@article {2777,
	title = {Dual-Isotope Constraints on Seasonally Resolved Source Fingerprinting of Black Carbon Aerosols in Sites of the Four Emission Hot Spot Regions of China},
	journal = {Journal of Geophysical Research: Atmospheres},
	volume = {123},
	year = {2018},
	month = {Mar-10-2020},
	pages = {11,735 - 11,747},
	abstract = {Despite much recent efforts, the emission sources of black carbon (BC) aerosols--central input to understanding and predicting environmental and climate impact--remain highly uncertain. Here we present observational δ13C/Δ14C-based constraints on the sources of BC aerosols over the four seasons in each of the four key hot spot emission regions of China: Beijing-Tianjin-Hebei (BTH-Wuqing; where Wuqing is the sampling location), Yangtze River Delta (YRD-Haining), Pearl River Delta (PRD-Zhongshan), and Sichuan Basin (SC-Deyang). Overall, BC loadings were highest in winter, yet elevated loadings were also observed in other seasons, for example, spring at SC-Deyang and fall at PRD-Zhongshan. Annually, the dominant BC sources were coal (50 {\textpm} 20\%) for BTH-Wuqing, liquid fossil for YRD-Haining (46 {\textpm} 8\%) and PRD-Zhongshan (48 {\textpm} 18\%), whereas liquid fossil (42 {\textpm} 17\%) and biomass burning (41 {\textpm} 14\%) equally affected SC-Deyang. There is also different but distinct seasonalities in BC sources for the different sites. As an example, for BTH-Wuqing coal burning increased from summer to winter, while summer and spring BTH-Wuqing were more influenced by liquid fossil. In contrast, for YRD-Haining, the relative importance of emission sources was more constant over the year. These quantitative observational constraints on source-seasonality of BC aerosols in receptor sites located in China{\textquoteright}s four key economic zones highlight that regulatory control on BC aerosol emissions from different fuels should consider both seasonal and regional variations. Our results also suggest that models on estimates of BC-induced climate and air quality should consider variations over both regional and seasonal scales.},
	keywords = {aerosol, BLACK CARBON, carbon isotope, china, emission sources, seasonality},
	doi = {10.1029/2018JD028607},
	url = {http://doi.wiley.com/10.1029/2018JD028607},
	author = {Fang, Wenzheng and Du, Ke and Andersson, August and Xing, Zhenyu and Cho, Chaeyoon and Kim, Sang-Woo and Deng, Junjun and Gustafsson, {\"O}rjan}
}
@article {2778,
	title = {Divergent Evolution of Carbonaceous Aerosols during Dispersal of East Asian Haze},
	journal = {Scientific Reports},
	volume = {7},
	year = {2017},
	month = {Jan-12-2017},
	abstract = {Wintertime East Asia is plagued by severe haze episodes, characterized by large contributions of carbonaceous aerosols. However, the sources and atmospheric transformations of these major components are poorly constrained, hindering development of efficient mitigation strategies and detailed modelling of effects. Here we present dual carbon isotope (δ13C and Δ14C) signatures for black carbon (BC), organic carbon (OC) and water-soluble organic carbon (WSOC) aerosols collected in urban (Beijing and BC for Shanghai) and regional receptors (e.g., Korea Climate Observatory at Gosan) during January 2014. Fossil sources (>50\%) dominate BC at all sites with most stemming from coal combustion, except for Shanghai, where liquid fossil source is largest. During source-to-receptor transport, the δ13C fingerprint becomes enriched for WSOC but depleted for water-insoluble OC (WIOC). This reveals that the atmospheric processing of these two major pools are fundamentally different. The photochemical aging (e.g., photodissociation, photooxidation) during formation and transport can release CO2/CO or short-chain VOCs with lighter carbon, whereas the remaining WSOC becomes increasingly enriched in δ13C. On the other hand, several processes, e.g., secondary formation, rearrangement reaction in the particle phase, and photooxidation can influence WIOC. Taken together, this study highlights high fossil contributions for all carbonaceous aerosol sub-compartments in East Asia, and suggests different transformation pathways for different classes of carbonaceous aerosols.},
	doi = {10.1038/s41598-017-10766-4},
	url = {http://www.nature.com/articles/s41598-017-10766-4},
	author = {Fang, Wenzheng and Andersson, August and Zheng, Mei and Lee, Meehye and Holmstrand, Henry and Kim, Sang-Woo and Du, Ke and Gustafsson, {\"O}rjan}
}
