气候变化领域集成服务门户(CCPortal): Coupled atmosphere-ice-ocean dynamics in Dansgaard-Oeschger events

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DOI	10.1016/j.quascirev.2018.10.031
	Coupled atmosphere-ice-ocean dynamics in Dansgaard-Oeschger events
	Li C.; Born A.
发表日期	2019
ISSN	0277-3791
起始页码	1
结束页码	20
卷号	203
英文摘要	The Dansgaard-Oeschger events of the last ice age are among the best studied abrupt climate changes, yet a comprehensive explanation is still lacking. They are most pronounced in the North Atlantic, where they manifest as large temperature swings, on timescales of decades or shorter, between persistent cold (stadial) and warm (interstadial) conditions. This review examines evidence that Dansgaard-Oeschger events are an unforced or “spontaneous” oscillation of the coupled atmosphere-ice-ocean system comprising the North Atlantic, Nordic Seas and Arctic, collectively termed the Northern Seas. Insights from reanalysis data, climate model simulations, and idealized box model experiments point to the subpolar gyre as a key coupling region where vigorous wind systems encounter the southernmost extension of sea ice and the most variable currents of the North Atlantic, with connections to the deep ocean via convection. We argue that, under special conditions, these components can interact to produce Dansgaard-Oeschger events. Finding the sweet spot is a matter of understanding when the subpolar region enters a feedback loop whereby changes in wind forcing, sea ice cover, and ocean circulation amplify and sustain perturbations towards cold (ice-covered) or warm (ice-free) conditions. The resulting Dansgaard-Oeschger-like variability is seen in a handful of model simulations, including some “ugly duckling” pre-industrial simulations: these may be judged as undesirable at the outset, but ultimately show value in suggesting that current models include the necessary physics to produce abrupt climate transitions, but exhibit incorrect sensitivity to the boundary conditions. Still, glacial climates are hypothesized to favour larger, more persistent transitions due to differences in large-scale wind patterns. Simplified models and idealized experimental setups may provide a means to constrain how the critical processes act, both in isolation and in combination, to destabilize the subpolar North Atlantic. © 2018 The Authors
英文关键词	Abrupt climate change; Climate dynamics; Dansgaard-Oeschger events; Jet stream; North Atlantic; Pleistocene; Subpolar gyre
语种	英语
scopus关键词	Climate models; Glacial geology; Ocean currents; Sea ice; Abrupt climate change; Climate dynamics; Dansgaard-oeschger events; Jet streams; North Atlantic; Pleistocene; Subpolar gyres; Climate change; atmosphere-ice-ocean system; climate variation; convection; Dansgaard-Oeschger cycle; gyre; jet stream; oceanic circulation; Pleistocene; polar region; sea ice; wind forcing; Arctic; Arctic Ocean; Atlantic Ocean; Atlantic Ocean (North); Norwegian Sea
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/152081
作者单位	Geophysical Institute, University of Bergen, Bergen, Norway; Bjerknes Centre for Climate Research, Bergen, Norway; Department of Earth Sciences, University of Bergen, Bergen, Norway
推荐引用方式 GB/T 7714	Li C.,Born A.. Coupled atmosphere-ice-ocean dynamics in Dansgaard-Oeschger events[J],2019,203.
APA	Li C.,&Born A..(2019).Coupled atmosphere-ice-ocean dynamics in Dansgaard-Oeschger events.Quaternary Science Reviews,203.
MLA	Li C.,et al."Coupled atmosphere-ice-ocean dynamics in Dansgaard-Oeschger events".Quaternary Science Reviews 203(2019).