Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic
The Extended Ellett Line (EEL) hydrographic section extends from Scotland to Iceland crossing the Rockall Trough, Hatton-Rockall Basin and Iceland Basin. With 61 full-depth stations at a horizontal resolution of 10 to 50 km, the EEL samples the upper limb of the Atlantic Meridional Overturning Circu...
Published in: | Journal of Geophysical Research: Oceans |
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Online Access: | https://eprints.soton.ac.uk/380440/ https://eprints.soton.ac.uk/380440/1/jgrc21365.pdf https://eprints.soton.ac.uk/380440/2/Holliday_et_al-2015-Journal_of_Geophysical_Research__Oceans.pdf |
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ftsouthampton:oai:eprints.soton.ac.uk:380440 2023-07-30T04:04:19+02:00 Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic Holliday, N.P. Cunningham, S.A. Johnson, C. Gary, S.F. Griffiths, C. Read, J.F. Sherwin, T. 2015-09 text https://eprints.soton.ac.uk/380440/ https://eprints.soton.ac.uk/380440/1/jgrc21365.pdf https://eprints.soton.ac.uk/380440/2/Holliday_et_al-2015-Journal_of_Geophysical_Research__Oceans.pdf en English eng https://eprints.soton.ac.uk/380440/1/jgrc21365.pdf https://eprints.soton.ac.uk/380440/2/Holliday_et_al-2015-Journal_of_Geophysical_Research__Oceans.pdf Holliday, N.P., Cunningham, S.A., Johnson, C., Gary, S.F., Griffiths, C., Read, J.F. and Sherwin, T. (2015) Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic. Journal of Geophysical Research: Oceans, 120 (9), 5945-5967. (doi:10.1002/2015JC010762 <http://dx.doi.org/10.1002/2015JC010762>). cc_by_4 Article PeerReviewed 2015 ftsouthampton https://doi.org/10.1002/2015JC010762 2023-07-09T22:01:00Z The Extended Ellett Line (EEL) hydrographic section extends from Scotland to Iceland crossing the Rockall Trough, Hatton-Rockall Basin and Iceland Basin. With 61 full-depth stations at a horizontal resolution of 10 to 50 km, the EEL samples the upper limb of the Atlantic Meridional Overturning Circulation flowing across the Iceland-Scotland Ridge into the Nordic Seas. The Rockall Trough has been sampled nearly four times per year from 1975 to 1996, and the full section annually since 1996. The EEL is an exceptionally long timeseries of deep-ocean temperatures and salinities. This study extends prior work in the Rockall Trough, and examines for the first time 18 year records in the Iceland and Hatton-Rockall Basins. We quantify errors in the timeseries from two sources: observational errors and aliasing. The data quality and annual sampling are suitable for observing interannual to decadal variability because the variability exceeds our error estimates. The upper waters of all 3 basins are cooler/fresher from 1997 to 2001, warmer/more saline 2001 to 2006, and cooler/fresher from 2006 to 2014. A reference level for geostrophic shear is developed heuristically and by comparison with sea-surface altimetry. The mean northward transport in the upper waters is 6.7±3.7 Sv and there is a 6.1±2.5 Sv southward flow below the thermocline. Although the magnitude of the Iceland Basin overturning circulation (4.3±1.9 Sv) is greater than in the Rockall Trough (3.0±3.7 Sv), the variability is greater in the Rockall Trough. We discuss the results in the context of our understanding of drivers of variability. Article in Journal/Newspaper Iceland Nordic Seas North Atlantic University of Southampton: e-Prints Soton Hatton-Rockall Basin ENVELOPE(-17.000,-17.000,57.500,57.500) Rockall Trough ENVELOPE(-15.036,-15.036,53.825,53.825) Journal of Geophysical Research: Oceans 120 9 5945 5967 |
institution |
Open Polar |
collection |
University of Southampton: e-Prints Soton |
op_collection_id |
ftsouthampton |
language |
English |
description |
