气候变化领域集成服务门户(CCPortal): Vertical decoupling in Late Ordovician anoxia due to reorganization of ocean circulation

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DOI	10.1038/s41561-021-00843-9
	Vertical decoupling in Late Ordovician anoxia due to reorganization of ocean circulation
	Pohl A.; Lu Z.; Lu W.; Stockey R.G.; Elrick M.; Li M.; Desrochers A.; Shen Y.; He R.; Finnegan S.; Ridgwell A.
发表日期	2021
ISSN	1752-0894
卷号	14 期号:11
英文摘要	Geochemical redox proxies indicate that seafloor anoxia occurred during the latest Ordovician glacial maximum, coincident with the second pulse of the Late Ordovician mass extinction. However, expanded anoxia in a glacial climate strikingly contrasts with the warming-associated Mesozoic anoxic events and raises questions as to both the causal mechanism of ocean deoxygenation and its relationship with extinction. Here we firstly report iodine-to-calcium ratio (I/Ca) data that document increased upper-ocean oxygenation despite the concurrent expansion of seafloor anoxia. We then resolve these apparently conflicting observations as well as their relationship to global climate by means of a series of Earth system model simulations. Applying available Late Ordovician (Hirnantian) sea-surface temperature estimates from oxygen isotope studies as constraints, alongside our I/Ca data, leads us to identify a scenario in which Hirnantian glacial conditions permit both the spread of seafloor anoxia and increased upper-ocean oxygenation. Our simulated mechanism of a reorganization of global ocean circulation, with reduced importance of northern-sourced waters and a poorer ventilated and deoxygenated deep ocean has parallels with Pleistocene state transitions in Atlantic meridional overturning (despite a very different continental configuration) and suggests that no simple and predictable relationship between past climate state and oxygenation may exist. © 2021, The Author(s), under exclusive licence to Springer Nature Limited.
语种	英语
scopus关键词	anoxia; circulation; global climate; global ocean; Hirnantian; isotope; Atlantic Ocean; Trachinotus falcatus
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/250840
作者单位	Department of Earth and Planetary Sciences, University of California, Riverside, CA, United States; Biogéosciences, UMR 6282, UBFC/CNRS, Université Bourgogne Franche-Comté, Dijon, France; Department of Earth Sciences, Syracuse University, Syracuse, NY, United States; Department of Geological Sciences, Stanford University, Stanford, CA, United States; Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM, Mexico; School of Earth and Space Sciences, University of Science and Technology of China, Hefei, China; Earth and Environmental Sciences, University of Ottawa, Ottawa, ON, Canada; Department of Integrative Biology, University of California, Berkeley, Berkeley, CA, United States
推荐引用方式 GB/T 7714	Pohl A.,Lu Z.,Lu W.,et al. Vertical decoupling in Late Ordovician anoxia due to reorganization of ocean circulation[J],2021,14(11).
APA	Pohl A..,Lu Z..,Lu W..,Stockey R.G..,Elrick M..,...&Ridgwell A..(2021).Vertical decoupling in Late Ordovician anoxia due to reorganization of ocean circulation.Nature Geoscience,14(11).
MLA	Pohl A.,et al."Vertical decoupling in Late Ordovician anoxia due to reorganization of ocean circulation".Nature Geoscience 14.11(2021).