Lyndsey R. Fox
Temperature Gradients Across the Pacific Ocean During the Middle Miocene
Fox, Lyndsey R.; Wade, Bridget S.; Holbourn, Ann; Leng, Melanie J.; Bhatia, Rehemat
Authors
Bridget S. Wade
Ann Holbourn
Professor MELANIE LENG Melanie.Leng@nottingham.ac.uk
PROFESSOR OF ISOTOPE GEOSCIENCES
Rehemat Bhatia
Abstract
Sea surface temperatures (SSTs) of the tropical Pacific Ocean exert powerful controls on regional and global climates. Previous studies have suggested that during warm climate phases, the east-west temperature gradient collapsed. To date, there has been no high-resolution reconstruction of sea surface conditions in both the east and west Pacific Ocean during the Miocene Climate Optimum (MCO) and across the middle Miocene climate transition (MMCT); therefore, our understanding of the mean oceanographic state during this major global climatic shift is limited. Here, we present new SST reconstructions for the eastern Pacific Ocean (15.5–13.3Ma) which show a clear east-west temperature gradient of ∼4°C during the warmest interval of the Neogene, implying that the oceanographic processes that produce the modern gradient were present and active. There is no shift in the east-west gradient across the MMCT indicating that the gradient was not impacted by global cooling and ice growth. We find a 2°C sea surface cooling in the eastern equatorial Pacific, that lags the benthic foraminiferal δ18O positive shift by 150kyr, indicating that tropical temperature did not decrease synchronously with the expansion of the Antarctic ice sheet. Reconstructed variations in the δ18O composition of seawater, determined by combining our Mg/Ca and δ18O records, reveal a freshening in the eastern Pacific Ocean after 13.8Ma, suggesting changes in the hydrological cycle and in tropical fronts in response to the new icehouse regime.
Citation
Fox, L. R., Wade, B. S., Holbourn, A., Leng, M. J., & Bhatia, R. (2021). Temperature Gradients Across the Pacific Ocean During the Middle Miocene. Paleoceanography and Paleoclimatology, 36(6), 1-16. https://doi.org/10.1029/2020PA003924
Journal Article Type | Article |
---|---|
Acceptance Date | May 20, 2021 |
Online Publication Date | Jun 7, 2021 |
Publication Date | Jun 1, 2021 |
Deposit Date | Jul 21, 2021 |
Publicly Available Date | Jul 21, 2021 |
Journal | Paleoceanography and Paleoclimatology |
Print ISSN | 2572-4517 |
Electronic ISSN | 2572-4525 |
Peer Reviewed | Peer Reviewed |
Volume | 36 |
Issue | 6 |
Article Number | e2020PA003924 |
Pages | 1-16 |
DOI | https://doi.org/10.1029/2020PA003924 |
Keywords | Paleontology, Atmospheric Science, Oceanography |
Public URL | https://nottingham-repository.worktribe.com/output/5671178 |
Publisher URL | https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2020PA003924 |
Files
Temperature Gradients Across the Pacific Ocean During the Middle Miocene
(1.5 Mb)
PDF
Publisher Licence URL
https://creativecommons.org/licenses/by/4.0/
You might also like
South Georgia marine productivity over the past 15 ka and implications for glacial evolution
(2024)
Journal Article
Downloadable Citations
About Repository@Nottingham
Administrator e-mail: discovery-access-systems@nottingham.ac.uk
This application uses the following open-source libraries:
SheetJS Community Edition
Apache License Version 2.0 (http://www.apache.org/licenses/)
PDF.js
Apache License Version 2.0 (http://www.apache.org/licenses/)
Font Awesome
SIL OFL 1.1 (http://scripts.sil.org/OFL)
MIT License (http://opensource.org/licenses/mit-license.html)
CC BY 3.0 ( http://creativecommons.org/licenses/by/3.0/)
Powered by Worktribe © 2025
Advanced Search