Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years
Eight time slices of surface-water paleoceanography were reconstructed from stable isotope and paleotemperature data to evaluate late Quaternary changes in density, current directions, and sea-ice cover in the Nordic Seas and NE Atlantic. We used isotopic records from 110 deep-sea cores, 20 of which...
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Format: | Article in Journal/Newspaper |
Language: | English |
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AGU (American Geophysical Union)
1995
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Online Access: | https://oceanrep.geomar.de/id/eprint/29460/ https://oceanrep.geomar.de/id/eprint/29460/1/Sarnthein.pdf https://doi.org/10.1029/95PA01453 |
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ftoceanrep:oai:oceanrep.geomar.de:29460 2023-05-15T16:41:29+02:00 Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years Sarnthein, Michael Jansen, Eystein Weinelt, Mara Arnold, Maurice Duplessy, Jean Claude Erlenkeuser, Helmut Flatøy, Astrid Johannessen, Gro Johannessen, Truls Jung, Simon Koc, Nalan Labeyrie, Laurent Maslin, Mark Pflaumann, Uwe Schulz, Hartmut 1995 text https://oceanrep.geomar.de/id/eprint/29460/ https://oceanrep.geomar.de/id/eprint/29460/1/Sarnthein.pdf https://doi.org/10.1029/95PA01453 en eng AGU (American Geophysical Union) https://oceanrep.geomar.de/id/eprint/29460/1/Sarnthein.pdf Sarnthein, M., Jansen, E., Weinelt, M., Arnold, M., Duplessy, J. C., Erlenkeuser, H., Flatøy, A., Johannessen, G., Johannessen, T., Jung, S., Koc, N., Labeyrie, L., Maslin, M., Pflaumann, U. and Schulz, H. (1995) Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years. Paleoceanography, 10 (6). pp. 1063-1094. DOI 10.1029/95PA01453 <https://doi.org/10.1029/95PA01453>. doi:10.1029/95PA01453 Article PeerReviewed 1995 ftoceanrep https://doi.org/10.1029/95PA01453 2023-04-07T15:20:25Z Eight time slices of surface-water paleoceanography were reconstructed from stable isotope and paleotemperature data to evaluate late Quaternary changes in density, current directions, and sea-ice cover in the Nordic Seas and NE Atlantic. We used isotopic records from 110 deep-sea cores, 20 of which are accelerator mass spectrometry (AMS)-14C dated and 30 of which have high (>8 cm /kyr) sedimentation rates, enabling a resolution of about 120 years. Paleotemperature estimates are based on species counts of planktonic foraminifera in 18 cores. The δ18O and δ13C distributions depict three main modes of surface circulation: (1) The Holocene-style interglacial mode which largely persisted over the last 12.8 14C ka, and probably during large parts of stage 3. (2) The peak glacial mode showing a cyclonic gyre in the, at least, seasonally ice-free Nordic Seas and a meltwater lens west of Ireland. Based on geostrophic forcing, it possibly turned clockwise, blocked the S-N flow across the eastern Iceland-Shetland ridge, and enhanced the Irminger current around west Iceland. It remains unclear whether surface-water density was sufficient for deepwater formation west of Norway. (3) A meltwater regime culminating during early glacial Termination I, when a great meltwater lens off northern Norway probably induced a clockwise circulation reaching south up to Faeroe, the northward inflow of Irminger Current water dominated the Icelandic Sea, and deepwater convection was stopped. In contrast to circulation modes two and three, the Holocene-style circulation mode appears most stable, even unaffected by major meltwater pools originating from the Scandinavian ice sheet, such as during δ18O event 3.1 and the Bölling. Meltwater phases markedly influenced the European continental climate by suppressing the “heat pump” of the Atlantic salinity conveyor belt. During the peak glacial, melting icebergs blocked the eastward advection of warm surface water toward Great Britain, thus accelerating buildup of the great European ice sheets; ... Article in Journal/Newspaper Ice Sheet Iceland Nordic Seas Northern Norway Planktonic foraminifera Sea ice OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Norway Paleoceanography 10 6 1063 1094 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Eight time slices of surface-water paleoceanography were reconstructed from stable isotope and paleotemperature data to evaluate late Quaternary changes in density, current directions, and sea-ice cover in the Nordic Seas and