Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum
The deep Pacific Ocean holds the largest oceanic reservoir of carbon which may interchange with the atmosphere on climatologically important timescales. The circulation of the deep Pacific during the Last Glacial Maximum (LGM), however, is not well understood. Neodymium (Nd) isotopes of ferromangane...
Published in: | Earth and Planetary Science Letters |
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ftucambridgeesc:oai:eprints.esc.cam.ac.uk:3828 2023-05-15T17:25:29+02:00 Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum Hu, Rong Piotrowski, Alexander M. Bostock, Helen C. Crowhurst, Simon Rennie, Victoria 2016-08 text http://eprints.esc.cam.ac.uk/3828/ http://eprints.esc.cam.ac.uk/3828/1/1-s2.0-S0012821X16302205-main.pdf http://eprints.esc.cam.ac.uk/3828/7/mmc1.xlsx http://www.sciencedirect.com/science/article/pii/S0012821X16302205 https://doi.org/10.1016/j.epsl.2016.05.011 en eng Elsevier http://eprints.esc.cam.ac.uk/3828/1/1-s2.0-S0012821X16302205-main.pdf http://eprints.esc.cam.ac.uk/3828/7/mmc1.xlsx Hu, Rong and Piotrowski, Alexander M. and Bostock, Helen C. and Crowhurst, Simon and Rennie, Victoria (2016) Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum. Earth and Planetary Science Letters, 447. pp. 130-138. ISSN 0012-821X DOI https://doi.org/10.1016/j.epsl.2016.05.011 <https://doi.org/10.1016/j.epsl.2016.05.011> 01 - Climate Change and Earth-Ocean Atmosphere Systems Article PeerReviewed 2016 ftucambridgeesc https://doi.org/10.1016/j.epsl.2016.05.011 2020-08-27T18:09:49Z The deep Pacific Ocean holds the largest oceanic reservoir of carbon which may interchange with the atmosphere on climatologically important timescales. The circulation of the deep Pacific during the Last Glacial Maximum (LGM), however, is not well understood. Neodymium (Nd) isotopes of ferromanganese oxide coatings precipitated on planktonic foraminifera are a valuable proxy for deep ocean water mass reconstruction in paleoceanography. In this study, we present Nd isotope compositions ( ε Nd ) of planktonic foraminifera for the Holocene and the LGM obtained from 55 new sites widely distributed in the Pacific Ocean. The Holocene planktonic foraminiferal ε Nd results agree with the proximal seawater data, indicating that they provide a reliable record of modern bottom water Nd isotopes in the deep Pacific. There is a good correlation between foraminiferal ε Nd and seawater phosphate concentrations ( R 2 = 0.80 ), but poorer correlation with silicate ( R 2 = 0.37 ). Our interpretation is that the radiogenic Nd isotope is added to the deep open Pacific through particle release from the upper ocean during deep water mass advection and aging. The data thus also imply the Nd isotopes in the Pacific are not likely to be controlled by silicate cycling. In the North Pacific, the glacial Nd isotopic compositions are similar to the Holocene values, indicating that the Nd isotope composition of North Pacific Deep Water (NPDW) remained constant (-3.5 to -4). During the LGM, the southwest Pacific cores throughout the water column show higher ε Nd corroborating previous studies which suggested a reduced inflow of North Atlantic Deep Water to the Pacific. However, the western equatorial Pacific deep water does not record a corresponding radiogenic excursion, implying reduced radiogenic boundary inputs during the LGM probably due to a shorter duration of seawater-particle interaction in a stronger glacial deep boundary current. A significant negative glacial ε Nd excursion is evident in mid-depth (1-2 km) cores of the eastern equatorial Pacific (EEP) which may suggest a stronger influence of NPDW return flow to the core sites and decreased local input in the EEP. Taken together, our Nd records do not support a dynamically slower glacial Pacific overturning circulation, and imply that the increased carbon inventory of Pacific deep water might be due to poor high latitude air-sea exchange and increased biological pump efficiency in glacial times. Article in Journal/Newspaper North Atlantic Deep Water North Atlantic Planktonic foraminifera University of Cambridge, Department of Earth Sciences: ESC Publications Pacific Earth and Planetary Science Letters 447 130 138 |
institution |
Open Polar |
collection |
University of Cambridge, Department of Earth Sciences: ESC Publications |
op_collection_id |
ftucambridgeesc |
language |
English |
topic |
01 - Climate Change and Earth-Ocean Atmosphere Systems |
spellingShingle |
01 - Climate Change and Earth-Ocean Atmosphere Systems Hu, Rong Piotrowski, Alexander M. Bostock, Helen C. Crowhurst, Simon Rennie, Victoria Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum |
