气候变化领域集成服务门户(CCPortal): Three North African dust source areas and their geochemical fingerprint

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DOI	10.1016/j.epsl.2020.116645
	Three North African dust source areas and their geochemical fingerprint
	Jewell A.M.; Drake N.; Crocker A.J.; Bakker N.L.; Kunkelova T.; Bristow C.S.; Cooper M.J.; Milton J.A.; Breeze P.S.; Wilson P.A.
发表日期	2021
ISSN	0012821X
卷号	554
英文摘要	North Africa produces more than half of the world's atmospheric dust load. Once entrained into the atmosphere, this dust poses a human health hazard locally. It also modifies the radiative budget regionally, and supplies nutrients that fuel primary productivity across the North Atlantic Ocean and as far afield as the Amazonian Basin. Dust accumulation in deep sea and lacustrine sediments also provides a means to study changes in palaeoclimate, particularly those associated with rainfall climate change. Systematic analysis of satellite imagery has greatly improved our understanding of the trajectories of long-range North African dust plumes, but our knowledge of the dust-producing source regions and our ability to fingerprint their contribution to these export routes is surprisingly limited. Here we report new radiogenic isotope (Sr and Nd) data for sediment samples from known dust-producing substrates (dried river and lake beds), integrate them with published isotope data and weight them for dust source activation. We define three isotopically distinct preferential dust source areas (PSAs): a Western, a Central and an Eastern North African PSA. More data are needed, particularly from the Western PSA, but our results show a change in PSA dust source composition to more radiogenic Nd- and less radiogenic Sr-isotope values from west to east, in line with the overall decreasing age of the underlying bedrock. Our data reveal extreme isotopic heterogeneity within the Chadian region of the Central PSA, including an extremely distinctive geochemical fingerprint feeding the Bodélé Depression, the most active dust source on Earth. Our new analysis significantly improves the reliability by which windblown dust deposits can be geochemically fingerprinted to their distant source regions. © 2020 Elsevier B.V.
关键词	87Sr/86Sr Bodélé Depression dust source North Africa radiogenic isotopes εNd
英文关键词	Budget control; Climate change; Geochemistry; Health hazards; Image enhancement; Isotopes; Reliability analysis; Satellite imagery; Sediments; Dust accumulation; Dust source areas; Geochemical fingerprints; Lacustrine sediments; North Atlantic Ocean; Primary productivity; Radiogenic isotopes; Systematic analysis; Dust; aerosol composition; atmospheric transport; dust; geochemistry; long range transport; point source; radionuclide; satellite imagery; substrate; Atlantic Ocean; Atlantic Ocean (North); Bodele; Chad; North Africa
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203151
作者单位	University of Southampton, National Oceanography Centre Southampton, Waterfront Campus, European Way, Southampton, SO14 3ZH, United Kingdom; Department of Geography, Bush House North East Wing, Kings College London, London, WC2B 4BG, United Kingdom; Department of Archaeology, Max Planck Institute for the Science of Human History, Kahlaische Strasse 10, Jena, D-07745, Germany; Department of Earth and Planetary Sciences, Birkbeck University of London, Malet Street, London, WC1E 7HX, United Kingdom
推荐引用方式 GB/T 7714	Jewell A.M.,Drake N.,Crocker A.J.,et al. Three North African dust source areas and their geochemical fingerprint[J],2021,554.
APA	Jewell A.M..,Drake N..,Crocker A.J..,Bakker N.L..,Kunkelova T..,...&Wilson P.A..(2021).Three North African dust source areas and their geochemical fingerprint.Earth and Planetary Science Letters,554.
MLA	Jewell A.M.,et al."Three North African dust source areas and their geochemical fingerprint".Earth and Planetary Science Letters 554(2021).