Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water
Iceland-Scotland Overflow Water (ISOW) and Labrador Seawater (LSW) are major water masses of the lower Atlantic Meridional Overturning Circulation (AMOC). Therefore, the investigation of their transport pathways is important to understand the structure of the AMOC and how climate properties are expo...
Published in: | Frontiers in Marine Science |
---|---|
Main Authors: | , , , |
Other Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
Frontiers Media SA
2022
|
Subjects: | |
Online Access: | http://dx.doi.org/10.3389/fmars.2022.897729 https://www.frontiersin.org/articles/10.3389/fmars.2022.897729/full |
id |
crfrontiers:10.3389/fmars.2022.897729 |
---|---|
record_format |
openpolar |
spelling |
crfrontiers:10.3389/fmars.2022.897729 2024-09-30T14:36:00+00:00 Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water Castrillejo, Maxi Casacuberta, Núria Vockenhuber, Christof Lherminier, Pascale Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung ETH Zürich Foundation European Research Council Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung 2022 http://dx.doi.org/10.3389/fmars.2022.897729 https://www.frontiersin.org/articles/10.3389/fmars.2022.897729/full unknown Frontiers Media SA https://creativecommons.org/licenses/by/4.0/ Frontiers in Marine Science volume 9 ISSN 2296-7745 journal-article 2022 crfrontiers https://doi.org/10.3389/fmars.2022.897729 2024-09-17T04:13:27Z Iceland-Scotland Overflow Water (ISOW) and Labrador Seawater (LSW) are major water masses of the lower Atlantic Meridional Overturning Circulation (AMOC). Therefore, the investigation of their transport pathways is important to understand the structure of the AMOC and how climate properties are exported from the North Atlantic to lower latitudes. There is growing evidence from Lagrangian model simulations and observations that ISOW and LSW detach from boundary currents and spread off-boundary, into the basin interior in the Atlantic Ocean. Nuclear fuel reprocessing facilities of Sellafield and La Hague have been releasing artificial iodine ( 129 I) into the northeastern Atlantic since the 1960ies. As a result, 129 I is supplied from north of the Greenland-Scotland passages into the subpolar region labelling waters of the southward flowing lower AMOC. To explore the potential of 129 I as tracer of boundary and interior ISOW and LSW transport pathways, we analyzed the tracer concentrations in seawater collected during four oceanographic cruises in the subpolar and subtropical North Atlantic regions between 2017 and 2019. The new tracer observations showed that deep tracer maxima highlighted the spreading of ISOW along the flanks of Reykjanes Ridge, across fracture zones and into the eastern subpolar North Atlantic supporting recent Lagrangian studies. Further, we found that 129 I is intruding the Atlantic Ocean at unprecedented rate and labelling much larger extensions and water masses than in the recent past. This has enabled the use of 129 I for other purposes aside from tracing ISOW. For example, increasing tracer levels allowed us to differentiate between newly formed 129 I-rich LSW and older vintages poorer in 129 I content. Further, 129 I concentration maxima at intermediate depths could be used to track the spreading of LSW beyond the subpolar region and far into subtropical seas near Bermuda. Considering that 129 I releases from Sellafield and La Hague have increased or levelled off during the last ... Article in Journal/Newspaper Greenland Iceland Labrador Sea North Atlantic Frontiers (Publisher) Greenland Reykjanes ENVELOPE(-22.250,-22.250,65.467,65.467) Frontiers in Marine Science 9 |
institution |
Open Polar |
collection |
Frontiers (Publisher) |
op_collection_id |
crfrontiers |
language |
unknown |
description |
Iceland-Scotland Overflow Water (ISOW) and Labrador Seawater (LSW) are major water masses of the lower Atlantic Meridional Overturning Circulation (AMOC). Therefore, the investigation of their transport pathways is important to understand the structure of the AMOC and how climate properties are exported from the North Atlantic to lower latitudes. There is growing evidence from Lagrangian model simulations and observations that ISOW and LSW detach from boundary currents and spread off-boundary, into the basin interior in the Atlantic Ocean. Nuclear fuel reprocessing facilities of Sellafield and La Hague have been releasing artificial iodine ( 129 I) into the northeastern Atlantic since the 1960ies. As a result, 129 I is supplied from north of the Greenland-Scotland passages into the subpolar region labelling waters of the southward flowing lower AMOC. To explore the potential of 129 I as tracer of boundary and interior ISOW and LSW transport pathways, we analyzed the tracer concentrations in seawater collected during four oceanographic cruises in the subpolar and subtropical North Atlantic regions between 2017 and 2019. The new tracer observations showed that deep tracer maxima highlighted the spreading of ISOW along the flanks of Reykjanes Ridge, across fracture zones and into the eastern subpolar North Atlantic supporting recent Lagrangian studies. Further, we found that 129 I is intruding the Atlantic Ocean at unprecedented rate and labelling much larger extensions and water masses than in the recent past. This has enabled the use of 129 I for other purposes aside from tracing ISOW. For example, increasing tracer levels allowed us to differentiate between newly formed 129 I-rich LSW and older vintages poorer in 129 I content. Further, 129 I concentration maxima at intermediate depths could be used to track the spreading of LSW beyond the subpolar region and far into subtropical seas near Bermuda. Considering that 129 I releases from Sellafield and La Hague have increased or levelled off during the last ... |
author2 |
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung ETH Zürich Foundation European Research Council Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung |
format |
Article in Journal/Newspaper |
author |
Castrillejo, Maxi Casacuberta, Núria Vockenhuber, Christof Lherminier, Pascale |
spellingShingle |
Castrillejo, Maxi Casacuberta, Núria Vockenhuber, Christof Lherminier, Pascale Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water |
author_facet |
Castrillejo, Maxi Casacuberta, Núria Vockenhuber, Christof Lherminier, Pascale |
author_sort |
Castrillejo, Maxi |
title |
Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water |
title_short |
Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water |
title_full |
Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water |
title_fullStr |
Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water |
title_full_unstemmed |
Rapidly Increasing Artificial Iodine Highlights Pathways of Iceland-Scotland Overflow Water and Labrador Sea Water |
title_sort |
rapidly increasing artificial iodine highlights pathways of iceland-scotland overflow water and labrador sea water |
publisher |
Frontiers Media SA |
publishDate |
2022 |
url |
http://dx.doi.org/10.3389/fmars.2022.897729 https://www.frontiersin.org/articles/10.3389/fmars.2022.897729/full |
long_lat |
ENVELOPE(-22.250,-22.250,65.467,65.467) |
geographic |
Greenland Reykjanes |
geographic_facet |
Greenland Reykjanes |
genre |
Greenland Iceland Labrador Sea North Atlantic |
genre_facet |
Greenland Iceland Labrador Sea North Atlantic |
op_source |
Frontiers in Marine Science volume 9 ISSN 2296-7745 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3389/fmars.2022.897729 |
container_title |
Frontiers in Marine Science |
container_volume |
9 |
_version_ |
1811639190576693248 |