Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum
Highlights • Robust increase in silt size at 5 ka reflects increased flow of Labrador Sea Water. • Ice-rafted debris likely affects on the Labrador Slope during the last deglacial. • End member modeling and corrections provide insight into deglacial sediments. Abstract The Labrador Sea is a vital re...
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Online Access: | https://oceanrep.geomar.de/id/eprint/46282/ https://oceanrep.geomar.de/id/eprint/46282/1/Hoffmann.pdf https://doi.org/10.1016/j.quascirev.2018.12.028 |
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ftoceanrep:oai:oceanrep.geomar.de:46282 2023-05-15T17:06:00+02:00 Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum Hoffmann, Sharon S. Dalsing, Risa E. Murphy, Sarah C. 2019 text https://oceanrep.geomar.de/id/eprint/46282/ https://oceanrep.geomar.de/id/eprint/46282/1/Hoffmann.pdf https://doi.org/10.1016/j.quascirev.2018.12.028 en eng Elsevier https://oceanrep.geomar.de/id/eprint/46282/1/Hoffmann.pdf Hoffmann, S. S. , Dalsing, R. E. and Murphy, S. C. (2019) Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum. Quaternary Science Reviews, 206 . pp. 99-110. DOI 10.1016/j.quascirev.2018.12.028 <https://doi.org/10.1016/j.quascirev.2018.12.028>. doi:10.1016/j.quascirev.2018.12.028 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 2019 ftoceanrep https://doi.org/10.1016/j.quascirev.2018.12.028 2023-04-07T15:44:49Z Highlights • Robust increase in silt size at 5 ka reflects increased flow of Labrador Sea Water. • Ice-rafted debris likely affects on the Labrador Slope during the last deglacial. • End member modeling and corrections provide insight into deglacial sediments. Abstract The Labrador Sea is a vital region for the Atlantic Meridional Overturning Circulation (AMOC), where overflow waters from the Nordic Seas mix with locally produced Labrador Sea Water (LSW), before exiting to the interior of the Atlantic Ocean. The dynamical sedimentary proxy of mean sortable silt size ( ) can give information on past changes in deep water circulation speed and the strength of AMOC. We have produced records from two core sites at depths between 1500 and 2000 m on the continental slope east of Newfoundland, to reconstruct changes in intermediate depth water circulation speed, including Glacial North Atlantic Intermediate Water and Labrador Sea Water over the past 22,000 years. Increases in appear to coincide with much of the deglaciation as well as the mid-late Holocene. End-member modeling suggests that ice-rafted debris (IRD) is an important factor in interpreting during the deglaciation. We find that a robust increase in is likely unrelated to IRD during the past 5 ka, and probably reflects increased flow at intermediate depths due to local production of LSW strengthening as Nordic Seas overflows weakened at this depth. Our results highlight both the complications of producing records in IRD-rich, slope environments and the promise that this proxy nevertheless has for reconstructing dynamical changes in deep ocean currents. Article in Journal/Newspaper Labrador Sea Newfoundland Nordic Seas North Atlantic OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Newfoundland Quaternary Science Reviews 206 99 110 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Highlights • Robust increase in silt size at 5 ka reflects increased flow of Labrador Sea Water. • Ice-rafted debris likely affects on the Labrador Slope during the last deglacial. • End member modeling and corrections provide insight into deglacial sediments. Abstract The Labrador Sea is a vital region for the Atlantic Meridional Overturning Circulation (AMOC), where overflow waters from the Nordic Seas mix with locally produced Labrador Sea Water (LSW), before exiting to the interior of the Atlantic Ocean. The dynamical sedimentary proxy of mean sortable silt size ( ) can give information on past changes in deep water circulation speed and the strength of AMOC. We have produced records from two core sites at depths between 1500 and 2000 m on the continental slope east of Newfoundland, to reconstruct changes in intermediate depth water circulation speed, including Glacial North Atlantic Intermediate Water and Labrador Sea Water over the past 22,000 years. Increases in appear to coincide with much of the deglaciation as well as the mid-late Holocene. End-member modeling suggests that ice-rafted debris (IRD) is an important factor in interpreting during the deglaciation. We find that a robust increase in is likely unrelated to IRD during the past 5 ka, and probably reflects increased flow at intermediate depths due to local production of LSW strengthening as Nordic Seas overflows weakened at this depth. Our results highlight both the complications of producing records in IRD-rich, slope environments and the promise that this proxy nevertheless has for reconstructing dynamical changes in deep ocean currents. |
format |
Article in Journal/Newspaper |
author |
Hoffmann, Sharon S. Dalsing, Risa E. Murphy, Sarah C. |
spellingShingle |
Hoffmann, Sharon S. Dalsing, Risa E. Murphy, Sarah C. Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum |
author_facet |
Hoffmann, Sharon S. Dalsing, Risa E. Murphy, Sarah C. |
author_sort |
Hoffmann, Sharon S. |
title |
Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum |
title_short |
Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum |
title_full |
Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum |
title_fullStr |
Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum |
title_full_unstemmed |
Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum |
title_sort |
sortable silt records of intermediate-depth circulation and sedimentation in the southwest labrador sea since the last glacial maximum |
publisher |
Elsevier |
publishDate |
2019 |
url |
https://oceanrep.geomar.de/id/eprint/46282/ https://oceanrep.geomar.de/id/eprint/46282/1/Hoffmann.pdf https://doi.org/10.1016/j.quascirev.2018.12.028 |
geographic |
Newfoundland |
geographic_facet |
Newfoundland |
genre |
Labrador Sea Newfoundland Nordic Seas North Atlantic |
genre_facet |
Labrador Sea Newfoundland Nordic Seas North Atlantic |
op_relation |
https://oceanrep.geomar.de/id/eprint/46282/1/Hoffmann.pdf Hoffmann, S. S. , Dalsing, R. E. and Murphy, S. C. (2019) Sortable silt records of intermediate-depth circulation and sedimentation in the Southwest Labrador Sea since the Last Glacial Maximum. Quaternary Science Reviews, 206 . pp. 99-110. DOI 10.1016/j.quascirev.2018.12.028 <https://doi.org/10.1016/j.quascirev.2018.12.028>. doi:10.1016/j.quascirev.2018.12.028 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1016/j.quascirev.2018.12.028 |
container_title |
Quaternary Science Reviews |
container_volume |
206 |
container_start_page |
99 |
op_container_end_page |
110 |
_version_ |
1766060892064055296 |