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Rapid northern hemisphere ice sheet melting during the penultimate deglaciation. Nat Commun 2022; 13:3819. [PMID: 35780147 PMCID: PMC9250507 DOI: 10.1038/s41467-022-31619-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 06/27/2022] [Indexed: 11/17/2022] Open
Abstract
The rate and consequences of future high latitude ice sheet retreat remain a major concern given ongoing anthropogenic warming. Here, new precisely dated stalagmite data from NW Iberia provide the first direct, high-resolution records of periods of rapid melting of Northern Hemisphere ice sheets during the penultimate deglaciation. These records reveal the penultimate deglaciation initiated with rapid century-scale meltwater pulses which subsequently trigger abrupt coolings of air temperature in NW Iberia consistent with freshwater-induced AMOC slowdowns. The first of these AMOC slowdowns, 600-year duration, was shorter than Heinrich 1 of the last deglaciation. Although similar insolation forcing initiated the last two deglaciations, the more rapid and sustained rate of freshening in the eastern North Atlantic penultimate deglaciation likely reflects a larger volume of ice stored in the marine-based Eurasian Ice sheet during the penultimate glacial in contrast to the land-based ice sheet on North America as during the last glacial. Stalagmites from NW Iberia record the rapid demise of large ice sheets during the penultimate deglaciation, and reveal decadal-scale feedbacks between warming and ice melting.
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Cheng H, Edwards RL, Southon J, Matsumoto K, Feinberg JM, Sinha A, Zhou W, Li H, Li X, Xu Y, Chen S, Tan M, Wang Q, Wang Y, Ning Y. Atmospheric
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C changes during the last glacial period from Hulu Cave. Science 2018; 362:1293-1297. [DOI: 10.1126/science.aau0747] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 11/02/2018] [Indexed: 11/02/2022]
Affiliation(s)
- Hai Cheng
- Institute of Global Environmental Change, Xi’an Jiaotong University, China
- Department of Earth Sciences, University of Minnesota, Minneapolis, MN, USA
| | | | - John Southon
- Department of Earth System Science, University of California, Irvine, CA, USA
| | - Katsumi Matsumoto
- Department of Earth Sciences, University of Minnesota, Minneapolis, MN, USA
| | - Joshua M. Feinberg
- Department of Earth Sciences, University of Minnesota, Minneapolis, MN, USA
- Institute for Rock Magnetism, University of Minnesota, Minneapolis, MN, USA
| | - Ashish Sinha
- Department of Earth Science, California State University Dominguez Hills, Carson, CA, USA
| | - Weijian Zhou
- Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, China
| | - Hanying Li
- Institute of Global Environmental Change, Xi’an Jiaotong University, China
| | - Xianglei Li
- Institute of Global Environmental Change, Xi’an Jiaotong University, China
| | - Yao Xu
- Institute of Global Environmental Change, Xi’an Jiaotong University, China
| | - Shitao Chen
- College of Geography Science, Nanjing Normal University, Nanjing, China
| | - Ming Tan
- Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, China
| | - Quan Wang
- College of Geography Science, Nanjing Normal University, Nanjing, China
| | - Yongjin Wang
- College of Geography Science, Nanjing Normal University, Nanjing, China
| | - Youfeng Ning
- Institute of Global Environmental Change, Xi’an Jiaotong University, China
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Hu R, Piotrowski AM. Neodymium isotope evidence for glacial-interglacial variability of deepwater transit time in the Pacific Ocean. Nat Commun 2018; 9:4709. [PMID: 30413704 PMCID: PMC6226442 DOI: 10.1038/s41467-018-07079-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 10/10/2018] [Indexed: 11/25/2022] Open
Abstract
There is evidence for greater carbon storage in the glacial deep Pacific, but it is uncertain whether it was caused by changes in ventilation, circulation, and biological productivity. The spatial εNd evolution in the deep Pacific provides information on the deepwater transit time. Seven new foraminiferal εNd records are presented to systematically constrain glacial to interglacial changes in deep Pacific overturning and two different εNd evolution regimes occur spatially in the Pacific with reduced meridional εNd gradients in glacials, suggesting a faster deep Pacific overturning circulation. This implies that greater glacial carbon storage due to sluggish circulation, that is believed to have occurred in the deep Atlantic, did not operate in a similar manner in the Pacific Ocean. Other mechanisms such as increased biological pump efficiency and poor high latitude air-sea exchange could be responsible for increased carbon storage in the glacial Pacific. The response of deep Pacific overturning to glacial-interglacial climate change is still debated. Here the authors show a generally faster deep Pacific overturning operated in recent glacial periods based on a novel application of Nd isotopes recorded in foraminifera.
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Affiliation(s)
- Rong Hu
- School of Geography and Ocean Science, Nanjing University, 210023, Nanjing, China. .,Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, UK.
