Eocene bipolar glaciation associated with global carbon cycle changes.
The transition from the extreme global warmth of the early Eocene 'greenhouse' climate approx55 million years ago to the present glaciated state is one of the most prominent changes in Earth's climatic evolution. It is widely accepted that large ice sheets first appeared on Antarctica...
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Online Access: | http://eprints.esc.cam.ac.uk/1850/ http://eprints.esc.cam.ac.uk/1850/1/Eocene_bipolar_-_Tripati.pdf https://doi.org/10.1038/nature03874 |
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ftucambridgeesc:oai:eprints.esc.cam.ac.uk:1850 2023-05-15T13:32:21+02:00 Eocene bipolar glaciation associated with global carbon cycle changes. Tripati, A. K. Backman, J. Elderfield, H. Ferretti, P. 2005 application/pdf http://eprints.esc.cam.ac.uk/1850/ http://eprints.esc.cam.ac.uk/1850/1/Eocene_bipolar_-_Tripati.pdf https://doi.org/10.1038/nature03874 en eng http://eprints.esc.cam.ac.uk/1850/1/Eocene_bipolar_-_Tripati.pdf Tripati, A. K. and Backman, J. and Elderfield, H. and Ferretti, P. (2005) Eocene bipolar glaciation associated with global carbon cycle changes. Nature, 437. pp. 339-344. DOI https://doi.org/10.1038/nature03874 <https://doi.org/10.1038/nature03874> 01 - Climate Change and Earth-Ocean Atmosphere Systems Article PeerReviewed 2005 ftucambridgeesc https://doi.org/10.1038/nature03874 2020-08-27T18:09:03Z The transition from the extreme global warmth of the early Eocene 'greenhouse' climate approx55 million years ago to the present glaciated state is one of the most prominent changes in Earth's climatic evolution. It is widely accepted that large ice sheets first appeared on Antarctica approx34 million years ago, coincident with decreasing atmospheric carbon dioxide concentrations and a deepening of the calcite compensation depth in the world's oceans, and that glaciation in the Northern Hemisphere began much later, between 10 and 6 million years ago. Here we present records of sediment and foraminiferal geochemistry covering the greenhouse–icehouse climate transition. We report evidence for synchronous deepening and subsequent oscillations in the calcite compensation depth in the tropical Pacific and South Atlantic oceans from approx42 million years ago, with a permanent deepening 34 million years ago. The most prominent variations in the calcite compensation depth coincide with changes in seawater oxygen isotope ratios of up to 1.5 per mil, suggesting a lowering of global sea level through significant storage of ice in both hemispheres by at least 100 to 125 metres. Variations in benthic carbon isotope ratios of up to approx1.4 per mil occurred at the same time, indicating large changes in carbon cycling. We suggest that the greenhouse–icehouse transition was closely coupled to the evolution of atmospheric carbon dioxide, and that negative carbon cycle feedbacks may have prevented the permanent establishment of large ice sheets earlier than 34 million years ago. Article in Journal/Newspaper Antarc* Antarctica University of Cambridge, Department of Earth Sciences: ESC Publications Pacific Nature 436 7049 341 346 |
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Open Polar |
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University of Cambridge, Department of Earth Sciences: ESC Publications |
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ftucambridgeesc |
language |
English |
topic |
01 - Climate Change and Earth-Ocean Atmosphere Systems |
spellingShingle |
01 - Climate Change and Earth-Ocean Atmosphere Systems Tripati, A. K. Backman, J. Elderfield, H. Ferretti, P. Eocene bipolar glaciation associated with global carbon cycle changes. |
topic_facet |
01 - Climate Change and Earth-Ocean Atmosphere Systems |
description |
The transition from the extreme global warmth of the early Eocene 'greenhouse' climate approx55 million years ago to the present glaciated state is one of the most prominent changes in Earth's climatic evolution. It is widely accepted that large ice sheets first appeared on Antarctica approx34 million years ago, coincident with decreasing atmospheric carbon dioxide concentrations and a deepening of the calcite compensation depth in the world's oceans, and that glaciation in the Northern Hemisphere began much later, between 10 and 6 million years ago. Here we present records of sediment and foraminiferal geochemistry covering the greenhouse–icehouse climate transition. We report evidence for synchronous deepening and subsequent oscillations in the calcite compensation depth in the tropical Pacific and South Atlantic oceans from approx42 million years ago, with a permanent deepening 34 million years ago. The most prominent variations in the calcite compensation depth coincide with changes in seawater oxygen isotope ratios of up to 1.5 per mil, suggesting a lowering of global sea level through significant storage of ice in both hemispheres by at least 100 to 125 metres. Variations in benthic carbon isotope ratios of up to approx1.4 per mil occurred at the same time, indicating large changes in carbon cycling. We suggest that the greenhouse–icehouse transition was closely coupled to the evolution of atmospheric carbon dioxide, and that negative carbon cycle feedbacks may have prevented the permanent establishment of large ice sheets earlier than 34 million years ago. |
format |
Article in Journal/Newspaper |
author |
Tripati, A. K. Backman, J. Elderfield, H. Ferretti, P. |
author_facet |
Tripati, A. K. Backman, J. Elderfield, H. Ferretti, P. |
author_sort |
Tripati, A. K. |
title |
Eocene bipolar glaciation associated with global carbon cycle changes. |
title_short |
Eocene bipolar glaciation associated with global carbon cycle changes. |
title_full |
Eocene bipolar glaciation associated with global carbon cycle changes. |
title_fullStr |
Eocene bipolar glaciation associated with global carbon cycle changes. |
title_full_unstemmed |
Eocene bipolar glaciation associated with global carbon cycle changes. |
title_sort |
eocene bipolar glaciation associated with global carbon cycle changes. |
publishDate |
2005 |
url |
http://eprints.esc.cam.ac.uk/1850/ http://eprints.esc.cam.ac.uk/1850/1/Eocene_bipolar_-_Tripati.pdf https://doi.org/10.1038/nature03874 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
Antarc* Antarctica |
genre_facet |
Antarc* Antarctica |
op_relation |
http://eprints.esc.cam.ac.uk/1850/1/Eocene_bipolar_-_Tripati.pdf Tripati, A. K. and Backman, J. and Elderfield, H. and Ferretti, P. (2005) Eocene bipolar glaciation associated with global carbon cycle changes. Nature, 437. pp. 339-344. DOI https://doi.org/10.1038/nature03874 <https://doi.org/10.1038/nature03874> |
op_doi |
https://doi.org/10.1038/nature03874 |
container_title |
Nature |
container_volume |
436 |
container_issue |
7049 |
container_start_page |
341 |
op_container_end_page |
346 |
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1766026115991732224 |