The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations
The inflow of warm and saline Atlantic water to the Arctic Mediterranean (Nordic Seas and Arctic Ocean) between Iceland and the Faroes (IF inflow) is the strongest Atlantic inflow branch in terms of volume transport and is associated with a large transport of heat towards the Arctic. The IF inflow i...
Published in: | Ocean Science |
---|---|
Main Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2023
|
Subjects: | |
Online Access: | https://hdl.handle.net/11250/3137612 https://doi.org/10.5194/os-19-1225-2023 |
id |
ftnorce:oai:norceresearch.brage.unit.no:11250/3137612 |
---|---|
record_format |
openpolar |
spelling |
ftnorce:oai:norceresearch.brage.unit.no:11250/3137612 2024-09-15T17:54:19+00:00 The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations Hansen, Bogi Larsen, Karin Margretha Húsgarð Hátún, Egil Hjálmar Olsen, Steffen M. Gierisch, Andrea M. U. Østerhus, Svein Ólafsdóttir, Sædis 2023 application/pdf https://hdl.handle.net/11250/3137612 https://doi.org/10.5194/os-19-1225-2023 eng eng EC/H2020/727852 Ocean Science. 2023, 19 (4), 1225-1252. urn:issn:1812-0784 https://hdl.handle.net/11250/3137612 https://doi.org/10.5194/os-19-1225-2023 cristin:2177929 Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no © Author(s) 2023 Ocean Science 19 4 1225-1252 Peer reviewed Journal article 2023 ftnorce https://doi.org/10.5194/os-19-1225-2023 2024-07-07T23:32:14Z The inflow of warm and saline Atlantic water to the Arctic Mediterranean (Nordic Seas and Arctic Ocean) between Iceland and the Faroes (IF inflow) is the strongest Atlantic inflow branch in terms of volume transport and is associated with a large transport of heat towards the Arctic. The IF inflow is monitored in a section east of the Iceland–Faroe Ridge (IFR) by use of sea level anomaly (SLA) data from satellite altimetry, a method that has been calibrated by in situ observations gathered over 2 decades. Monthly averaged surface velocity anomalies calculated from SLA data were strongly correlated with anomalies measured by moored acoustic Doppler current profilers (ADCPs) with consistently higher correlations when using the reprocessed SLA data released in December 2021 rather than the earlier version. In contrast to the earlier version, the reprocessed data also had the correct conversion factor between sea level slope and surface velocity required by geostrophy. Our results show that the IF inflow crosses the IFR in two separate branches. The Icelandic branch is a jet over the Icelandic slope with average surface speed exceeding 20 cm s−1, but it is narrow and shallow with an average volume transport of less than 1 Sv (106 m3 s−1). Most of the Atlantic water crosses the IFR close to its southernmost end in the Faroese branch. Between these two branches, water from the Icelandic branch turns back onto the ridge in a retroflection with a recirculation over the northernmost bank on the IFR. Combining multi-sensor in situ observations with satellite SLA data, monthly mean volume transport of the IF inflow has been determined from January 1993 to December 2021. The IF inflow is part of the Atlantic Meridional Overturning Circulation (AMOC), which is expected to weaken under continued global warming. Our results show no weakening of the IF inflow. Annually averaged volume transport of Atlantic water through the monitoring section had a statistically significant (95 % confidence level) increasing trend of ... Article in Journal/Newspaper Arctic Ocean Faroes Global warming Iceland Nordic Seas NORCE vitenarkiv (Norwegian Research Centre) Ocean Science 19 4 1225 1252 |
institution |
Open Polar |
collection |
NORCE vitenarkiv (Norwegian Research Centre) |
op_collection_id |
ftnorce |
language |
English |
description |
The inflow of warm and saline Atlantic water to the Arctic Mediterranean (Nordic Seas and Arctic Ocean) between Iceland and the Faroes (IF inflow) is the strongest Atlantic inflow branch in terms of volume transport and is associated with a large transport of heat towards the Arctic. The IF inflow is monitored in a section east of the Iceland–Faroe Ridge (IFR) by use of sea level anomaly (SLA) data from satellite altimetry, a method that has been calibrated by in situ observations gathered over 2 decades. Monthly averaged surface velocity anomalies calculated from SLA data were strongly correlated with anomalies measured by moored acoustic Doppler current profilers (ADCPs) with consistently higher correlations when using the reprocessed SLA data released in December 2021 rather than the earlier version. In contrast to the earlier version, the reprocessed data also had the correct conversion factor between sea level slope and surface velocity required by geostrophy. Our results show that the IF inflow crosses the IFR in two separate branches. The Icelandic branch is a jet over the Icelandic slope with average surface speed exceeding 20 cm s−1, but it is narrow and shallow with an average volume transport of less than 1 Sv (106 m3 s−1). Most of the Atlantic water crosses the IFR close to its southernmost end in the Faroese branch. Between these two branches, water from the Icelandic branch turns back onto the ridge in a retroflection with a recirculation over the northernmost bank on the IFR. Combining multi-sensor in situ observations with satellite SLA data, monthly mean volume transport of the IF inflow has been determined from January 1993 to December 2021. The IF inflow is part of the Atlantic Meridional Overturning Circulation (AMOC), which is expected to weaken under continued global warming. Our results show no weakening of the IF inflow. Annually averaged volume transport of Atlantic water through the monitoring section had a statistically significant (95 % confidence level) increasing trend of ... |
format |
Article in Journal/Newspaper |
author |
Hansen, Bogi Larsen, Karin Margretha Húsgarð Hátún, Egil Hjálmar Olsen, Steffen M. Gierisch, Andrea M. U. Østerhus, Svein Ólafsdóttir, Sædis |
spellingShingle |
Hansen, Bogi Larsen, Karin Margretha Húsgarð Hátún, Egil Hjálmar Olsen, Steffen M. Gierisch, Andrea M. U. Østerhus, Svein Ólafsdóttir, Sædis The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations |
author_facet |
Hansen, Bogi Larsen, Karin Margretha Húsgarð Hátún, Egil Hjálmar Olsen, Steffen M. Gierisch, Andrea M. U. Østerhus, Svein Ólafsdóttir, Sædis |
author_sort |
Hansen, Bogi |
title |
The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations |
title_short |
The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations |
title_full |
The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations |
title_fullStr |
The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations |
title_full_unstemmed |
The Iceland-Faroe warm-water flow towards the Arctic estimated from satellite altimetry and in situ observations |
title_sort |
iceland-faroe warm-water flow towards the arctic estimated from satellite altimetry and in situ observations |
publishDate |
2023 |
url |
https://hdl.handle.net/11250/3137612 https://doi.org/10.5194/os-19-1225-2023 |
genre |
Arctic Ocean Faroes Global warming Iceland Nordic Seas |
genre_facet |
Arctic Ocean Faroes Global warming Iceland Nordic Seas |
op_source |
Ocean Science 19 4 1225-1252 |
op_relation |
EC/H2020/727852 Ocean Science. 2023, 19 (4), 1225-1252. urn:issn:1812-0784 https://hdl.handle.net/11250/3137612 https://doi.org/10.5194/os-19-1225-2023 cristin:2177929 |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no © Author(s) 2023 |
op_doi |
https://doi.org/10.5194/os-19-1225-2023 |
container_title |
Ocean Science |
container_volume |
19 |
container_issue |
4 |
container_start_page |
1225 |
op_container_end_page |
1252 |
_version_ |
1810430599289110528 |