Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard
Kongsfjorden and the West Spitsbergen Shelf is a region whose seasonal hydrography is dominated by the balance of Atlantic Water, Arctic waters, and glacial melt. Regional seasonality and the cross-shelf exchange processes have been investigated using conductivity-temperature-depth (CTD) observation...
Published in: | Journal of Geophysical Research |
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Language: | English |
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American Geophysical Union
2005
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Online Access: | https://hdl.handle.net/1956/855 https://doi.org/10.1029/2004jc002757 |
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ftunivbergen:oai:bora.uib.no:1956/855 2023-05-15T14:51:06+02:00 Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard Cottier, Finlo Tverberg, Vigdis Inall, Mark Svendsen, Harald Nilsen, Frank Griffiths, Colin 2005-12-08 967424 bytes application/pdf https://hdl.handle.net/1956/855 https://doi.org/10.1029/2004jc002757 eng eng American Geophysical Union https://hdl.handle.net/1956/855 https://doi.org/10.1029/2004jc002757 Journal article 2005 ftunivbergen https://doi.org/10.1029/2004jc002757 2023-03-14T17:41:51Z Kongsfjorden and the West Spitsbergen Shelf is a region whose seasonal hydrography is dominated by the balance of Atlantic Water, Arctic waters, and glacial melt. Regional seasonality and the cross-shelf exchange processes have been investigated using conductivity-temperature-depth (CTD) observations from 2000–2003 and a 5-month mooring deployment through the spring and summer of 2002. Modeling of shelf-fjord dynamics was performed with the Bergen Ocean Model. Observations show a rapid and overwhelming intrusion of Atlantic Water across the shelf and into the fjord during midsummer giving rise to intense seasonality. Pockets of Atlantic Water, from the West Spitsbergen Current, form through barotropic instabilities at the shelf front. These leak onto the shelf and propagate as topographically steered features toward the fjord. Model results indicate that such cross-front exchange is enhanced by north winds. Normally, Atlantic Water penetration into the fjord is inhibited by a density front at the fjord mouth. This geostrophic control mechanism is found to be more important than the hydraulic control common to many fjords. Slow modification of the fjord water during spring reduces the effectiveness of geostrophic control, and by midsummer, Atlantic Water intrudes into the fjord, switching from being Arctic dominant to Atlantic dominant. Atlantic Water continues to intrude throughout the summer and by September reaches some quasi steady state condition. The fjord adopts a ‘‘cold’’ or ‘‘warm’’ mode according to the degree of Atlantic Water occupation. Horizontal exchange across the shelf may be an important process causing seasonal variability in the northward heat transport to the Arctic. Article in Journal/Newspaper Arctic Kongsfjord* Kongsfjorden Svalbard Spitsbergen University of Bergen: Bergen Open Research Archive (BORA-UiB) Arctic Bergen Svalbard Journal of Geophysical Research 110 C12 |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
description |
Kongsfjorden and the West Spitsbergen Shelf is a region whose seasonal hydrography is dominated by the balance of Atlantic Water, Arctic waters, and glacial melt. Regional seasonality and the cross-shelf exchange processes have been investigated using conductivity-temperature-depth (CTD) observations from 2000–2003 and a 5-month mooring deployment through the spring and summer of 2002. Modeling of shelf-fjord dynamics was performed with the Bergen Ocean Model. Observations show a rapid and overwhelming intrusion of Atlantic Water across the shelf and into the fjord during midsummer giving rise to intense seasonality. Pockets of Atlantic Water, from the West Spitsbergen Current, form through barotropic instabilities at the shelf front. These leak onto the shelf and propagate as topographically steered features toward the fjord. Model results indicate that such cross-front exchange is enhanced by north winds. Normally, Atlantic Water penetration into the fjord is inhibited by a density front at the fjord mouth. This geostrophic control mechanism is found to be more important than the hydraulic control common to many fjords. Slow modification of the fjord water during spring reduces the effectiveness of geostrophic control, and by midsummer, Atlantic Water intrudes into the fjord, switching from being Arctic dominant to Atlantic dominant. Atlantic Water continues to intrude throughout the summer and by September reaches some quasi steady state condition. The fjord adopts a ‘‘cold’’ or ‘‘warm’’ mode according to the degree of Atlantic Water occupation. Horizontal exchange across the shelf may be an important process causing seasonal variability in the northward heat transport to the Arctic. |
format |
Article in Journal/Newspaper |
author |
Cottier, Finlo Tverberg, Vigdis Inall, Mark Svendsen, Harald Nilsen, Frank Griffiths, Colin |
spellingShingle |
Cottier, Finlo Tverberg, Vigdis Inall, Mark Svendsen, Harald Nilsen, Frank Griffiths, Colin Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard |
author_facet |
Cottier, Finlo Tverberg, Vigdis Inall, Mark Svendsen, Harald Nilsen, Frank Griffiths, Colin |
author_sort |
Cottier, Finlo |
title |
Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard |
title_short |
Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard |
title_full |
Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard |
title_fullStr |
Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard |
title_full_unstemmed |
Water mass modification in an Arctic fjord through cross-shelf exchange: The seasonal hydrography of Kongsfjorden, Svalbard |
title_sort |
water mass modification in an arctic fjord through cross-shelf exchange: the seasonal hydrography of kongsfjorden, svalbard |
publisher |
American Geophysical Union |
publishDate |
2005 |
url |
https://hdl.handle.net/1956/855 https://doi.org/10.1029/2004jc002757 |
geographic |
Arctic Bergen Svalbard |
geographic_facet |
Arctic Bergen Svalbard |
genre |
Arctic Kongsfjord* Kongsfjorden Svalbard Spitsbergen |
genre_facet |
Arctic Kongsfjord* Kongsfjorden Svalbard Spitsbergen |
op_relation |
https://hdl.handle.net/1956/855 https://doi.org/10.1029/2004jc002757 |
op_doi |
https://doi.org/10.1029/2004jc002757 |
container_title |
Journal of Geophysical Research |
container_volume |
110 |
container_issue |
C12 |
_version_ |
1766322171350614016 |