The Extended Ellett Line (EEL) hydrographic section extends from Scotland to Iceland crossing the Rockall Trough, Hatton-Rockall Basin and Iceland Basin. With 61 full-depth stations at a horizontal resolution of 10 to 50 km, the EEL samples the upper limb of the Atlantic Meridional Overturning Circulation flowing across the Iceland-Scotland Ridge into the Nordic Seas. The Rockall Trough has been sampled nearly four times per year from 1975 to 1996, and the full section annually since 1996. The EEL is an exceptionally long timeseries of deep-ocean temperatures and salinities. This study extends prior work in the Rockall Trough, and examines for the first time 18 year records in the Iceland and Hatton-Rockall Basins. We quantify errors in the timeseries from two sources: observational errors and aliasing. The data quality and annual sampling are suitable for observing interannual to decadal variability because the variability exceeds our error estimates. The upper waters of all 3 basins are cooler/fresher from 1997 to 2001, warmer/more saline 2001 to 2006, and cooler/fresher from 2006 to 2014. A reference level for geostrophic shear is developed heuristically and by comparison with sea-surface altimetry. The mean northward transport in the upper waters is 6.7±3.7 Sv and there is a 6.1±2.5 Sv southward flow below the thermocline. Although the magnitude of the Iceland Basin overturning circulation (4.3±1.9 Sv) is greater than in the Rockall Trough (3.0±3.7 Sv), the variability is greater in the Rockall Trough. We discuss the results in the context of our understanding of drivers of variability. |
format |
Article in Journal/Newspaper |
author |
Holliday, N.P. Cunningham, S.A. Johnson, C. Gary, S.F. Griffiths, C. Read, J.F. Sherwin, T. |
spellingShingle |
Holliday, N.P. Cunningham, S.A. Johnson, C. Gary, S.F. Griffiths, C. Read, J.F. Sherwin, T. Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic |
author_facet |
Holliday, N.P. Cunningham, S.A. Johnson, C. Gary, S.F. Griffiths, C. Read, J.F. Sherwin, T. |
author_sort |
Holliday, N.P. |
title |
Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic |
title_short |
Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic |
title_full |
Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic |
title_fullStr |
Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic |
title_full_unstemmed |
Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic |
title_sort |
multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar north atlantic |
publishDate |
2015 |
url |
https://eprints.soton.ac.uk/380440/ https://eprints.soton.ac.uk/380440/1/jgrc21365.pdf https://eprints.soton.ac.uk/380440/2/Holliday_et_al-2015-Journal_of_Geophysical_Research__Oceans.pdf |
long_lat |
ENVELOPE(-17.000,-17.000,57.500,57.500) ENVELOPE(-15.036,-15.036,53.825,53.825) |
geographic |
Hatton-Rockall Basin Rockall Trough |
geographic_facet |
Hatton-Rockall Basin Rockall Trough |
genre |
Iceland Nordic Seas North Atlantic |
genre_facet |
Iceland Nordic Seas North Atlantic |
op_relation |
https://eprints.soton.ac.uk/380440/1/jgrc21365.pdf https://eprints.soton.ac.uk/380440/2/Holliday_et_al-2015-Journal_of_Geophysical_Research__Oceans.pdf Holliday, N.P., Cunningham, S.A., Johnson, C., Gary, S.F., Griffiths, C., Read, J.F. and Sherwin, T. (2015) Multidecadal variability of potential temperature, salinity, and transport in the eastern subpolar North Atlantic. Journal of Geophysical Research: Oceans, 120 (9), 5945-5967. (doi:10.1002/2015JC010762 <http://dx.doi.org/10.1002/2015JC010762>). |
op_rights |
cc_by_4 |
op_doi |
https://doi.org/10.1002/2015JC010762 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
120 |
container_issue |
9 |
container_start_page |
5945 |
op_container_end_page |
5967 |
_version_ |
1772815664872947712 |