North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders
The Rockall Trough (RT) accommodates the warmest and saltiest branch of the North Atlantic Current, which delivers water from the Gulf Stream into the marine environment around western Europe. In addition, the European Slope Current (ESC) carries warm water northward along the eastern boundary of th...
Published in: | Journal of Geophysical Research: Oceans |
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Language: | English |
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Online Access: | http://nora.nerc.ac.uk/id/eprint/533747/ https://nora.nerc.ac.uk/id/eprint/533747/1/JGR%20Oceans%20-%202022%20-%20Fraser%20-%20North%20Atlantic%20Current%20and%20European%20Slope%20Current%20Circulation%20in%20the%20Rockall%20Trough%20Observed.pdf https://doi.org/10.1029/2022JC019291 |
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ftnerc:oai:nora.nerc.ac.uk:533747 2023-05-15T16:51:33+02:00 North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders Fraser, Neil J. Cunningham, Stuart A. Drysdale, Lewis A. Inall, Mark E. Johnson, Clare Jones, Sam C. Burmeister, Kristin Fox, Alan D. Dumont, Estelle Porter, Marie Holliday, N. Penny 2022-11-29 text http://nora.nerc.ac.uk/id/eprint/533747/ https://nora.nerc.ac.uk/id/eprint/533747/1/JGR%20Oceans%20-%202022%20-%20Fraser%20-%20North%20Atlantic%20Current%20and%20European%20Slope%20Current%20Circulation%20in%20the%20Rockall%20Trough%20Observed.pdf https://doi.org/10.1029/2022JC019291 en eng https://nora.nerc.ac.uk/id/eprint/533747/1/JGR%20Oceans%20-%202022%20-%20Fraser%20-%20North%20Atlantic%20Current%20and%20European%20Slope%20Current%20Circulation%20in%20the%20Rockall%20Trough%20Observed.pdf Fraser, Neil J.; Cunningham, Stuart A.; Drysdale, Lewis A.; Inall, Mark E.; Johnson, Clare; Jones, Sam C.; Burmeister, Kristin; Fox, Alan D.; Dumont, Estelle; Porter, Marie; Holliday, N. Penny orcid:0000-0002-9733-8002 . 2022 North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders. Journal of Geophysical Research: Oceans, 127 (12). https://doi.org/10.1029/2022JC019291 <https://doi.org/10.1029/2022JC019291> cc_by_4 CC-BY Publication - Article PeerReviewed 2022 ftnerc https://doi.org/10.1029/2022JC019291 2023-02-04T19:53:52Z The Rockall Trough (RT) accommodates the warmest and saltiest branch of the North Atlantic Current, which delivers water from the Gulf Stream into the marine environment around western Europe. In addition, the European Slope Current (ESC) carries warm water northward along the eastern boundary of the RT, and exchange between the ESC and the continental shelf is a dominant factor in determining the oceanographic conditions around the British Isles. However, the picture of the mean circulation and variability in the RT is still emerging, with a continuous observational campaign still in its relative infancy. The ESC, in particular, is poorly constrained by ship-based, mooring, and satellite observations. In this paper, we examine the RT circulation and volume transport using a temporally extended and spatially expanded observing network. Six years of continuous mooring occupation reveal that a large-amplitude, basin-scale freshening event, previously detected south of Iceland around 2015, impacted the RT around 2017. Geostrophic transport was greatly reduced during this period, driven by a concurrent subsurface temperature increase at the western boundary. The circulation regained strength during the latter part of the record. We gathered 110 glider transects over 22 months which capture the ESC velocity field in unprecedented detail. The data are sufficient to characterize both the mean state and the emergent seasonal variability of the ESC, and reveal the year-round presence of a southward countercurrent at depth. Variability in the strength and structure of this previously unstudied feature modulates net northward transport in the eastern boundary current system. Article in Journal/Newspaper Iceland north atlantic current North Atlantic Natural Environment Research Council: NERC Open Research Archive Rockall Trough ENVELOPE(-15.036,-15.036,53.825,53.825) Journal of Geophysical Research: Oceans 127 12 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
