Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies
We attempt to assess the Holocene surface-subsurface seawater density gradient on millennial time scale based on the reconstruction of potential density (σθ) by combining data from dinoflagellate cyst assemblages and planktic foraminiferal (Neogloboquadrina pachyderma (s)) stable oxygen isotopes (δ1...
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Language: | English |
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AGU (American Geophysical Union)
2016
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Online Access: | https://oceanrep.geomar.de/id/eprint/32941/ https://oceanrep.geomar.de/id/eprint/32941/1/palo20300.pdf https://doi.org/10.1002/2015PA002815 |
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ftoceanrep:oai:oceanrep.geomar.de:32941 2023-05-15T17:14:57+02:00 Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies Van Nieuwenhove, Nicolas Hillaire-Marcel, Claude Bauch, Henning A. de Vernal, Anne 2016-03 text https://oceanrep.geomar.de/id/eprint/32941/ https://oceanrep.geomar.de/id/eprint/32941/1/palo20300.pdf https://doi.org/10.1002/2015PA002815 en eng AGU (American Geophysical Union) Wiley https://oceanrep.geomar.de/id/eprint/32941/1/palo20300.pdf Van Nieuwenhove, N. , Hillaire-Marcel, C., Bauch, H. A. and de Vernal, A. (2016) Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies. Paleoceanography, 31 (3). pp. 380-398. DOI 10.1002/2015PA002815 <https://doi.org/10.1002/2015PA002815>. doi:10.1002/2015PA002815 info:eu-repo/semantics/restrictedAccess Article PeerReviewed info:eu-repo/semantics/article 2016 ftoceanrep https://doi.org/10.1002/2015PA002815 2023-04-07T15:25:51Z We attempt to assess the Holocene surface-subsurface seawater density gradient on millennial time scale based on the reconstruction of potential density (σθ) by combining data from dinoflagellate cyst assemblages and planktic foraminiferal (Neogloboquadrina pachyderma (s)) stable oxygen isotopes (δ18Oc). Following several calibration exercises, the likeliness of favorable seasonal preconditioning to open ocean convection is evaluated. The reconstructed σθ values reveal unfavorable conditions for vertical convection in the western Nordic Seas prior to ~7–6.5 ka B.P., with a westward increase and persistence of surface water buoyancy. Active overturning became more likely after 6.5 ka B.P. as suggested by a reduced and recurrently inverted vertical σθ gradient, while intermittent eastward spreading of lower density surface waters continued to modulate the area of potential overturning. Despite some reservation regarding the accuracy of the σθ values reconstructed, the documentation of relative changes of σθ gradients through time and space is suggested as a helpful tool for the appraisal of past overturning likeliness. Article in Journal/Newspaper Neogloboquadrina pachyderma Nordic Seas OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Paleoceanography 31 3 380 398 |
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Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
We attempt to assess the Holocene surface-subsurface seawater density gradient on millennial time scale based on the reconstruction of potential density (σθ) by combining data from dinoflagellate cyst assemblages and planktic foraminiferal (Neogloboquadrina pachyderma (s)) stable oxygen isotopes (δ18Oc). Following several calibration exercises, the likeliness of favorable seasonal preconditioning to open ocean convection is evaluated. The reconstructed σθ values reveal unfavorable conditions for vertical convection in the western Nordic Seas prior to ~7–6.5 ka B.P., with a westward increase and persistence of surface water buoyancy. Active overturning became more likely after 6.5 ka B.P. as suggested by a reduced and recurrently inverted vertical σθ gradient, while intermittent eastward spreading of lower density surface waters continued to modulate the area of potential overturning. Despite some reservation regarding the accuracy of the σθ values reconstructed, the documentation of relative changes of σθ gradients through time and space is suggested as a helpful tool for the appraisal of past overturning likeliness. |
format |
Article in Journal/Newspaper |
author |
Van Nieuwenhove, Nicolas Hillaire-Marcel, Claude Bauch, Henning A. de Vernal, Anne |
spellingShingle |
Van Nieuwenhove, Nicolas Hillaire-Marcel, Claude Bauch, Henning A. de Vernal, Anne Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies |
author_facet |
Van Nieuwenhove, Nicolas Hillaire-Marcel, Claude Bauch, Henning A. de Vernal, Anne |
author_sort |
Van Nieuwenhove, Nicolas |
title |
Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies |
title_short |
Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies |
title_full |
Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies |
title_fullStr |
Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies |
title_full_unstemmed |
Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies |
title_sort |
sea surface density gradients in the nordic seas during the holocene as revealed by paired microfossil and isotope proxies |
publisher |
AGU (American Geophysical Union) |
publishDate |
2016 |
url |
https://oceanrep.geomar.de/id/eprint/32941/ https://oceanrep.geomar.de/id/eprint/32941/1/palo20300.pdf https://doi.org/10.1002/2015PA002815 |
genre |
Neogloboquadrina pachyderma Nordic Seas |
genre_facet |
Neogloboquadrina pachyderma Nordic Seas |
op_relation |
https://oceanrep.geomar.de/id/eprint/32941/1/palo20300.pdf Van Nieuwenhove, N. , Hillaire-Marcel, C., Bauch, H. A. and de Vernal, A. (2016) Sea surface density gradients in the Nordic Seas during the Holocene as revealed by paired microfossil and isotope proxies. Paleoceanography, 31 (3). pp. 380-398. DOI 10.1002/2015PA002815 <https://doi.org/10.1002/2015PA002815>. doi:10.1002/2015PA002815 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1002/2015PA002815 |
container_title |
Paleoceanography |
container_volume |
31 |
container_issue |
3 |
container_start_page |
380 |
op_container_end_page |
398 |
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1766073060384833536 |