Recent upper layer cooling and freshening in the Norwegian Sea
Several time series of temperature and salinity in the Norwegian Sea indicate a general upper layer decrease in both variables. The observations indicate that this change began in about the middle of the 1960s. Time series at Ocean Weather Station "M" (OWS"M"), from Russian surve...
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ftimr:oai:imr.brage.unit.no:11250/105548 2023-05-15T14:51:55+02:00 Recent upper layer cooling and freshening in the Norwegian Sea Blindheim, Johan Østerhus, Svein Borovkov, Vladimir Hansen, Bogi Malmberg, Svend-Aage Turrell, William R. 1996 application/pdf http://hdl.handle.net/11250/105548 eng eng ICES ICES CM Documents;1996/C:7 This report is not to be cited without prior reference to the authors http://hdl.handle.net/11250/105548 12 s. hydrography hydrografi current measurements strømmålinger VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 Working paper 1996 ftimr 2021-09-23T20:14:49Z Several time series of temperature and salinity in the Norwegian Sea indicate a general upper layer decrease in both variables. The observations indicate that this change began in about the middle of the 1960s. Time series at Ocean Weather Station "M" (OWS"M"), from Russian surveys in the southem Norwegian Sea as well as Scottish and Faroese observations in the Faroe-Shetland Channel and around the Faroes, all have similar trends and show that this is a phenomenon which affects wide areas in the Norwegian Sea. The reason for this trend is an increased supply of freshwater in the East Icelandic Current. As a result, both temperature and salinity is now at a lower level than during the "Great Salinity Anomaly'' ("GSA") in the 1970s both at 400 m depth at OWS "M" and in the 200- 500 m layer in the southem Norwegian Sea as observed in the Russian time series. The forcing may be increased production of Arctic surface water in the Greenland Sea when the deep convection is reduced, or more probably, increased export of freshwater from the Arctic Ocean. There is fairly good correlation between the wind stress curl over the Greenland Sea and the Russian time series of temperature and salinity, averaged between 200 and 500 m depth and between O and 3.5°E along 63°N in the Norwegian Sea. Considerably increased supply of Arctic Water from the East Icelandic Current during a period around 1978, clearly reinforced the "GSA" in the Nordic Seas. This also explains the coinciding variation in Atlantic and Arctic waters in the Faroe-Shetland Channel during the "GSA". Report Arctic Arctic Ocean Faroes Greenland Greenland Sea Nordic Seas Norwegian Sea Institute for Marine Research: Brage IMR Arctic Arctic Ocean Norwegian Sea Greenland Curl ENVELOPE(-63.071,-63.071,-70.797,-70.797) |
institution |
Open Polar |
collection |
Institute for Marine Research: Brage IMR |
op_collection_id |
ftimr |
language |
English |
topic |
hydrography hydrografi current measurements strømmålinger VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 |
spellingShingle |
hydrography hydrografi current measurements strømmålinger VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 Blindheim, Johan Østerhus, Svein Borovkov, Vladimir Hansen, Bogi Malmberg, Svend-Aage Turrell, William R. Recent upper layer cooling and freshening in the Norwegian Sea |
topic_facet |
hydrography hydrografi current measurements strømmålinger VDP::Mathematics and natural science: 400::Zoology and botany: 480::Marine biology: 497 VDP::Mathematics and natural science: 400::Geosciences: 450::Oceanography: 452 |
description |
Several time series of temperature and salinity in the Norwegian Sea indicate a general upper layer decrease in both variables. The observations indicate that this change began in about the middle of the 1960s. Time series at Ocean Weather Station "M" (OWS"M"), from Russian surveys in the southem Norwegian Sea as well as Scottish and Faroese observations in the Faroe-Shetland Channel and around the Faroes, all have similar trends and show that this is a phenomenon which affects wide areas in the Norwegian Sea. The reason for this trend is an increased supply of freshwater in the East Icelandic Current. As a result, both temperature and salinity is now at a lower level than during the "Great Salinity Anomaly'' ("GSA") in the 1970s both at 400 m depth at OWS "M" and in the 200- 500 m layer in the southem Norwegian Sea as observed in the Russian time series. The forcing may be increased production of Arctic surface water in the Greenland Sea when the deep convection is reduced, or more probably, increased export of freshwater from the Arctic Ocean. There is fairly good correlation between the wind stress curl over the Greenland Sea and the Russian time series of temperature and salinity, averaged between 200 and 500 m depth and between O and 3.5°E along 63°N in the Norwegian Sea. Considerably increased supply of Arctic Water from the East Icelandic Current during a period around 1978, clearly reinforced the "GSA" in the Nordic Seas. This also explains the coinciding variation in Atlantic and Arctic waters in the Faroe-Shetland Channel during the "GSA". |
format |
Report |
author |
Blindheim, Johan Østerhus, Svein Borovkov, Vladimir Hansen, Bogi Malmberg, Svend-Aage Turrell, William R. |
author_facet |
Blindheim, Johan Østerhus, Svein Borovkov, Vladimir Hansen, Bogi Malmberg, Svend-Aage Turrell, William R. |
author_sort |
Blindheim, Johan |
title |
Recent upper layer cooling and freshening in the Norwegian Sea |
title_short |
Recent upper layer cooling and freshening in the Norwegian Sea |
title_full |
Recent upper layer cooling and freshening in the Norwegian Sea |
title_fullStr |
Recent upper layer cooling and freshening in the Norwegian Sea |
title_full_unstemmed |
Recent upper layer cooling and freshening in the Norwegian Sea |
title_sort |
recent upper layer cooling and freshening in the norwegian sea |
publisher |
ICES |
publishDate |
1996 |
url |
http://hdl.handle.net/11250/105548 |
long_lat |
ENVELOPE(-63.071,-63.071,-70.797,-70.797) |
geographic |
Arctic Arctic Ocean Norwegian Sea Greenland Curl |
geographic_facet |
Arctic Arctic Ocean Norwegian Sea Greenland Curl |
genre |
Arctic Arctic Ocean Faroes Greenland Greenland Sea Nordic Seas Norwegian Sea |
genre_facet |
Arctic Arctic Ocean Faroes Greenland Greenland Sea Nordic Seas Norwegian Sea |
op_source |
12 s. |
op_relation |
ICES CM Documents;1996/C:7 This report is not to be cited without prior reference to the authors http://hdl.handle.net/11250/105548 |
_version_ |
1766323060595490816 |