@conference {958,
	title = {Year-round probing of soot carbon and secondary organic carbon contributions and sources to the South Asian Atmospheric Brown Cloud using radiocarbon (14C) measurements},
	booktitle = {EGU General Assembly 2010, held 2-7 May, 2010 in Vienna, Austria},
	volume = {12},
	year = {2010},
	note = {id: 870Y},
	month = {05/2010},
	abstract = {South Asia is one region of vital importance for assessing human impact on radiative forcing by atmospheric aerosols. Previous research in the region has indicated that black carbon is a significant component of the regional aerosol load. In contrast, there is more ambiguous information regarding the contribution of secondary organic aerosols (SOA) to the total carbonaceous (TC) aerosol composition. Here we primarily address the SOA component of the South Asian Atmospheric Brown Cloud (ABC) by a combination of measurements of SOA concentrations and the 14C signature of TC. Atmospheric particulate matter was collected during fourteen-month continuous sampling campaigns Jan 2008 - March 2009 at both the Maldives Climate Observatory at Hannimaadho (MCO-H) and at the Sinhagad hilltop sampling site of the Indian Institute of Tropical Meteorology (SIN) in central-western India. The radiocarbon method is an ideal approach to identify fossil sources (14C "dead") compared to biogenic and biomass combustion products (with a contemporary 14C signal). The radiocarbon source apportionment of TC revealed very similar contribution from biogenic/biomass combustion (60-70\%) for Indian SIN site and the MCOH receptor regions for much of the year. However, during the summer monsoon season biomass contribution to TC at the Indian Ocean site increases to 70-80\%, while it decreases to 40-50\% at the Indian site. Source apportionment of a soot carbon (SC) isolate (CTO-375 method; a tracer of black carbon) shows a similar trend. According to preliminary data in summer biomass contribution is higher at the MCOH receptor site (70\%) compared to the SIN background site (45\%). These unique year-round 14C data will be interpreted in view of the SOA concentration and the varying origin of the air masses.},
	author = {Kirillova, Elena and Sheesley, Rebecca J. and Andersson, August and Krus{\r a}, Martin and Safai, P. D. and Budhavant, Krishnakant and Rao, P. S. P. and Praveen, P. S. and Gustafsson, {\"O}rjan}
}
@article {332,
	title = {Brown Clouds over South Asia: Biomass or Fossil Fuel Combustion?},
	journal = {Science},
	volume = {323},
	year = {2009},
	note = {id: 1867; 396JL Times Cited:8 Cited References Count:33Y},
	pages = {495-498},
	abstract = {Carbonaceous aerosols cause strong atmospheric heating and large surface cooling that is as important to South Asian climate forcing as greenhouse gases, yet the aerosol sources are poorly understood. Emission inventory models suggest that biofuel burning accounts for 50 to 90\% of emissions, whereas the elemental composition of ambient aerosols points to fossil fuel combustion. We used radiocarbon measurements of winter monsoon aerosols from western India and the Indian Ocean to determine that biomass combustion produced two- thirds of the bulk carbonaceous aerosols, as well as one- half and two- thirds of two black carbon subfractions, respectively. These constraints show that both biomass combustion ( such as residential cooking and agricultural burning) and fossil fuel combustion should be targeted to mitigate climate effects and improve air quality.},
	issn = {0036-8075},
	doi = {10.1126/science.1164857},
	author = {Gustafsson, O. and Krusa, M. and Zencak, Z. and Sheesley, R. J. and Granat, L. and Engstrom, E. and Praveen, P. S. and Rao, P. S. P. and Leck, C. and Rodhe, H.}
}