The Rockall Trough (RT) accommodates the warmest and saltiest branch of the North Atlantic Current, which delivers water from the Gulf Stream into the marine environment around western Europe. In addition, the European Slope Current (ESC) carries warm water northward along the eastern boundary of the RT, and exchange between the ESC and the continental shelf is a dominant factor in determining the oceanographic conditions around the British Isles. However, the picture of the mean circulation and variability in the RT is still emerging, with a continuous observational campaign still in its relative infancy. The ESC, in particular, is poorly constrained by ship-based, mooring, and satellite observations. In this paper, we examine the RT circulation and volume transport using a temporally extended and spatially expanded observing network. Six years of continuous mooring occupation reveal that a large-amplitude, basin-scale freshening event, previously detected south of Iceland around 2015, impacted the RT around 2017. Geostrophic transport was greatly reduced during this period, driven by a concurrent subsurface temperature increase at the western boundary. The circulation regained strength during the latter part of the record. We gathered 110 glider transects over 22 months which capture the ESC velocity field in unprecedented detail. The data are sufficient to characterize both the mean state and the emergent seasonal variability of the ESC, and reveal the year-round presence of a southward countercurrent at depth. Variability in the strength and structure of this previously unstudied feature modulates net northward transport in the eastern boundary current system. |
format |
Article in Journal/Newspaper |
author |
Fraser, Neil J. Cunningham, Stuart A. Drysdale, Lewis A. Inall, Mark E. Johnson, Clare Jones, Sam C. Burmeister, Kristin Fox, Alan D. Dumont, Estelle Porter, Marie Holliday, N. Penny |
spellingShingle |
Fraser, Neil J. Cunningham, Stuart A. Drysdale, Lewis A. Inall, Mark E. Johnson, Clare Jones, Sam C. Burmeister, Kristin Fox, Alan D. Dumont, Estelle Porter, Marie Holliday, N. Penny North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders |
author_facet |
Fraser, Neil J. Cunningham, Stuart A. Drysdale, Lewis A. Inall, Mark E. Johnson, Clare Jones, Sam C. Burmeister, Kristin Fox, Alan D. Dumont, Estelle Porter, Marie Holliday, N. Penny |
author_sort |
Fraser, Neil J. |
title |
North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders |
title_short |
North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders |
title_full |
North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders |
title_fullStr |
North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders |
title_full_unstemmed |
North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders |
title_sort |
north atlantic current and european slope current circulation in the rockall trough observed using moorings and gliders |
publishDate |
2022 |
url |
http://nora.nerc.ac.uk/id/eprint/533747/ https://nora.nerc.ac.uk/id/eprint/533747/1/JGR%20Oceans%20-%202022%20-%20Fraser%20-%20North%20Atlantic%20Current%20and%20European%20Slope%20Current%20Circulation%20in%20the%20Rockall%20Trough%20Observed.pdf https://doi.org/10.1029/2022JC019291 |
long_lat |
ENVELOPE(-15.036,-15.036,53.825,53.825) |
geographic |
Rockall Trough |
geographic_facet |
Rockall Trough |
genre |
Iceland north atlantic current North Atlantic |
genre_facet |
Iceland north atlantic current North Atlantic |
op_relation |
https://nora.nerc.ac.uk/id/eprint/533747/1/JGR%20Oceans%20-%202022%20-%20Fraser%20-%20North%20Atlantic%20Current%20and%20European%20Slope%20Current%20Circulation%20in%20the%20Rockall%20Trough%20Observed.pdf Fraser, Neil J.; Cunningham, Stuart A.; Drysdale, Lewis A.; Inall, Mark E.; Johnson, Clare; Jones, Sam C.; Burmeister, Kristin; Fox, Alan D.; Dumont, Estelle; Porter, Marie; Holliday, N. Penny orcid:0000-0002-9733-8002 . 2022 North Atlantic current and European slope current circulation in the Rockall Trough observed using moorings and gliders. Journal of Geophysical Research: Oceans, 127 (12). https://doi.org/10.1029/2022JC019291 <https://doi.org/10.1029/2022JC019291> |
op_rights |
cc_by_4 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1029/2022JC019291 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
127 |
container_issue |
12 |
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1766041667990716416 |