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DOI	10.3189/172756406781812122
	Elemental and organic carbon measurements with a two-step heating-gas chromatography system in snow samples from the Tibetan Plateau
	Xu, Baiqing; Yao, Tandong; Liu, Xianqin; Wang, Ninglian
发表日期	2006
ISSN	0260-3055
起始页码	257
结束页码	+
卷号	43
英文摘要	In this study, an optimized two-step heating-gas chromatography system is used to measure elemental carbon (EC) and organic carbon (OC) content in snow and ice, with the ability to quantify the elemental and organic carbon species in a snow or ice sample of 60-80 g. in this system, OC and EC are transformed into CO2 in a stream of oxygen at 340 degrees C and 650 degrees C, respectively. The resulting CO2 is accumulated in two molecular-sieve traps, and then put into a gas chromatograph equipped with a flame ionization detector by heating the traps to 200 degrees C in a helium stream. Background contamination (mainly caused by impurities in the oxygen stream) and accuracy are dominated by the variability of the blank loads on the pre-cleaned filters, which are 0.50 +/- 0.04 (1 sigma) mu gC for OC, and 0.38 +/- 0.04 (1 sigma) mu gC for EC. The system is suitable for snow and ice sample measurements, with the same precision as shown for the blank tests. EC and OC concentrations have been measured in snow samples collected from different glaciers on the Tibetan Plateau. The results allow quantification for the first time of the different carbonaceous particle contents on the Tibetan Plateau and other regions. The concentrations of EC and OC particles in snow show a clearly decreasing trend from east to west and from north to south on the plateau, excluding the Pamirs region. The highest mean EC content, 79.2 ng g(-1), was found in the northeast region, and the lowest, 4.3 ng g(-1), was found in the western Himalaya. We note that even slight surface melting results in fresh snow getting dirtier, especially in regions with higher pollution such as seen on a glacier in the Qilian Shan. Here, the EC and OC concentrations in the fresh snow average 6.6 and 87.Sngg-1, but after 2days of surface melting they increased to 52.6 and 195.5 ng g(-1). This suggests that surface snow melting can reduce snow albedo due to the accumulation of carbonaceous particles.
关键词	BLACK CARBON AEROSOLS CLIMATE SOOT ATMOSPHERE RECORD
学科领域	Geology
语种	英语
WOS研究方向	Geology
WOS类目	Geosciences, Multidisciplinary
WOS记录号	WOS:000245520800037
来源期刊	ANNALS OF GLACIOLOGY, VOL 43, 2006
来源机构	中国科学院青藏高原研究所
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/111463
推荐引用方式 GB/T 7714	Xu, Baiqing,Yao, Tandong,Liu, Xianqin,et al. Elemental and organic carbon measurements with a two-step heating-gas chromatography system in snow samples from the Tibetan Plateau[J]. 中国科学院青藏高原研究所,2006,43.
APA	Xu, Baiqing,Yao, Tandong,Liu, Xianqin,&Wang, Ninglian.(2006).Elemental and organic carbon measurements with a two-step heating-gas chromatography system in snow samples from the Tibetan Plateau.ANNALS OF GLACIOLOGY, VOL 43, 2006,43.
MLA	Xu, Baiqing,et al."Elemental and organic carbon measurements with a two-step heating-gas chromatography system in snow samples from the Tibetan Plateau".ANNALS OF GLACIOLOGY, VOL 43, 2006 43(2006).