气候变化领域集成服务门户(CCPortal): Impact of abrupt sea ice loss on Greenland water isotopes during the last glacial period

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DOI	10.1073/pnas.1807261116
	Impact of abrupt sea ice loss on Greenland water isotopes during the last glacial period
	Sime L.C.; Hopcroft P.O.; Rhodes R.H.
发表日期	2019
ISSN	0027-8424
起始页码	4099
结束页码	4104
卷号	116 期号:10
英文摘要	Greenland ice cores provide excellent evidence of past abrupt climate changes. However, there is no universally accepted theory of how and why these Dansgaard–Oeschger (DO) events occur. Several mechanisms have been proposed to explain DO events, including sea ice, ice shelf buildup, ice sheets, atmospheric circulation, and meltwater changes. DO event temperature reconstructions depend on the stable water isotope (δ 18 O) and nitrogen isotope measurements from Greenland ice cores: interpretation of these measurements holds the key to understanding the nature of DO events. Here, we demonstrate the primary importance of sea ice as a control on Greenland ice core δ 18 O: 95% of the variability in δ 18 O in southern Greenland is explained by DO event sea ice changes. Our suite of DO events, simulated using a general circulation model, accurately captures the amplitude of δ 18 O enrichment during the abrupt DO event onsets. Simulated geographical variability is broadly consistent with available ice core evidence. We find an hitherto unknown sensitivity of the δ 18 O paleothermometer to the magnitude of DO event temperature increase: the change in δ 18 O per Kelvin temperature increase reduces with DO event amplitude. We show that this effect is controlled by precipitation seasonality. © 2019 National Academy of Sciences. All Rights Reserved.
英文关键词	Abrupt warmings; Arctic; climate change; paleoclimate; sea ice
语种	英语
scopus关键词	oxygen 18; Article; controlled study; glacial period; Greenland; mathematical model; measurement accuracy; precipitation; priority journal; sea ice; seasonal variation; temperature
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/160425
作者单位	Sime, L.C., Ice Dynamics and Palaeoclimate, British Antarctic Survey, Cambridge, CB3 0ET, United Kingdom; Hopcroft, P.O., School of Geography, Earth and Environmental Sciences, University of Birmingham, Edgbaston, B15 2TT, United Kingdom; Rhodes, R.H., Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, United Kingdom, Department of Geography and Environmental Sciences, Northumbria University, Newcastle upon Tyne, NE1 8ST, United Kingdom
推荐引用方式 GB/T 7714	Sime L.C.,Hopcroft P.O.,Rhodes R.H.. Impact of abrupt sea ice loss on Greenland water isotopes during the last glacial period[J],2019,116(10).
APA	Sime L.C.,Hopcroft P.O.,&Rhodes R.H..(2019).Impact of abrupt sea ice loss on Greenland water isotopes during the last glacial period.Proceedings of the National Academy of Sciences of the United States of America,116(10).
MLA	Sime L.C.,et al."Impact of abrupt sea ice loss on Greenland water isotopes during the last glacial period".Proceedings of the National Academy of Sciences of the United States of America 116.10(2019).