Possible predictability in overflow from the Denmark Strait
The overflow and descent of cold dense water from the Denmark Strait sill-a submarine passage between Greenland and Iceland-is a principal means by which the deep ocean is ventilated, and is an important element in the global thermohaline circulation. Previous investigations of its variability-in pa...
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Online Access: | https://oceanrep.geomar.de/id/eprint/1092/ https://oceanrep.geomar.de/id/eprint/1092/1/397243a0.pdf https://doi.org/10.1038/16680 |
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ftoceanrep:oai:oceanrep.geomar.de:1092 2024-09-30T14:34:05+00:00 Possible predictability in overflow from the Denmark Strait Dickson, B. Meincke, Jens Vassle, I. Jungclaus, J. Osterhus, S. 1999 text https://oceanrep.geomar.de/id/eprint/1092/ https://oceanrep.geomar.de/id/eprint/1092/1/397243a0.pdf https://doi.org/10.1038/16680 en eng Nature Publishing Group https://oceanrep.geomar.de/id/eprint/1092/1/397243a0.pdf Dickson, B., Meincke, J., Vassle, I., Jungclaus, J. and Osterhus, S. (1999) Possible predictability in overflow from the Denmark Strait. Nature, 397 . pp. 243-246. DOI 10.1038/16680 <https://doi.org/10.1038/16680>. doi:10.1038/16680 info:eu-repo/semantics/restrictedAccess Article PeerReviewed 1999 ftoceanrep https://doi.org/10.1038/16680 2024-09-04T05:04:40Z The overflow and descent of cold dense water from the Denmark Strait sill-a submarine passage between Greenland and Iceland-is a principal means by which the deep ocean is ventilated, and is an important element in the global thermohaline circulation. Previous investigations of its variability-in particular, direct current measurements(1,2) in the overflow core since 1986-have shown surprisingly little evidence of long-term changes in now speed. Here we report significant changes in the overflow characteristics during the winter of 1996-97, measured using two current-meter moorings and an inverted echo sounder located at different depths in the fastest part of the now. The overflow warmed to the highest monthly value yet recorded (2.4 degrees C), and showed a pronounced slowing and thinning at its lower margin. We believe that the extreme warmth of the overflow caused it to run higher on the continental slope off east Greenland, so that the lower current meters and the echo sounder were temporarily outside and deeper than the fast-flowing core; model simulations appear to confirm this interpretation, We suggest that the extreme warmth of the overflow is a lagged response to a warming upstream in the Fram Strait three years earlier (caused by an exceptional amplification of the winter North Atlantic Oscillation). If this is so, over-now characteristics may be predictable. Article in Journal/Newspaper Denmark Strait East Greenland Fram Strait Greenland Iceland North Atlantic North Atlantic oscillation OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Greenland Nature 397 6716 243 246 |
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OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
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language |
English |
description |
The overflow and descent of cold dense water from the Denmark Strait sill-a submarine passage between Greenland and Iceland-is a principal means by which the deep ocean is ventilated, and is an important element in the global thermohaline circulation. Previous investigations of its variability-in particular, direct current measurements(1,2) in the overflow core since 1986-have shown surprisingly little evidence of long-term changes in now speed. Here we report significant changes in the overflow characteristics during the winter of 1996-97, measured using two current-meter moorings and an inverted echo sounder located at different depths in the fastest part of the now. The overflow warmed to the highest monthly value yet recorded (2.4 degrees C), and showed a pronounced slowing and thinning at its lower margin. We believe that the extreme warmth of the overflow caused it to run higher on the continental slope off east Greenland, so that the lower current meters and the echo sounder were temporarily outside and deeper than the fast-flowing core; model simulations appear to confirm this interpretation, We suggest that the extreme warmth of the overflow is a lagged response to a warming upstream in the Fram Strait three years earlier (caused by an exceptional amplification of the winter North Atlantic Oscillation). If this is so, over-now characteristics may be predictable. |
format |
Article in Journal/Newspaper |
author |
Dickson, B. Meincke, Jens Vassle, I. Jungclaus, J. Osterhus, S. |
spellingShingle |
Dickson, B. Meincke, Jens Vassle, I. Jungclaus, J. Osterhus, S. Possible predictability in overflow from the Denmark Strait |
author_facet |
Dickson, B. Meincke, Jens Vassle, I. Jungclaus, J. Osterhus, S. |
author_sort |
Dickson, B. |
title |
Possible predictability in overflow from the Denmark Strait |
title_short |
Possible predictability in overflow from the Denmark Strait |
title_full |
Possible predictability in overflow from the Denmark Strait |
title_fullStr |
Possible predictability in overflow from the Denmark Strait |
title_full_unstemmed |
Possible predictability in overflow from the Denmark Strait |
title_sort |
possible predictability in overflow from the denmark strait |
publisher |
Nature Publishing Group |
publishDate |
1999 |
url |
https://oceanrep.geomar.de/id/eprint/1092/ https://oceanrep.geomar.de/id/eprint/1092/1/397243a0.pdf https://doi.org/10.1038/16680 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Denmark Strait East Greenland Fram Strait Greenland Iceland North Atlantic North Atlantic oscillation |
genre_facet |
Denmark Strait East Greenland Fram Strait Greenland Iceland North Atlantic North Atlantic oscillation |
op_relation |
https://oceanrep.geomar.de/id/eprint/1092/1/397243a0.pdf Dickson, B., Meincke, J., Vassle, I., Jungclaus, J. and Osterhus, S. (1999) Possible predictability in overflow from the Denmark Strait. Nature, 397 . pp. 243-246. DOI 10.1038/16680 <https://doi.org/10.1038/16680>. doi:10.1038/16680 |
op_rights |
info:eu-repo/semantics/restrictedAccess |
op_doi |
https://doi.org/10.1038/16680 |
container_title |
Nature |
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397 |
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6716 |
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243 |
op_container_end_page |
246 |
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1811637793735049216 |