anthropogenic activities and regional prevailing meteorological conditions. Further, the potential sources of PM have been identified qualitatively by using the ratios of certain ions. A high sulphate (SO) concentration at the measurement site was observed during the studied period which is caused by the nearby/surrounding mining activity. Carbon fractions (OC and EC) were also analysed from the TSPM, and the results indicated (OC/EC ratio of ~4.2) the formation of a secondary organic aerosol. At last, the cluster backward trajectory analyses were also performed at Kadapa for different seasons to reveal the origin of sources from long-range transport during the study period.

Seasonal variation and sources of carbonaceous species and elements in PM2.5 and PM10 over the eastern Himalaya

“…Several studies conducted in past on carbonaceous aerosols, inorganic aerosols and elements in particulate matter and their potential sources in urban (Ram and Sarin, 2011;Mandal et al 2014;Sharma et al 2016;Gupta et al 2018;Shivani et al 2019;Jain et al 2020a;, rural, remote (Begam et al 2017) as well as high altitude atmosphere (Ram et al 2008;Kumar and Attri, 2016;Sarkar et al 2017;Kaushal et al 2018) but very limited study (Sharma et al 2020b) has been conducted in the eastern Himalayan region of India. Considering the importance of atmospheric carbonaceous species and elements in PM2.5 and PM10 and from their perspective on climate change, the present study has been carried out at Darjeeling (the eastern Himalaya).…”

Chemical Characteristics of Aerosols from Distinct Environments over the Indian Region: Heterogeneity in Distribution and Sources of Carbonaceous Aerosols

“…Large-scale agricultural residue burning over upper IGP also accounted for the increased OC emissions. , During the winter period, the presence of shallow boundary height and favorable meteorological conditions (low temperature and wind speed) are conducive for the production of secondary OC, which contributes to the fog-haze weather conditions in IGP . Over continental regions, low concentrations of OC and EC were seen over remote sites such as high-altitude regions Langtang, Nepal (OC: 1.81 μg m –3 , EC: 0.52 μg m –3 ), and island locations Hanimaadhoo (OC: 1.22 μg m –3 ; EC: 0.58 μg m –3 ) and Malé (OC: 1.88 μg m –3 ; EC: 0.76 μg m –3 ) in Maldives. , Except for the coastal industrial site COK, all of the other sites in southern peninsular India like TVM (OC: 11.8 μg m –3 ), CBE (OC: 10.4 μg m –3 ), Chennai (OC: 9.1 μg m –3 ), and Kadapa (OC: 11 μg m –3 ) had nearly similar winter average OC concentrations. EC concentrations over TVM (EC: 3.1 μg m –3 ) and Kadapa (EC: 3.9 μg m –3 ) were found to be similar.…”

The removal of atmospheric aerosols in a heavy industrial coastal city in China with frequent rainfall

“…The NO − 3 =SO 2− 4 ratio of the atmospheric aerosols is recognized as an effective approach to assessing stationary and mobile sources of nitrogen and sulfur and has been widely used at various locations around the world (Arimoto et al, 1996;Tan et al, 2009;Safai et al, 2010;Begam et al, 2017). When this ratio is > 1, the emissions are considered to be produced by mobile sources; otherwise, they are emitted from stationary sources…”