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Magill CR, Ausín B, Wenk P, McIntyre C, Skinner L, Martínez-García A, Hodell DA, Haug GH, Kenney W, Eglinton TI. Transient hydrodynamic effects influence organic carbon signatures in marine sediments. Nat Commun 2018; 9:4690. [PMID: 30410023 PMCID: PMC6224525 DOI: 10.1038/s41467-018-06973-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 09/19/2018] [Indexed: 11/09/2022] Open
Abstract
Ocean dynamics served an important role during past dramatic climate changes via impacts on deep-ocean carbon storage. Such changes are recorded in sedimentary proxies of hydrographic change on continental margins, which lie at the ocean-atmosphere-earth interface. However, interpretations of these records are challenging, given complex interplays among processes delivering particulate material to and from ocean margins. Here we report radiocarbon (14C) signatures measured for organic carbon in differing grain-size sediment fractions and foraminifera in a sediment core retrieved from the southwest Iberian margin, spanning the last ~25,000 yr. Variable differences of 0-5000 yr in radiocarbon age are apparent between organic carbon in differing grain-sizes and foraminifera of the same sediment layer. The magnitude of 14C differences co-varies with key paleoceanographic indices (e.g., proximal bottom-current density gradients), which we interpret as evidence of Atlantic-Mediterranean seawater exchange influencing grain-size specific carbon accumulation and translocation. These findings underscore an important link between regional hydrodynamics and interpretations of down-core sedimentary proxies.
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Affiliation(s)
- Clayton R Magill
- Geological Institute, ETH Zürich, Zürich, 8092, Switzerland.
- Lyell Centre, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom.
| | - Blanca Ausín
- Geological Institute, ETH Zürich, Zürich, 8092, Switzerland
| | - Pascal Wenk
- Geological Institute, ETH Zürich, Zürich, 8092, Switzerland
| | - Cameron McIntyre
- Geological Institute, ETH Zürich, Zürich, 8092, Switzerland
- Laboratory for Ion Beam Physics, ETH Zürich, Zürich, 8093, Switzerland
- Scottish Universities Environmental Research Centre (SUERC), East Kilbride, G750QF, United Kingdom
| | - Luke Skinner
- Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, United Kingdom
| | - Alfredo Martínez-García
- Geological Institute, ETH Zürich, Zürich, 8092, Switzerland
- Max Planck Institute for Chemistry, D-55128, Mainz, Germany
| | - David A Hodell
- Department of Earth Sciences, University of Cambridge, Cambridge, CB2 3EQ, United Kingdom
| | - Gerald H Haug
- Geological Institute, ETH Zürich, Zürich, 8092, Switzerland
- Max Planck Institute for Chemistry, D-55128, Mainz, Germany
| | - William Kenney
- Land Use and Environmental Change Institute, University of Florida, Gainesville, FL, 32611, United States
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Mleneck-Vautravers MJ. Quantitative planktonic foraminifers taphonomy and palaeoceanographic implications over the last 1 My from IODP Sites U1436 and U1437. ACTA ACUST UNITED AC 2018. [DOI: 10.1080/23312041.2018.1447263] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Affiliation(s)
- Maryline J. Mleneck-Vautravers
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK
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Skinner LC, Primeau F, Freeman E, de la Fuente M, Goodwin PA, Gottschalk J, Huang E, McCave IN, Noble TL, Scrivner AE. Radiocarbon constraints on the glacial ocean circulation and its impact on atmospheric CO 2. Nat Commun 2017; 8:16010. [PMID: 28703126 PMCID: PMC5511348 DOI: 10.1038/ncomms16010] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Accepted: 05/22/2017] [Indexed: 11/15/2022] Open
Abstract
While the ocean’s large-scale overturning circulation is thought to have been significantly different under the climatic conditions of the Last Glacial Maximum (LGM), the exact nature of the glacial circulation and its implications for global carbon cycling continue to be debated. Here we use a global array of ocean–atmosphere radiocarbon disequilibrium estimates to demonstrate a ∼689±53 14C-yr increase in the average residence time of carbon in the deep ocean at the LGM. A predominantly southern-sourced abyssal overturning limb that was more isolated from its shallower northern counterparts is interpreted to have extended from the Southern Ocean, producing a widespread radiocarbon age maximum at mid-depths and depriving the deep ocean of a fast escape route for accumulating respired carbon. While the exact magnitude of the resulting carbon cycle impacts remains to be confirmed, the radiocarbon data suggest an increase in the efficiency of the biological carbon pump that could have accounted for as much as half of the glacial–interglacial CO2 change. Establishing the efficiency of the biological carbon pump is needed to constrain the impact of ocean circulation on the carbon cycle. Here, the authors compile a global array of ocean–atmosphere radiocarbon disequilibrium estimates and evaluate the strength of the carbon pump over the last glacial maximum.
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Affiliation(s)
- L C Skinner
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - F Primeau
- Department of Earth System Science, University of California, Irvine, California 92697-3100, USA
| | - E Freeman
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - M de la Fuente
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - P A Goodwin
- National Oceanography Centre, University of Southampton, Southampton SO14 3ZH, UK
| | - J Gottschalk
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK.,Oeschger Center for Climate Change Research Institute for Geology University of Bern Baltzerstr. 1-3, 3012 Bern, Switzerland
| | - E Huang
- MARUM-Center for Marine Environmental Sciences and Faculty of Geosciences, University of Bremen, Bremen D-28359, Germany
| | - I N McCave
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
| | - T L Noble
- Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania 7001, Australia
| | - A E Scrivner
- Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK
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