@article {stlaurent_new_2023,
	title = {New insights on black carbon in pelagic Atlantic sediments},
	journal = {Marine Chemistry},
	year = {2023},
	month = {09/2023},
	pages = {104312},
	abstract = {Black carbon (BC) is ubiquitous in pelagic sediments and presumed to have an older radiocarbon age due to long ocean residence times and pre-aging in terrestrial soils. Here, we analyzed sediments from five regions in the subtropical Atlantic Ocean to quantify the black carbon fraction of the total organic carbon pool. Black carbon, derived from the chemothermal oxidation method, comprised between 17 {\textpm} 6\% of the sedimentary organic carbon in the Northwest Argentina Basin and 65 {\textpm} 18\% in the Amazon Delta. Black carbon sediment accumulation rates were six times greater in the Sierra Leone Rise (8.4 {\textpm} 4.1 mg cm-2 kyr-1) compared to the remote Northwest Argentina Basin (1.3 {\textpm} 0.4 mg cm-2 kyr-1), possibly due to enhanced regional atmospheric deposition from annual African grassland fires. The radiocarbon age for BC from subtropical Atlantic sediments were more modern compared to the bulk total organic carbon, and BC source was apportioned as biomass burning byproducts from their stable carbon isotopic signatures and characteristic ratios of polycyclic aromatic hydrocarbons. This study demonstrated that subtropical Atlantic Ocean sediments serve as an important sink for young BC.},
	keywords = {Atlantic Ocean, BLACK CARBON, Polycyclic aromatic hydrocarbons, radiocarbon, sediments},
	issn = {0304-4203},
	doi = {10.1016/j.marchem.2023.104312},
	url = {https://www.sciencedirect.com/science/article/pii/S0304420323001081},
	author = {St.Laurent, Kari and Cantwell, Mark and Lohmann, Rainer}
}
@article {2675,
	title = {Biomass-Derived Provenance Dominates Glacial Surface Organic Carbon in the Western HimalayaBiomass-Derived Provenance Dominates Glacial Surface Organic Carbon in the Western Himalaya},
	journal = {Environmental Science \& Technology},
	volume = {54},
	year = {2020},
	month = {Sep-07-2021},
	pages = {8612 - 8621},
	abstract = {The origin, transport pathway, and spatial variability of total organic carbon (OC) in the western Himalayan glaciers are poorly understood compared to those of black carbon (BC) and dust, but it is critically important to evaluate the climatic role of OC in the region. By applying the distribution of OC activation energy; C-14 activity; and radiogenic isotopes of Pb-208/Pb-204, (207)pb/(204)pb and (206)pb/Pb-204 in glacial debris and atmospheric particulate matter (PM10 size fraction), we demonstrate that 98.3 +/- 1.6 and 1.7 +/- 1.6\% of OC in western Himalayan glaciers are derived from biomass and petrogenic sources, respectively. The (delta C-13 and N/C composition indicates that the biomass is a complex mixture of C3 vegetation and autochthonous photoautotrophic input modified by heterotrophic microbial activity. The data set reveals that the studied western Himalayan glacier has negligible contributions from fossil-fuel- derived particles, which contrasts to the central and eastern Himalayan glaciers that have significant contributions from fossil fuel sources. We show that this spatial variability of OC sources relates to regional differences in air mass transport pathways and precipitation regimes over the Himalaya. Moreover, our observation suggests that biomass-derived carbon could be the only primary driver of carbon-induced glacier melting in the western Himalaya.},
	keywords = {; MASS BALANCES, AEROSOLS, ALBEDO REDUCTION, ATMOSPHERIC LEAD, BLACK CARBON, DUST TRANSPOR, isotopic composition, PB, SNOW ALBEDO, TIBETAN PLATEAU},
	issn = {0013-936X},
	doi = {10.1021/acs.est.0c0271010.1021/acs.est.0c02710.s001},
	url = {https://apps.webofknowledge.com/InboundService.do?product=WOS\&Func=Frame\&DestFail=http\%3A\%2F\%2Fwww.webofknowledge.com\&SrcApp=search\&SrcAuth=Alerting\&SID=8Aqj2WiW4A71bymjSli\&customersID=Alerting\&mode=FullRecord\&IsProductCode=Yes\&AlertId=ab9062f8-b111-4f95-},
	author = {Nizam, Sarwar and Sen, Indra S. and Vinoj, Velu and Galy, Valier and Selby, David and Azam, Mohammad F. and Pandey, Satyendra K. and Creaser, Robert A. and Agarwal, Avinash K. and Singh, Akhilendra P. and Bizimis, Michael}
}
@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 {1284,
	title = { Allochthonous sources and dynamic cycling of ocean dissolved organic carbon revealed by carbon isotopes},
	journal = {GEOPHYSICAL RESEARCH LETTERS},
	volume = {44},
	year = {2017},
	month = {03/2017},
	pages = {2407-2415},
