Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective
Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 29 (2014): 1072–1093, doi:10.1002/2014PA002674. The last deglaciation was cha...
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Online Access: | https://hdl.handle.net/1912/7108 |
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ftwhoas:oai:darchive.mblwhoilibrary.org:1912/7108 2023-05-15T16:30:18+02:00 Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective Wilson, David J. Crocket, Kirsty C. van de Flierdt, Tina Robinson, Laura F. Adkins, Jess F. 2014-11-20 application/pdf application/msword application/vnd.ms-excel https://hdl.handle.net/1912/7108 en_US eng John Wiley & Sons https://doi.org/10.1002/2014PA002674 Paleoceanography 29 (2014): 1072–1093 https://hdl.handle.net/1912/7108 doi:10.1002/2014PA002674 Paleoceanography 29 (2014): 1072–1093 doi:10.1002/2014PA002674 Heinrich stadial Deglaciation Atlantic meridional overturning circulation Neodymium isotopes Radiocarbon Deep sea corals Article 2014 ftwhoas https://doi.org/10.1002/2014PA002674 2022-05-28T22:59:16Z Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 29 (2014): 1072–1093, doi:10.1002/2014PA002674. The last deglaciation was characterized by a series of millennial-scale climate events that have been linked to deep ocean variability. While often implied in interpretations, few direct constraints exist on circulation changes at mid-depths. Here we provide new constraints on the variability of deglacial mid-depth circulation using combined radiocarbon and neodymium isotopes in 24 North Atlantic deep-sea corals. Their aragonite skeletons have been dated by uranium-series, providing absolute ages and the resolution to record centennial-scale changes, while transects spanning the lifetime of a single coral allow subcentennial tracer reconstruction. Our results reveal that rapid fluctuations of water mass sourcing and radiocarbon affected the mid-depth water column (1.7–2.5 km) on timescales of less than 100 years during the latter half of Heinrich Stadial 1. The neodymium isotopic variability (−14.5 to −11.0) ranges from the composition of the modern northern-sourced waters towards more radiogenic compositions, suggesting the presence of a greater southern-sourced component at some times. However, in detail, simple two-component mixing between well-ventilated northern-sourced and radiocarbon-depleted southern-sourced water masses cannot explain all our data. Instead, corals from ~15.0 ka and ~15.8 ka may record variability between southern-sourced intermediate waters and radiocarbon-depleted northern-sourced waters, unless there was a major shift in the neodymium isotopic composition of the northern end-member. In order to explain the rapid shift towards the most depleted radiocarbon values at ~15.4 ka, we suggest a different mixing scenario involving either radiocarbon-depleted deep water from the Greenland-Iceland-Norwegian Seas or a ... Article in Journal/Newspaper Greenland Iceland North Atlantic Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) Greenland Paleoceanography 29 11 1072 1093 |
institution |
Open Polar |
collection |
Woods Hole Scientific Community: WHOAS (Woods Hole Open Access Server) |
op_collection_id |
ftwhoas |
language |
English |
topic |
Heinrich stadial Deglaciation Atlantic meridional overturning circulation Neodymium isotopes Radiocarbon Deep sea corals |
spellingShingle |
Heinrich stadial Deglaciation Atlantic meridional overturning circulation Neodymium isotopes Radiocarbon Deep sea corals Wilson, David J. Crocket, Kirsty C. van de Flierdt, Tina Robinson, Laura F. Adkins, Jess F. Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective |
topic_facet |
Heinrich stadial Deglaciation Atlantic meridional overturning circulation Neodymium isotopes Radiocarbon Deep sea corals |
description |
Author Posting. © American Geophysical Union, 2014. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Paleoceanography 29 (2014): 1072–1093, doi:10.1002/2014PA002674. The last deglaciation was characterized by a series of millennial-scale climate events that have been linked to deep ocean variability. While often implied in interpretations, few direct constraints exist on circulation changes at mid-depths. Here we provide new constraints on the variability of deglacial mid-depth circulation using combined radiocarbon and neodymium isotopes in 24 North Atlantic deep-sea corals. Their aragonite skeletons have been dated by uranium-series, providing absolute ages and the resolution to record centennial-scale changes, while transects spanning the lifetime of a single coral allow subcentennial tracer reconstruction. Our results reveal that rapid fluctuations of water mass sourcing and radiocarbon affected the mid-depth water column (1.7–2.5 km) on timescales of less than 100 years during the latter half of Heinrich Stadial 1. The neodymium isotopic variability (−14.5 to −11.0) ranges from the composition of the modern northern-sourced waters towards more radiogenic compositions, suggesting the presence of a greater southern-sourced component at some times. However, in detail, simple two-component mixing between well-ventilated northern-sourced and radiocarbon-depleted southern-sourced water masses cannot explain all our data. Instead, corals from ~15.0 ka and ~15.8 ka may record variability between southern-sourced intermediate waters and radiocarbon-depleted northern-sourced waters, unless there was a major shift in the neodymium isotopic composition of the northern end-member. In order to explain the rapid shift towards the most depleted radiocarbon values at ~15.4 ka, we suggest a different mixing scenario involving either radiocarbon-depleted deep water from the Greenland-Iceland-Norwegian Seas or a ... |
format |
Article in Journal/Newspaper |
author |
Wilson, David J. Crocket, Kirsty C. van de Flierdt, Tina Robinson, Laura F. Adkins, Jess F. |
author_facet |
Wilson, David J. Crocket, Kirsty C. van de Flierdt, Tina Robinson, Laura F. Adkins, Jess F. |
author_sort |
Wilson, David J. |
title |
Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective |
title_short |
Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective |
title_full |
Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective |
title_fullStr |
Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective |
title_full_unstemmed |
Dynamic intermediate ocean circulation in the North Atlantic during Heinrich Stadial 1 : a radiocarbon and neodymium isotope perspective |
title_sort |
dynamic intermediate ocean circulation in the north atlantic during heinrich stadial 1 : a radiocarbon and neodymium isotope perspective |
publisher |
John Wiley & Sons |
publishDate |
2014 |
url |
https://hdl.handle.net/1912/7108 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Iceland North Atlantic |
genre_facet |
Greenland Iceland North Atlantic |
op_source |
Paleoceanography 29 (2014): 1072–1093 doi:10.1002/2014PA002674 |
op_relation |
https://doi.org/10.1002/2014PA002674 Paleoceanography 29 (2014): 1072–1093 https://hdl.handle.net/1912/7108 doi:10.1002/2014PA002674 |
op_doi |
https://doi.org/10.1002/2014PA002674 |
container_title |
Paleoceanography |
container_volume |
29 |
container_issue |
11 |
container_start_page |
1072 |
op_container_end_page |
1093 |
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1766020024352374784 |