title: Atmospheric carbonaceous aerosols from Indo-Gangetic Plain and Central Himalaya: impact of anthropogenic sources.
abstract: In the present-day scenario of growing anthropogenic activities, carbonaceous aerosols contribute significantly (∼20-70%) to the total atmospheric particulate matter mass and, thus, have immense potential to influence the Earth's radiation budget and climate on a regional to global scale. In addition, formation of secondary organic aerosols is being increasingly recognized as an important process in contributing to the air-pollution and poor visibility over urban regions. It is, thus, essential to study atmospheric concentrations of carbonaceous species (EC, OC and WSOC), their mixing state and absorption properties on a regional scale. This paper presents the comprehensive data on emission sources, chemical characteristics and optical properties of carbonaceous aerosols from selected urban sites in the Indo-Gangetic Plain (IGP) and from a high-altitude location in the central Himalaya. The mass concentrations of OC, EC and WSOC exhibit large spatio-temporal variability in the IGP. This is attributed to seasonally varying emissions from post-harvest agricultural-waste burning, their source strength, boundary layer dynamics and secondary aerosol formation. The high concentrations of OC and SO4(2-), and their characteristic high mass scattering efficiency, contribute significantly to the aerosol optical depth and scattering coefficient. This has implications to the assessment of single scattering albedo and aerosol radiative forcing on a regional scale.
authors.affiliation: Physical Research Laboratory, Ahmedabad 380009, India; Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221 005, India. Electronic address: ram.iesd@bhu.ac.in.
authors.forename: Kirpa
authors.initials: K
authors.lastname: Ram
authors.affiliation: Physical Research Laboratory, Ahmedabad 380009, India. Electronic address: sarin@prl.res.in.
authors.forename: M M
authors.initials: MM
authors.lastname: Sarin
mesh_terms: D000336:Aerosols / Q000032:analysis*; D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution; D000531:Altitude; D002244:Carbon / Q000032:analysis; D002980:Climate; D003247:Conservation of Natural Resources; D004784:Environmental Monitoring / Q000379:methods*; D040362:Geographic Information Systems; D006801:Humans; D007194:India; D052638:Particulate Matter / Q000032:analysis; D012621:Seasons; D013431:Sulfates / Q000032:analysis
chemical_list: D000336:Aerosols; D000393:Air Pollutants; D052638:Particulate Matter; D013431:Sulfates; D002244:Carbon
keywords: Biomass burning; Carbonaceous aerosols; Central Himalaya; Indo-Gangetic plain; Organic, elemental carbon