	abstract = {We present concentration and isotopic profiles of total, size, and polarity fractionated dissolved organic carbon (DOC) from Station ALOHA (A Long-term Oligotrophic Habitat Assessment), an oligotrophic site in the North Pacific Ocean. The data show that, between the surface and 3500 m, low molecular weight (LMW) hydrophilic DOC, LMW hydrophobic DOC, and high molecular weight (HMW) DOC constitute 22-33\%, 45-52\%, and 23-35\% of DOC, respectively. LMW hydrophilic DOC is more isotopically depleted (delta C-13 of -23.9 parts per thousand to -31.5 parts per thousand and Delta C-14 of -304 parts per thousand to -795 parts per thousand; mean age of 2850 to 15000 years) than the LMW hydrophobic DOC (delta C-13 of -22 parts per thousand to -23 parts per thousand and Delta C-14 of -270 parts per thousand to -568 parts per thousand; 2470 to 6680 years) and HMW DOC (delta C-13 of similar to-21 parts per thousand and Delta C-14 of -24 parts per thousand to -294 parts per thousand; 135-2700 years). Our analyses suggest that a large fraction of DOC may be derived from allochthonous sources such as terrestrial and hydrothermal DOC and cycle on much longer time scales of > 10000 years or enter the ocean as preaged carbon.},
	keywords = {ATLANTIC BIGHT, BLACK CARBON, C-14, HUMIC SUBSTANCES, MATTER, NORTH PACIFIC-OCEAN, RADIOCARBON ANALYSIS, SARGASSO SEA, SEAWATER, SPECTROMETRY},
	doi = {10.1002/2016GL071348},
	author = {Zigah, Prosper K. and McNichol, Ann P. and Xu, Li and Johnson, Carl and Santinelli, Chiara and Karl, David M. and Repeta, Daniel J.}
}
@article {1841,
	title = {Source apportionment of elevated wintertime PAHs by compound-specific radiocarbon analysis},
	journal = {Atmospheric Chemistry and Physics},
	volume = {9},
	year = {2009},
	note = {452qjTimes Cited:22
Cited References Count:52
},
	month = {2009},
	pages = {3347-3356},
	abstract = {Natural abundance radiocarbon analysis facilitates distinct source apportionment between contemporary biomass/biofuel ((14)C "alive") versus fossil fuel ((14)C "dead") combustion. Here, the first compound-specific radiocarbon analysis (CSRA) of atmospheric polycyclic aromatic hydrocarbons (PAHs) was demonstrated for a set of samples collected in Lycksele, Sweden a small town with frequent episodes of severe atmospheric pollution in the winter. Renewed interest in using residential wood combustion (RWC) means that this type of seasonal pollution is of increasing concern in many areas. Five individual/paired PAH isolates from three pooled fortnight-long filter collections were analyzed by CSRA: phenanthrene, fluoranthene, pyrene, benzo[b+k] fluoranthene and indeno[cd]pyrene plus benzo[ghi]perylene; phenanthrene was the only compound also analyzed in the gas phase. The measured Delta(14)C for PAHs spanned from -138.3\% to 58.0\%. A simple isotopic mass balance model was applied to estimate the fraction biomass (fbiomass) contribution, which was constrained to 71-87\% for the individual PAHs. Indeno[cd]pyrene plus benzo[ghi]perylene had an fbiomass of 71\%, while fluoranthene and phenanthrene (gas phase) had the highest biomass contribution at 87\%. The total organic carbon (TOC, defined as carbon remaining after removal of inorganic carbon) fbiomass was estimated to be 77\%, which falls within the range for PAHs. This CSRA data of atmospheric PAHs established that RWC is the dominating source of atmospheric PAHs to this region of the boreal zone with some variations among RWC contributions to specific PAHs.},
	keywords = {air-pollution sources, atmospheric aerosols, BLACK CARBON, emissions, northern sweden, organic-compounds, particulate matter, polycyclic aromatic-hydrocarbons, positive matrix factorization, residential wood combustion},
	isbn = {1680-7316},
	author = {Sheesley, R. J. and Krusa, M. and Krecl, P. and Johansson, C. and Gustafsson, O.}
}
@article {2446,
	title = {Method for determining coal carbon in the reclaimed minesoils contaminated with coal},
	journal = {Soil Science Society of America Journal},
	volume = {72},
	year = {2008},
	note = {24},
	month = {Jan-Feb},
	pages = {231-237},
