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Śliwińska KK, Thomsen E, Schouten S, Schoon PL, Heilmann-Clausen C. Climate- and gateway-driven cooling of Late Eocene to earliest Oligocene sea surface temperatures in the North Sea Basin. Sci Rep 2019; 9:4458. [PMID: 30872690 PMCID: PMC6418185 DOI: 10.1038/s41598-019-41013-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 02/27/2019] [Indexed: 11/09/2022] Open
Abstract
During the late Eocene, the Earth’s climate experienced several transient temperature fluctuations including the Vonhof cooling event (C16n.1n; ~35.8 Ma) hitherto known mainly from the southern oceans. Here we reconstruct sea-surface temperatures (SST) and provide δ18O and δ13C foraminiferal records for the late Eocene and earliest Oligocene in the North Sea Basin. Our data reveal two main perturbations: (1), an abrupt brief cooling of ~4.5 °C dated to ~35.8 Ma and synchronous with the Vonhof cooling, which thus may be a global event, and (2) a gradual nearly 10 °C temperature fall starting at 36.1 Ma and culminating near the Eocene-Oligocene transition at ~33.9 Ma. The late Priabonian temperature trend in the North Sea shows some resemblance IODP Site U1404 from the North Atlantic, offshore Newfoundland; and is in contrast to the more abrupt change observed in the deep-sea δ18O records from the southern oceans. The cooling in the North Sea is large compared to the pattern seen in the North Atlantic record. This difference may be influenced by a late Eocene closure of the warm gateways connecting the North Sea with the Atlantic and Tethys oceans.
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Affiliation(s)
- Kasia K Śliwińska
- GEUS Geological Survey of Denmark and Greenland, Department of Stratigraphy, Øster Voldgade 10, 1350, Copenhagen K, Denmark.
| | - Erik Thomsen
- Aarhus University, Department of Geoscience, Høegh-Guldbergs Gade 2, 8000, Århus C, Denmark
| | - Stefan Schouten
- NIOZ Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, Utrecht University, Texel, The Netherlands.,Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Utrecht, The Netherlands
| | - Petra L Schoon
- NIOZ Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, Utrecht University, Texel, The Netherlands
| | - Claus Heilmann-Clausen
- Aarhus University, Department of Geoscience, Høegh-Guldbergs Gade 2, 8000, Århus C, Denmark
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Galeotti S, DeConto R, Naish T, Stocchi P, Florindo F, Pagani M, Barrett P, Bohaty SM, Lanci L, Pollard D, Sandroni S, Talarico FM, Zachos JC. Antarctic Ice Sheet variability across the Eocene-Oligocene boundary climate transition. Science 2016; 352:76-80. [PMID: 27034370 DOI: 10.1126/science.aab0669] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2015] [Accepted: 02/24/2016] [Indexed: 11/02/2022]
Abstract
About 34 million years ago, Earth's climate cooled and an ice sheet formed on Antarctica as atmospheric carbon dioxide (CO2) fell below ~750 parts per million (ppm). Sedimentary cycles from a drill core in the western Ross Sea provide direct evidence of orbitally controlled glacial cycles between 34 million and 31 million years ago. Initially, under atmospheric CO2 levels of ≥600 ppm, a smaller Antarctic Ice Sheet (AIS), restricted to the terrestrial continent, was highly responsive to local insolation forcing. A more stable, continental-scale ice sheet calving at the coastline did not form until ~32.8 million years ago, coincident with the earliest time that atmospheric CO2 levels fell below ~600 ppm. Our results provide insight into the potential of the AIS for threshold behavior and have implications for its sensitivity to atmospheric CO2 concentrations above present-day levels.
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Affiliation(s)
- Simone Galeotti
- Dipartimento di Scienze Pure e Applicate, Università degli Studi di Urbino "Carlo Bo," 61029 Urbino, Italy.
| | - Robert DeConto
- Department of Geosciences, University of Massachusetts, Amherst, MA, USA
| | - Timothy Naish
- Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand. GNS Science, P.O. Box 30368, Lower Hutt, New Zealand
| | - Paolo Stocchi
- NIOZ Royal Netherlands Institute for Sea Research, Department of Coastal Systems, and Utrecht University, 1790 AB Den Burg, Texel, Netherlands
| | - Fabio Florindo
- Istituto Nazionale di Geofisica e Vulcanologia, 00143 Rome, Italy
| | - Mark Pagani
- Department of Geology and Geophysics, Yale University, New Haven, CT, USA
| | - Peter Barrett
- Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand
| | - Steven M Bohaty
- Ocean and Earth Science, University of Southampton, National Oceanography Centre, Southampton SO14 3ZH, UK
| | - Luca Lanci
- Dipartimento di Scienze Pure e Applicate, Università degli Studi di Urbino "Carlo Bo," 61029 Urbino, Italy
| | - David Pollard
- Earth System Science Center, Pennsylvania State University, State College, PA, USA
| | - Sonia Sandroni
- Museo Nazionale dell'Antartide, Università degli Studi di Siena, 53100 Siena, Italy
| | - Franco M Talarico
- Museo Nazionale dell'Antartide, Università degli Studi di Siena, 53100 Siena, Italy. Dipartimento di Scienze Fisiche, della Terra e dell'Ambiente, Università degli Studi di Siena, 53100 Siena, Italy
| | - James C Zachos
- Earth Sciences Department, University of California, Santa Cruz, CA 95064, USA
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