气候变化领域集成服务门户(CCPortal): Glacial history of Inglefield Land; north Greenland from combined in situ 10Be and 14C exposure dating

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DOI	10.5194/cp-16-1999-2020
	Glacial history of Inglefield Land; north Greenland from combined in situ 10Be and 14C exposure dating
	Sofie Søndergaard A.; Krog Larsen N.; Steinemann O.; Olsen J.; Funder S.; Lundbek Egholm D.; Henrik Kjær K.
发表日期	2020
ISSN	18149324
起始页码	1999
结束页码	2015
卷号	16 期号:5
英文摘要	Determining the sensitivity of the Greenland Ice Sheet (GrIS) to Holocene climate changes is a key prerequisite for understanding the future response of the ice sheet to global warming. In this study, we present new information on the Holocene glacial history of the GrIS in Inglefield Land, north Greenland. We use 10Be and in situ 14C exposure dating to constrain the timing of deglaciation in the area and radiocarbon dating of reworked molluscs and wood fragments to constrain when the ice sheet retreated behind its present-day extent. The 10Be ages are scattered ranging from ca. 92.7 to 6.8ka, whereas the in situ 14C ages range from ca. 14.2 to 6.7ka. Almost half of the apparent 10Be ages predate the Last Glacial Maximum and up to 89% are to some degree affected by nuclide inheritance. Based on the few reliable 10Be ages, the in situ 14C ages and existing radiocarbon ages from Inglefield Land, we find that the deglaciation along the coast commenced at ca. 8.6-8.3kacalBP in the western part and ca. 7.9ka in the central part, following the opening of Nares Strait and arrival of warm waters. The ice margin reached its present-day position at ca. 8.2ka at the Humboldt Glacier and ca. 6.7ka in the central part of Inglefield Land. Radiocarbon ages of reworked molluscs and wood fragments show that the ice margin was behind its present-day extent from ca. 5.8 to 0.5kacalBP. After 0.5kacalBP, the ice advanced towards its Little Ice Age position. Our results emphasize that the slowly eroding and possibly cold-based ice in north Greenland makes it difficult to constrain the deglaciation history based on 10Be ages alone unless they are paired with in situ 14C ages. Further, combining our findings with those of recently published studies reveals distinct differences between deglaciation patterns of northwest and north Greenland. Deglaciation of the land areas in northwest Greenland occurred earlier than in north Greenland, and periods of restricted ice extent were longer, spanning the Middle and Late Holocene. Overall, this highlights past ice sheet sensitivity to Holocene climate changes in an area where little information was available just a few years ago. © 2020 EDP Sciences. All rights reserved.
语种	英语
scopus关键词	climate change; dating method; deglaciation; glacial history; global warming; Holocene; ice margin; in situ measurement; Last Glacial Maximum; Little Ice Age; paleoclimate; radiocarbon dating; Arctic; Greenland; Greenland Ice Sheet; Humboldt Glacier; Inglefield Land; Nares Strait; Mollusca
来源期刊	Climate of the Past
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/146657
作者单位	Department of Geoscience, Aarhus University, Høegh Guldbergs Gade 2, Aarhus C, 8000, Denmark; Globe Institute, University of Copenhagen, Øster Voldgade 5-7, Copenhagen K, 1350, Denmark; Department of Physics, Institute for Particle Physics and Astrophysics, Eth Zürich, Otto-Stern-Weg 5, Zürich, 8093, Switzerland; Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, Aarhus C, 8000, Denmark
推荐引用方式 GB/T 7714	Sofie Søndergaard A.,Krog Larsen N.,Steinemann O.,et al. Glacial history of Inglefield Land; north Greenland from combined in situ 10Be and 14C exposure dating[J],2020,16(5).
APA	Sofie Søndergaard A..,Krog Larsen N..,Steinemann O..,Olsen J..,Funder S..,...&Henrik Kjær K..(2020).Glacial history of Inglefield Land; north Greenland from combined in situ 10Be and 14C exposure dating.Climate of the Past,16(5).
MLA	Sofie Søndergaard A.,et al."Glacial history of Inglefield Land; north Greenland from combined in situ 10Be and 14C exposure dating".Climate of the Past 16.5(2020).