	abstract = {Minesoils are anthropic soils developed on land disturbed by mining activities. Minesoils developed on the reclaimed surface-mined sites for coal are contaminated with coal particles resulting from mining and reclamation activities. Therefore, the total organic carbon (TOC) pool in these sites is a mixture of coal and plant-derived recent soil organic carbon (SOC). Accurate estimates of SOC pools and C sequestration rates in the reclaimed minesoils (RMS) is limited by the lack of a standard and cost-effective method for determination of coal C concentrations in the RMS. The chemi-thermal method, based on the oxidative resistance of coal, was developed and validated with radiocarbon analysis using selected artificial soil-coal mixtures and minesoil samples. Radiocarbon analysis of RMS samples indicated that minesoils from the top 10-cm depth developing from topsoil applied during reclamation was coal C free. The contribution of coal C and the radiocarbon age of TOC increased with increasing soil depth. The coal C fraction accounted for 0 to 92\% of TOC in the RMS samples. The coal C fraction was highly correlated with delta C-13 (r(2) = 0.84), suggesting that stable isotope composition could estimate the coal C concentration in RMS samples. Analysis of coal and artificial soil and coal mixtures indicated that chemi-thermal treatment was effective in removing recent SOC with minimum effect on coal. Analysis of RMS samples indicated that both radiocarbon activity and the chemi-thermal method were effective in estimating coal C concentration in RMS of southeast Ohio. The coal C concentrations for both methods were highly correlated (r(2) = 0.95), suggesting that the chemi-thermal method was as effective as radiocarbon activity measurement in estimating coal C concentration in these soils.},
	keywords = {BLACK CARBON, C-14, FOREST, GENESIS, MATTER, MINING DISTRICT, RICH MINE SOILS, sediments, SITES, SOIL ORGANIC-CARBON},
	isbn = {0361-5995},
	doi = {10.1016/j.dsr2.2008.07.005},
	author = {Ussiri, D. A. N. and Lai, R.}
}
@article {2049,
	title = {Characterization of Siberian Arctic coastal sediments: Implications for terrestrial organic carbon export},
	journal = {Global Biogeochemical Cycles},
	volume = {18},
	year = {2004},
	note = {806knTimes Cited:99
Cited References Count:51
},
	month = {Mar 10},
	abstract = {Surface sediments were collected during the 2000 TransArctic Expedition along the Siberian Arctic coastline, including the Ob, Yenisey, Khatanga, Lena, and Indigirka estuaries. Sediments were characterized for elemental composition (total organic carbon, TOC, black carbon, BC, and total N, as well as major and trace elements), isotopic signature (delta(13)C, delta(15)N, Delta(14)C, epsilon(Nd), Sr-87/Sr-86), and organic molecular composition to better understand river export variations over the large spatial scale of the Siberian Arctic. On average, 79 +/- 9\% of the total C in sediments was organic while 21 +/- 9\% was inorganic. BC made up 9 +/- 4\% of the TOC pool, with a general increasing trend from west to east along the Siberian coast. The combined Nd- and Sr-isotopes (epsilon(Nd) and Sr-87/Sr-86) were used to define two distinct sediment sources between east and west Siberian regions with the Khatanga River as a boundary. Data from pyrolysis-GC/MS of the sedimentary organic carbon (SOC) indicated an increase in the freshness of the organic matter from west to east on the Siberian Arctic coast, with increasing relative abundance of furfurals (polysaccharides) with respect to nitriles. Values for the delta(13)C of SOC ranged from -27.1\% (mostly terrigenous) to -23.8\%, while delta(15)N increased from east to west (3.1 to 5.2\%) with a significant correlation with C/N ratio. Values for the Delta(14)C of SOC ranged from -805 to -279\%, with a consistent trend increasing from the east (Indigirka River) to the west (Ob River). These D 14 C values corresponded to a 14 C age of 2570 +/- 30 yBP in the Ob estuary and 13,050 +/- 50 yBP in the Indigirka estuary. Most importantly, D 14 C values were significantly correlated with the ratio of BC/TOC (R-2 = 0.91, n = 6), consistent with the distribution pattern of increasing permafrost zone from the west to the east along the Siberian coast. Together, our results suggest that older OC was derived from the release of recalcitrant BC during permafrost thawing and riverbank and coastal erosion, likely enhanced by ongoing environmental changes in the northern ecosystem.},
	keywords = {arctic ocean, BLACK CARBON, climate, CO2, continental-shelf, flux, isotopic composition, lena river, MATTER, ocean, organic carbon, quantification, Sediment},
	isbn = {0886-6236},
	doi = {10.1029/2003GB002087},
	url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2\&amp;SrcAuth=Alerting\&amp;SrcApp=Alerting\&amp;DestApp=WOS\&amp;DestLinkType=FullRecord;UT=WOS:000220432900001},
	author = {Guo, L. D. and Semiletov, I. and Gustafsson, O. and Ingri, J. and Andersson, P. and Dudarev, O. and White, D.}
}