NE Atlantic. We used isotopic records from 110 deep-sea cores, 20 of which are accelerator mass spectrometry (AMS)-14C dated and 30 of which have high (>8 cm /kyr) sedimentation rates, enabling a resolution of about 120 years. Paleotemperature estimates are based on species counts of planktonic foraminifera in 18 cores. The δ18O and δ13C distributions depict three main modes of surface circulation: (1) The Holocene-style interglacial mode which largely persisted over the last 12.8 14C ka, and probably during large parts of stage 3. (2) The peak glacial mode showing a cyclonic gyre in the, at least, seasonally ice-free Nordic Seas and a meltwater lens west of Ireland. Based on geostrophic forcing, it possibly turned clockwise, blocked the S-N flow across the eastern Iceland-Shetland ridge, and enhanced the Irminger current around west Iceland. It remains unclear whether surface-water density was sufficient for deepwater formation west of Norway. (3) A meltwater regime culminating during early glacial Termination I, when a great meltwater lens off northern Norway probably induced a clockwise circulation reaching south up to Faeroe, the northward inflow of Irminger Current water dominated the Icelandic Sea, and deepwater convection was stopped. In contrast to circulation modes two and three, the Holocene-style circulation mode appears most stable, even unaffected by major meltwater pools originating from the Scandinavian ice sheet, such as during δ18O event 3.1 and the Bölling. Meltwater phases markedly influenced the European continental climate by suppressing the “heat pump” of the Atlantic salinity conveyor belt. During the peak glacial, melting icebergs blocked the eastward advection of warm surface water toward Great Britain, thus accelerating buildup of the great European ice sheets; ... |
format |
Article in Journal/Newspaper |
author |
Sarnthein, Michael Jansen, Eystein Weinelt, Mara Arnold, Maurice Duplessy, Jean Claude Erlenkeuser, Helmut Flatøy, Astrid Johannessen, Gro Johannessen, Truls Jung, Simon Koc, Nalan Labeyrie, Laurent Maslin, Mark Pflaumann, Uwe Schulz, Hartmut |
spellingShingle |
Sarnthein, Michael Jansen, Eystein Weinelt, Mara Arnold, Maurice Duplessy, Jean Claude Erlenkeuser, Helmut Flatøy, Astrid Johannessen, Gro Johannessen, Truls Jung, Simon Koc, Nalan Labeyrie, Laurent Maslin, Mark Pflaumann, Uwe Schulz, Hartmut Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years |
author_facet |
Sarnthein, Michael Jansen, Eystein Weinelt, Mara Arnold, Maurice Duplessy, Jean Claude Erlenkeuser, Helmut Flatøy, Astrid Johannessen, Gro Johannessen, Truls Jung, Simon Koc, Nalan Labeyrie, Laurent Maslin, Mark Pflaumann, Uwe Schulz, Hartmut |
author_sort |
Sarnthein, Michael |
title |
Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years |
title_short |
Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years |
title_full |
Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years |
title_fullStr |
Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years |
title_full_unstemmed |
Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years |
title_sort |
variations in atlantic surface ocean paleoceanography, 50°-80°n: a time-slice record of the last 30,000 years |
publisher |
AGU (American Geophysical Union) |
publishDate |
1995 |
url |
https://oceanrep.geomar.de/id/eprint/29460/ https://oceanrep.geomar.de/id/eprint/29460/1/Sarnthein.pdf https://doi.org/10.1029/95PA01453 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Ice Sheet Iceland Nordic Seas Northern Norway Planktonic foraminifera Sea ice |
genre_facet |
Ice Sheet Iceland Nordic Seas Northern Norway Planktonic foraminifera Sea ice |
op_relation |
https://oceanrep.geomar.de/id/eprint/29460/1/Sarnthein.pdf Sarnthein, M., Jansen, E., Weinelt, M., Arnold, M., Duplessy, J. C., Erlenkeuser, H., Flatøy, A., Johannessen, G., Johannessen, T., Jung, S., Koc, N., Labeyrie, L., Maslin, M., Pflaumann, U. and Schulz, H. (1995) Variations in Atlantic surface ocean paleoceanography, 50°-80°N: A time-slice record of the last 30,000 years. Paleoceanography, 10 (6). pp. 1063-1094. DOI 10.1029/95PA01453 <https://doi.org/10.1029/95PA01453>. doi:10.1029/95PA01453 |
op_doi |
https://doi.org/10.1029/95PA01453 |
container_title |
Paleoceanography |
container_volume |
10 |
container_issue |
6 |
container_start_page |
1063 |
op_container_end_page |
1094 |
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1766031925844115456 |