气候变化领域集成服务门户(CCPortal): Deglaciation of the Greenland and Laurentide ice sheets interrupted by glacier advance during abrupt coolings

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DOI	10.1016/j.quascirev.2019.106091
	Deglaciation of the Greenland and Laurentide ice sheets interrupted by glacier advance during abrupt coolings
	Young N.E.; Briner J.P.; Miller G.H.; Lesnek A.J.; Crump S.E.; Thomas E.K.; Pendleton S.L.; Cuzzone J.; Lamp J.; Zimmerman S.; Caffee M.; Schaefer J.M.
发表日期	2020
ISSN	0277-3791
卷号	229
英文摘要	Understanding patterns of ice-sheet deglaciation is key for predicting the rate of future ice-sheet melt, yet the processes underlying deglaciation remain elusive. The early Holocene (11.7 ka to 8.2 ka; Greenlandian Stage) represents the most recent period when the Laurentide and Greenland ice sheets underwent large-scale recession. Moreover, this ice-sheet recession occurred under the backdrop of regional temperatures that were similar to or warmer than today, and comparable to those projected for the upcoming centuries. Reconstructing Laurentide and Greenland ice sheet behavior during the early Holocene, and elucidating the mechanisms dictating this behavior may serve as a partial analog for future Greenland ice-sheet change in a warming world. Here, we present 123 new 10Be surface exposure ages from two sites on Baffin Island and southwestern Greenland that constrain the behavior of the Laurentide and Greenland ice sheets, and an independent alpine glacier during the early Holocene. On Baffin Island, we focus on a unique area where moraines deposited by the Laurentide Ice Sheet rest directly adjacent to moraines deposited by an independent alpine glacier. Sixty-one 10Be ages reveal that advances and/or stillstands of the Laurentide Ice Sheet and an alpine glacier occurred in unison around 11.8 ka, 10.3 ka, and 9.2 ka. Sixty-two 10Be ages from southwestern Greenland indicate that the Greenland Ice Sheet margin experienced re-advances or stillstands around 11.6 ka, 10.4 ka, 9.1 ka, 8.1 ka, and 7.3 ka. Our results reveal that ice sheets respond to climate perturbations on the same centennial timescale as small alpine glaciers. We hypothesize that during the warming climate of the early Holocene, freshening of the North Atlantic Ocean induced by ice-sheet melt resulted in regional cooling and brief periods of ice-sheet stabilization superimposed on net glacier recession. These observations point to a negative feedback mechanism inherent to melting ice sheets in the Baffin Bay region that slows ice-sheet recession during intervals of otherwise rapid deglaciation. © 2019 Elsevier Ltd
语种	英语
scopus关键词	Glaciers; Glacier recession; Greenland Ice Sheet; Laurentide ice sheets; Negative feedback mechanism; North Atlantic Ocean; Regional cooling; Surface exposure age; Warming climate; Ice; cooling; feedback mechanism; glacier advance; Holocene; Laurentide Ice Sheet; moraine; valley glacier; Arctic; Atlantic Ocean; Atlantic Ocean (North); Baffin Bay; Baffin Island; Canada; Greenland; Greenland Ice Sheet; 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/151625
作者单位	Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, United States; Department of Geology, University at Buffalo, Buffalo, NY, United States; INSTAAR and Department of Geological Sciences, University of Colorado Boulder, Boulder, CO, United States; Department of Earth System Science, University of California Irvine, Irvine, CA, United States; Lawrence Livermore National Laboratory, Center for Accelerator Mass Spectrometry, Livermore, CA, United States; Department of Physics, PRIME Lab, Purdue University, West Lafayette, IN, United States; Department of Earth, Atmospheric, and Planetary Science, Purdue University, West Lafayette, IN, United States
推荐引用方式 GB/T 7714	Young N.E.,Briner J.P.,Miller G.H.,et al. Deglaciation of the Greenland and Laurentide ice sheets interrupted by glacier advance during abrupt coolings[J],2020,229.
APA	Young N.E..,Briner J.P..,Miller G.H..,Lesnek A.J..,Crump S.E..,...&Schaefer J.M..(2020).Deglaciation of the Greenland and Laurentide ice sheets interrupted by glacier advance during abrupt coolings.Quaternary Science Reviews,229.
MLA	Young N.E.,et al."Deglaciation of the Greenland and Laurentide ice sheets interrupted by glacier advance during abrupt coolings".Quaternary Science Reviews 229(2020).