气候变化领域集成服务门户(CCPortal): Glacier expansion on Baffin Island during early Holocene cold reversals

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DOI	10.1016/j.quascirev.2020.106419
	Glacier expansion on Baffin Island during early Holocene cold reversals
	Crump S.E.; Young N.E.; Miller G.H.; Pendleton S.L.; Tulenko J.P.; Anderson R.S.; Briner J.P.
发表日期	2020
ISSN	0277-3791
卷号	241
英文摘要	The North Atlantic was a key locus for circulation-driven abrupt climate change in the past and could play a similar role in the future. Abrupt cold reversals, including the 8.2 ka event, punctuated the otherwise warm early Holocene in the North Atlantic region and serve as useful paleo examples of rapid climate change. In this work, we assess the cryospheric response to early Holocene climate history on Baffin Island, Arctic Canada, using cosmogenic radionuclide dating of moraines. We present 39 new 10Be ages from four sets of multi-crested early Holocene moraines deposited by cirque glaciers and ice cap outlet glaciers, as well as erratic boulders along adjacent fiords to constrain the timing of regional deglaciation. The age of one moraine is additionally constrained by in situ 14C measurements, which confirm 10Be inheritance in some samples. All four moraines were deposited between ∼9.2 and 8.0 ka, and their average ages coincide with abrupt coolings at 9.3 and 8.2 ka that are recorded in Greenland ice cores. Freshwater delivery to the North Atlantic that reduced the flux of warm Atlantic water into Baffin Bay may explain brief intervals of glacier advance, although moraine formation cannot be definitively tied to centennial-scale cold reversals. We thus explore other possible contributing factors, including ice dynamics related to retreat of Laurentide Ice Sheet outlet glaciers. Using a numerical glacier model, we show that the debuttressing effect of trunk valley deglaciation may have contributed to these moraine-building events. These new age constraints and process insights highlight the complex behavior of the cryosphere during regional deglaciation and suggest that multiple abrupt cold reversals—as well as deglacial ice dynamics—likely played a role in early Holocene moraine formation on Baffin Island. © 2020 Elsevier Ltd
英文关键词	Abrupt climate change; Arctic; Cosmogenic isotopes; Glacial geomorphology; Glaciology; Holocene; Paleoclimatology
语种	英语
scopus关键词	Ice; Abrupt climate change; Atlantic water; Contributing factor; Cosmogenic radionuclides; Early Holocene; Greenland ice cores; Laurentide ice sheets; Rapid climate change; Climate change; climate change; cosmogenic radionuclide; cryosphere; deglaciation; Holocene; ice cap; ice core; Laurentide Ice Sheet; moraine; Arctic; Atlantic Ocean; Atlantic Ocean (North); Baffin Bay; Baffin Island; Canada; Greenland; Nunavut
来源期刊	Quaternary Science Reviews
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/151400
作者单位	INSTAAR and Geological Sciences, University of Colorado Boulder, 4001 Discovery Drive, Boulder, CO, United States; Lamont-Doherty Earth Observatory, Columbia University, 61 Rte 9W, Palisades, NY, United States; Woods Hole Oceanographic Institution, 86 Water St., Woods HoleMA, United States; Department of Geology, University at Buffalo, 126 Cooke Hall, Buffalo, NY, United States
推荐引用方式 GB/T 7714	Crump S.E.,Young N.E.,Miller G.H.,et al. Glacier expansion on Baffin Island during early Holocene cold reversals[J],2020,241.
APA	Crump S.E..,Young N.E..,Miller G.H..,Pendleton S.L..,Tulenko J.P..,...&Briner J.P..(2020).Glacier expansion on Baffin Island during early Holocene cold reversals.Quaternary Science Reviews,241.
MLA	Crump S.E.,et al."Glacier expansion on Baffin Island during early Holocene cold reversals".Quaternary Science Reviews 241(2020).