气候变化领域集成服务门户(CCPortal): Antarctic ice-sheet sensitivity to obliquity forcing enhanced through ocean connections

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DOI	10.1038/s41561-018-0284-4
	Antarctic ice-sheet sensitivity to obliquity forcing enhanced through ocean connections
	Levy R.H.; Meyers S.R.; Naish T.R.; Golledge N.R.; McKay R.M.; Crampton J.S.; DeConto R.M.; De Santis L.; Florindo F.; Gasson E.G.W.; Harwood D.M.; Luyendyk B.P.; Powell R.D.; Clowes C.; Kulhanek D.K.
发表日期	2019
ISSN	17520894
卷号	12 期号:2
英文摘要	Deep sea geological records indicate that Antarctic ice-sheet growth and decay is strongly influenced by the Earth’s astronomical variations (known as Milankovitch cycles), and that the frequency of the glacial–interglacial cycles changes through time. Here we examine the emergence of a strong obliquity (axial tilt) control on Antarctic ice-sheet evolution during the Miocene by correlating the Antarctic margin geological records from 34 to 5 million years ago with a measure of obliquity sensitivity that compares the variance in deep sea sediment core oxygen-isotope data at obliquity timescales with variance of the calculated obliquity forcing. Our analysis reveals distinct phases of ice-sheet evolution and suggests the sensitivity to obliquity forcing increases when ice-sheet margins extend into marine environments. We propose that this occurs because obliquity-driven changes in the meridional temperature gradient affect the position and strength of the circum-Antarctic easterly flow and enhance (or reduce) ocean heat transport across the Antarctic continental margin. The influence of obliquity-driven changes in ocean dynamics is amplified when marine ice sheets are extensive, and sea ice is limited. Our reconstruction of the Antarctic ice-sheet history suggests that if sea-ice cover decreases in the coming decades, ocean-driven melting at the ice-sheet margin will be amplified. © 2019, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	core analysis; deep-sea sediment; easterly wave; glacial-interglacial cycle; meridional circulation; Milankovitch cycle; obliquity; oxygen isotope; reconstruction; sensitivity analysis; temperature gradient; Antarctic Ice Sheet; Antarctica
来源期刊	Nature Geoscience
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/124722
作者单位	GNS Science, Lower Hutt, New Zealand; Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand; Department of Geoscience, University of Wisconsin—Madison, Madison, WI, United States; School of Geography, Environment and Earth Science, Victoria University of Wellington, Wellington, New Zealand; Department of Geosciences, University of Massachusetts, Amherst, MA, United States; Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS), Sgonico, Trieste, Italy; Istituto Nazionale di Geofisica e Vulcanologia (INGV), Roma, Italy; School of Geographical Sciences, University of Bristol, Bristol, United Kingdom; Earth & Atmospheric Sciences, University of Nebraska, Lincoln, Lincoln, NE, United States; Earth Science Department, University of California, Santa Barbara, Santa Barbara, CA, United States; Department of Geology and Environmental Geosciences, Northern Illinois University, DeKalb, IL, United States; International Ocean Discovery Program, Texas A&M University, Colle...
推荐引用方式 GB/T 7714	Levy R.H.,Meyers S.R.,Naish T.R.,et al. Antarctic ice-sheet sensitivity to obliquity forcing enhanced through ocean connections[J],2019,12(2).
APA	Levy R.H..,Meyers S.R..,Naish T.R..,Golledge N.R..,McKay R.M..,...&Kulhanek D.K..(2019).Antarctic ice-sheet sensitivity to obliquity forcing enhanced through ocean connections.Nature Geoscience,12(2).
MLA	Levy R.H.,et al."Antarctic ice-sheet sensitivity to obliquity forcing enhanced through ocean connections".Nature Geoscience 12.2(2019).