A deep Tasman outflow of Pacific waters during the last glacial period
Abstract
The interoceanic exchange of water masses is modulated by flow through key oceanic choke points in the Drake Passage, the Indonesian Seas, south of Africa, and south of Tasmania. Here, we use the neodymium isotope signature (ε_(Nd)) of cold-water coral skeletons from intermediate depths (1460‒1689 m) to trace circulation changes south of Tasmania during the last glacial period. The key feature of our dataset is a long-term trend towards radiogenic εNd values of ~−4.6 during the Last Glacial Maximum and Heinrich Stadial 1, which are clearly distinct from contemporaneous Southern Ocean ε_(Nd) of ~−7. When combined with previously published radiocarbon data from the same corals, our results indicate that a unique radiogenic and young water mass was present during this time. This scenario can be explained by a more vigorous Pacific overturning circulation that supported a deeper outflow of Pacific waters, including North Pacific Intermediate Water, through the Tasman Sea.
Additional Information
© The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. Received 29 May 2021; Accepted 06 June 2022; Published 30 June 2022. We acknowledge the science teams and crews of expedition TN-228. K. Kreissig and B. Coles are thanked for their help with laboratory analyses. The authors acknowledge financial support from the Grantham Institute of Climate Change and the Environment (T.v.d.F. and T.S.), the Ministry for Science and Culture of the State of Lower Saxony (T.S.), Marie Curie Reintegration grant IRG 230828 (T.v.d.F.), Leverhulme Trust grant RPG-398 (T.v.d.F.), Natural Environment Research Council grants NE/F016751/1 (T.v.d.F.), NE/N001141/1 (T.v.d.F. and D.J.W.), and NE/T011440/1 (D.J.W.), and National Science Foundation grant OCE-1503129 (J.F.A. and S.K.V.H.). Open Access funding is enabled by the DFG open access publication fund and the Carl von Ossietzky University Oldenburg. Data availability: The data generated in this study are provided in the Source Data file and available in the figshare database under https://doi.org/10.6084/m9.figshare.19355633. Contributions: T.S., D.J.W., and T.v.d.F. designed the research and led the draft of the manuscript. T.S. carried out the Nd isotope analysis. J.F.A. and S.K.V.H. provided the sample material and the U-Th dates. D.J.W. and S.K.V.H. collected Nd fractions during Pb and U-Th ion-exchange chromatography, respectively. All authors contributed to the data interpretation and writing the manuscript. The authors declare no competing interests. Peer review information: Nature Communications thanks Brian Haley and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.Attached Files
Published - s41467-022-31116-7.pdf
Supplemental Material - 41467_2022_31116_MOESM1_ESM.pdf
Supplemental Material - 41467_2022_31116_MOESM2_ESM.xlsx
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Additional details
- PMCID
- PMC9246942
- Eprint ID
- 115448
- Resolver ID
- CaltechAUTHORS:20220711-15247300
- Grantham Institute of Climate Change and the Environment
- Ministry for Science and Culture of the State of Lower Saxony
- 230828
- Marie Curie Fellowship
- RPG-398
- Leverhulme Trust
- NE/F016751/1
- Natural Environment Research Council (NERC)
- NE/N001141/1
- Natural Environment Research Council (NERC)
- NE/T011440/1
- Natural Environment Research Council (NERC)
- OCE-1503129
- NSF
- Deutsche Forschungsgemeinschaft (DFG)
- Carl von Ossietzky University Oldenburg
- Created
-
2022-07-11Created from EPrint's datestamp field
- Updated
-
2022-07-11Created from EPrint's last_modified field
- Caltech groups
- Division of Geological and Planetary Sciences