topic_facet |
01 - Climate Change and Earth-Ocean Atmosphere Systems |
description |
The deep Pacific Ocean holds the largest oceanic reservoir of carbon which may interchange with the atmosphere on climatologically important timescales. The circulation of the deep Pacific during the Last Glacial Maximum (LGM), however, is not well understood. Neodymium (Nd) isotopes of ferromanganese oxide coatings precipitated on planktonic foraminifera are a valuable proxy for deep ocean water mass reconstruction in paleoceanography. In this study, we present Nd isotope compositions ( ε Nd ) of planktonic foraminifera for the Holocene and the LGM obtained from 55 new sites widely distributed in the Pacific Ocean. The Holocene planktonic foraminiferal ε Nd results agree with the proximal seawater data, indicating that they provide a reliable record of modern bottom water Nd isotopes in the deep Pacific. There is a good correlation between foraminiferal ε Nd and seawater phosphate concentrations ( R 2 = 0.80 ), but poorer correlation with silicate ( R 2 = 0.37 ). Our interpretation is that the radiogenic Nd isotope is added to the deep open Pacific through particle release from the upper ocean during deep water mass advection and aging. The data thus also imply the Nd isotopes in the Pacific are not likely to be controlled by silicate cycling. In the North Pacific, the glacial Nd isotopic compositions are similar to the Holocene values, indicating that the Nd isotope composition of North Pacific Deep Water (NPDW) remained constant (-3.5 to -4). During the LGM, the southwest Pacific cores throughout the water column show higher ε Nd corroborating previous studies which suggested a reduced inflow of North Atlantic Deep Water to the Pacific. However, the western equatorial Pacific deep water does not record a corresponding radiogenic excursion, implying reduced radiogenic boundary inputs during the LGM probably due to a shorter duration of seawater-particle interaction in a stronger glacial deep boundary current. A significant negative glacial ε Nd excursion is evident in mid-depth (1-2 km) cores of the eastern equatorial Pacific (EEP) which may suggest a stronger influence of NPDW return flow to the core sites and decreased local input in the EEP. Taken together, our Nd records do not support a dynamically slower glacial Pacific overturning circulation, and imply that the increased carbon inventory of Pacific deep water might be due to poor high latitude air-sea exchange and increased biological pump efficiency in glacial times. |
format |
Article in Journal/Newspaper |
author |
Hu, Rong Piotrowski, Alexander M. Bostock, Helen C. Crowhurst, Simon Rennie, Victoria |
author_facet |
Hu, Rong Piotrowski, Alexander M. Bostock, Helen C. Crowhurst, Simon Rennie, Victoria |
author_sort |
Hu, Rong |
title |
Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum |
title_short |
Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum |
title_full |
Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum |
title_fullStr |
Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum |
title_full_unstemmed |
Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum |
title_sort |
variability of neodymium isotopes associated with planktonic foraminifera in the pacific ocean during the holocene and last glacial maximum |
publisher |
Elsevier |
publishDate |
2016 |
url |
http://eprints.esc.cam.ac.uk/3828/ http://eprints.esc.cam.ac.uk/3828/1/1-s2.0-S0012821X16302205-main.pdf http://eprints.esc.cam.ac.uk/3828/7/mmc1.xlsx http://www.sciencedirect.com/science/article/pii/S0012821X16302205 https://doi.org/10.1016/j.epsl.2016.05.011 |
geographic |
Pacific |
geographic_facet |
Pacific |
genre |
North Atlantic Deep Water North Atlantic Planktonic foraminifera |
genre_facet |
North Atlantic Deep Water North Atlantic Planktonic foraminifera |
op_relation |
http://eprints.esc.cam.ac.uk/3828/1/1-s2.0-S0012821X16302205-main.pdf http://eprints.esc.cam.ac.uk/3828/7/mmc1.xlsx Hu, Rong and Piotrowski, Alexander M. and Bostock, Helen C. and Crowhurst, Simon and Rennie, Victoria (2016) Variability of neodymium isotopes associated with planktonic foraminifera in the Pacific Ocean during the Holocene and Last Glacial Maximum. Earth and Planetary Science Letters, 447. pp. 130-138. ISSN 0012-821X DOI https://doi.org/10.1016/j.epsl.2016.05.011 <https://doi.org/10.1016/j.epsl.2016.05.011> |
op_doi |
https://doi.org/10.1016/j.epsl.2016.05.011 |
container_title |
Earth and Planetary Science Letters |
container_volume |
447 |
container_start_page |
130 |
op_container_end_page |
138 |
_version_ |
1766116931793846272 |