Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study
The sensitivity of the neodymium isotopic composition (ϵNd) to tectonic rearrangements of seaways is investigated using an Earth System Model of Intermediate Complexity. The shoaling and closure of the Central American Seaway (CAS) is simulated, as well as the opening and deepening of Drake Passage...
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Online Access: | https://boris.unibe.ch/62576/1/palo20165.pdf https://boris.unibe.ch/62576/ |
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ftunivbern:oai:boris.unibe.ch:62576 2023-08-20T04:06:10+02:00 Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study Pfister, Patrik L. Stocker, Thomas F. Rempfer, Johannes Ritz, Stefan P. 2014-12-18 application/pdf https://boris.unibe.ch/62576/1/palo20165.pdf https://boris.unibe.ch/62576/ eng eng American Geophysical Union https://boris.unibe.ch/62576/ info:eu-repo/semantics/openAccess Pfister, Patrik L.; Stocker, Thomas F.; Rempfer, Johannes; Ritz, Stefan P. (2014). Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study. Paleoceanography, 29(12), pp. 1214-1237. American Geophysical Union 10.1002/2014PA002666 <http://dx.doi.org/10.1002/2014PA002666> 530 Physics info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion PeerReviewed 2014 ftunivbern https://doi.org/10.1002/2014PA002666 2023-07-31T21:13:49Z The sensitivity of the neodymium isotopic composition (ϵNd) to tectonic rearrangements of seaways is investigated using an Earth System Model of Intermediate Complexity. The shoaling and closure of the Central American Seaway (CAS) is simulated, as well as the opening and deepening of Drake Passage (DP). Multiple series of equilibrium simulations with various intermediate depths are performed for both seaways, providing insight into ϵNd and circulation responses to progressive throughflow evolutions. Furthermore, the sensitivity of these responses to the Atlantic Meridional Overturning Circulation (AMOC) and the neodymium boundary source is examined. Modeled ϵNd changes are compared to sediment core and ferromanganese (Fe-Mn) crust data. The model results indicate that the North Atlantic ϵNd response to the CAS shoaling is highly dependent on the AMOC state, i.e., on the AMOC strength before the shoaling to shallow depths (preclosure). Three scenarios based on different AMOC forcings are discussed, of which the model-data agreement favors a shallow preclosure (Miocene) AMOC (∼6 Sv). The DP opening causes a rather complex circulation response, resulting in an initial South Atlantic ϵNd decrease preceding a larger increase. This feature may be specific to our model setup, which induces a vigorous CAS throughflow that is strongly anticorrelated to the DP throughflow. In freshwater experiments following the DP deepening, ODP Site 1090 is mainly influenced by AMOC and DP throughflow changes, while ODP Site 689 is more strongly influenced by Southern Ocean Meridional Overturning Circulation and CAS throughflow changes. The boundary source uncertainty is largest for shallow seaways and at shallow sites. Article in Journal/Newspaper Drake Passage North Atlantic Southern Ocean BORIS (Bern Open Repository and Information System, University of Bern) Drake Passage Southern Ocean Paleoceanography 29 12 1214 1237 |
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Open Polar |
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BORIS (Bern Open Repository and Information System, University of Bern) |
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ftunivbern |
language |
English |
topic |
530 Physics |
spellingShingle |
530 Physics Pfister, Patrik L. Stocker, Thomas F. Rempfer, Johannes Ritz, Stefan P. Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study |
topic_facet |
530 Physics |
description |
The sensitivity of the neodymium isotopic composition (ϵNd) to tectonic rearrangements of seaways is investigated using an Earth System Model of Intermediate Complexity. The shoaling and closure of the Central American Seaway (CAS) is simulated, as well as the opening and deepening of Drake Passage (DP). Multiple series of equilibrium simulations with various intermediate depths are performed for both seaways, providing insight into ϵNd and circulation responses to progressive throughflow evolutions. Furthermore, the sensitivity of these responses to the Atlantic Meridional Overturning Circulation (AMOC) and the neodymium boundary source is examined. Modeled ϵNd changes are compared to sediment core and ferromanganese (Fe-Mn) crust data. The model results indicate that the North Atlantic ϵNd response to the CAS shoaling is highly dependent on the AMOC state, i.e., on the AMOC strength before the shoaling to shallow depths (preclosure). Three scenarios based on different AMOC forcings are discussed, of which the model-data agreement favors a shallow preclosure (Miocene) AMOC (∼6 Sv). The DP opening causes a rather complex circulation response, resulting in an initial South Atlantic ϵNd decrease preceding a larger increase. This feature may be specific to our model setup, which induces a vigorous CAS throughflow that is strongly anticorrelated to the DP throughflow. In freshwater experiments following the DP deepening, ODP Site 1090 is mainly influenced by AMOC and DP throughflow changes, while ODP Site 689 is more strongly influenced by Southern Ocean Meridional Overturning Circulation and CAS throughflow changes. The boundary source uncertainty is largest for shallow seaways and at shallow sites. |
format |
Article in Journal/Newspaper |
author |
Pfister, Patrik L. Stocker, Thomas F. Rempfer, Johannes Ritz, Stefan P. |
author_facet |
Pfister, Patrik L. Stocker, Thomas F. Rempfer, Johannes Ritz, Stefan P. |
author_sort |
Pfister, Patrik L. |
title |
Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study |
title_short |
Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study |
title_full |
Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study |
title_fullStr |
Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study |
title_full_unstemmed |
Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study |
title_sort |
influence of the central american seaway and drake passage on ocean circulation and neodymium isotopes: a model study |
publisher |
American Geophysical Union |
publishDate |
2014 |
url |
https://boris.unibe.ch/62576/1/palo20165.pdf https://boris.unibe.ch/62576/ |
geographic |
Drake Passage Southern Ocean |
geographic_facet |
Drake Passage Southern Ocean |
genre |
Drake Passage North Atlantic Southern Ocean |
genre_facet |
Drake Passage North Atlantic Southern Ocean |
op_source |
Pfister, Patrik L.; Stocker, Thomas F.; Rempfer, Johannes; Ritz, Stefan P. (2014). Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study. Paleoceanography, 29(12), pp. 1214-1237. American Geophysical Union 10.1002/2014PA002666 <http://dx.doi.org/10.1002/2014PA002666> |
op_relation |
https://boris.unibe.ch/62576/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1002/2014PA002666 |
container_title |
Paleoceanography |
container_volume |
29 |
container_issue |
12 |
container_start_page |
1214 |
op_container_end_page |
1237 |
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1774717110532964352 |