Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition
At the Eocene-Oligocene Transition (EOT), approximately 34 million years ago, Earth abruptly transitioned to a climate state sufficiently cool for Antarctica to sustain large ice sheets for the first time in tens to hundreds of millions of years. Oxygen isotope records from deep-sea benthic foramini...
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ftunivbergen:oai:bora.uib.no:11250/3108964 2024-01-28T09:59:27+01:00 Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition Taylor, Victoria Emma Wilson, P.A. Bohaty, S.M. Meckler, Anna Nele 2023 application/pdf https://hdl.handle.net/11250/3108964 https://doi.org/10.1029/2023PA004650 eng eng AGU urn:issn:2572-4517 https://hdl.handle.net/11250/3108964 https://doi.org/10.1029/2023PA004650 cristin:2184051 Paleoceanography and Paleoclimatology. 2023, 38 (8), e2023PA004650. Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2023 The Author(s) e2023PA004650 Paleoceanography and Paleoclimatology 38 8 Journal article Peer reviewed 2023 ftunivbergen https://doi.org/10.1029/2023PA004650 2024-01-04T00:08:42Z At the Eocene-Oligocene Transition (EOT), approximately 34 million years ago, Earth abruptly transitioned to a climate state sufficiently cool for Antarctica to sustain large ice sheets for the first time in tens to hundreds of millions of years. Oxygen isotope records from deep-sea benthic foraminifera (δ18Ob) provide the foundation of our understanding of this pivot point in Cenozoic climate history. A deeper insight, however, is hindered by the paucity of independent deep-sea temperature reconstructions and the ongoing challenge of deconvolving the temperature and continental ice volume signals embedded in δ18Ob records. Here we present records of deep-sea temperature change from the eastern equatorial Pacific for the EOT using clumped isotope thermometry, which permits explicit temperature reconstructions independent of seawater chemistry and continental ice volume. Our records suggest that the deep Pacific Ocean cooled markedly at the EOT by 4.7 ± 0.9°C. This decrease in temperature represents the first direct and robust evidence of deep-sea cooling associated with the inception of major Cenozoic glaciation. However, our data also indicate that this major cooling of the deep Pacific Ocean at the EOT was short-lived (∼200 kyrs), with temperatures rebounding to values close to pre-EOT levels by 33.6 Ma. Our calculated record of seawater δ18O suggests that this rebound in ocean temperature occurred despite the continued presence of a large-scale Antarctic ice sheet. This finding suggests a degree of decoupling between deep ocean temperatures in the eastern equatorial Pacific Ocean and the behavior of the newly established Antarctic ice sheet. publishedVersion Article in Journal/Newspaper Antarc* Antarctic Antarctica Ice Sheet University of Bergen: Bergen Open Research Archive (BORA-UiB) Antarctic Pacific Pivot ENVELOPE(-30.239,-30.239,-80.667,-80.667) Paleoceanography and Paleoclimatology 38 8 |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
description |
At the Eocene-Oligocene Transition (EOT), approximately 34 million years ago, Earth abruptly transitioned to a climate state sufficiently cool for Antarctica to sustain large ice sheets for the first time in tens to hundreds of millions of years. Oxygen isotope records from deep-sea benthic foraminifera (δ18Ob) provide the foundation of our understanding of this pivot point in Cenozoic climate history. A deeper insight, however, is hindered by the paucity of independent deep-sea temperature reconstructions and the ongoing challenge of deconvolving the temperature and continental ice volume signals embedded in δ18Ob records. Here we present records of deep-sea temperature change from the eastern equatorial Pacific for the EOT using clumped isotope thermometry, which permits explicit temperature reconstructions independent of seawater chemistry and continental ice volume. Our records suggest that the deep Pacific Ocean cooled markedly at the EOT by 4.7 ± 0.9°C. This decrease in temperature represents the first direct and robust evidence of deep-sea cooling associated with the inception of major Cenozoic glaciation. However, our data also indicate that this major cooling of the deep Pacific Ocean at the EOT was short-lived (∼200 kyrs), with temperatures rebounding to values close to pre-EOT levels by 33.6 Ma. Our calculated record of seawater δ18O suggests that this rebound in ocean temperature occurred despite the continued presence of a large-scale Antarctic ice sheet. This finding suggests a degree of decoupling between deep ocean temperatures in the eastern equatorial Pacific Ocean and the behavior of the newly established Antarctic ice sheet. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Taylor, Victoria Emma Wilson, P.A. Bohaty, S.M. Meckler, Anna Nele |
spellingShingle |
Taylor, Victoria Emma Wilson, P.A. Bohaty, S.M. Meckler, Anna Nele Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition |
author_facet |
Taylor, Victoria Emma Wilson, P.A. Bohaty, S.M. Meckler, Anna Nele |
author_sort |
Taylor, Victoria Emma |
title |
Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition |
title_short |
Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition |
title_full |
Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition |
title_fullStr |
Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition |
title_full_unstemmed |
Transient Deep Ocean Cooling in the Eastern Equatorial Pacific Ocean at the Eocene-Oligocene Transition |
title_sort |
transient deep ocean cooling in the eastern equatorial pacific ocean at the eocene-oligocene transition |
publisher |
AGU |
publishDate |
2023 |
url |
https://hdl.handle.net/11250/3108964 https://doi.org/10.1029/2023PA004650 |
long_lat |
ENVELOPE(-30.239,-30.239,-80.667,-80.667) |
geographic |
Antarctic Pacific Pivot |
geographic_facet |
Antarctic Pacific Pivot |
genre |
Antarc* Antarctic Antarctica Ice Sheet |
genre_facet |
Antarc* Antarctic Antarctica Ice Sheet |
op_source |
e2023PA004650 Paleoceanography and Paleoclimatology 38 8 |
op_relation |
urn:issn:2572-4517 https://hdl.handle.net/11250/3108964 https://doi.org/10.1029/2023PA004650 cristin:2184051 Paleoceanography and Paleoclimatology. 2023, 38 (8), e2023PA004650. |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no Copyright 2023 The Author(s) |
op_doi |
https://doi.org/10.1029/2023PA004650 |
container_title |
Paleoceanography and Paleoclimatology |
container_volume |
38 |
container_issue |
8 |
_version_ |
1789335924364017664 |