Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea
A large fraction of Antarctic Bottom Water is produced in the Weddell Sea, through mixing between the cold and dense shelf water masses and the warm and saline off-shelf water. We present observations of the dense Filchner overflow plume from one mooring at the Filchner sill and two moorings located...
Published in: | Journal of Physical Oceanography |
---|---|
Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
American Meteorological Society
2019
|
Subjects: | |
Online Access: | https://hdl.handle.net/1956/19821 https://doi.org/10.1175/jpo-d-18-0093.1 |
id |
ftunivbergen:oai:bora.uib.no:1956/19821 |
---|---|
record_format |
openpolar |
spelling |
ftunivbergen:oai:bora.uib.no:1956/19821 2023-05-15T13:35:04+02:00 Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea Daae, Kjersti Fer, Ilker Darelius, Elin Maria K. 2019-01-24T09:06:53Z application/pdf https://hdl.handle.net/1956/19821 https://doi.org/10.1175/jpo-d-18-0093.1 eng eng American Meteorological Society https://journals.ametsoc.org/doi/abs/10.1175/JPO-D-18-0093.1 Norges forskningsråd: 231549 Norges forskningsråd: 211415 urn:issn:0022-3670 urn:issn:1520-0485 https://hdl.handle.net/1956/19821 https://doi.org/10.1175/jpo-d-18-0093.1 cristin:1627357 Attribution CC BY http://creativecommons.org/licenses/by/4.0 Copyright 2018 American Meteorological Society Journal of Physical Oceanography Potential vorticity Transport Bottom currents/bottom water Density currents Fronts Mixing Peer reviewed Journal article 2019 ftunivbergen https://doi.org/10.1175/jpo-d-18-0093.1 2023-03-14T17:39:29Z A large fraction of Antarctic Bottom Water is produced in the Weddell Sea, through mixing between the cold and dense shelf water masses and the warm and saline off-shelf water. We present observations of the dense Filchner overflow plume from one mooring at the Filchner sill and two moorings located downstream, on the continental slope. The plume variability over the continental slope at a monthly time scale is related to upstream conditions at the Filchner sill, with a high correlation in density. Revised column-integrated volume transport calculations across the Filchner sill indicate 50% higher values in 2010 compared with the earlier estimates available from 1985. Over the continental slope, the plume thickness fluctuates strongly between less than 25 m and more than 250 m. Observations of elevated temperature variance and high Froude numbers at the plume interface imply high mixing rates and entrainment of ambient water masses. The mixing events typically coincide with shear spikes across the plume. The shear spikes appear quasi-periodically, when counterrotating oscillations with periods of 24 and 72 h align. The clockwise 24-h oscillation is related to diurnal, barotropic tidal currents and topographic vorticity waves, whereas the counterclockwise 72-h oscillation is related to vortex stretching or topographic vorticity waves. publishedVersion Article in Journal/Newspaper Antarc* Antarctic Weddell Sea University of Bergen: Bergen Open Research Archive (BORA-UiB) Antarctic Weddell Weddell Sea Journal of Physical Oceanography 49 1 3 20 |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
topic |
Potential vorticity Transport Bottom currents/bottom water Density currents Fronts Mixing |
spellingShingle |
Potential vorticity Transport Bottom currents/bottom water Density currents Fronts Mixing Daae, Kjersti Fer, Ilker Darelius, Elin Maria K. Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea |
topic_facet |
Potential vorticity Transport Bottom currents/bottom water Density currents Fronts Mixing |
description |
A large fraction of Antarctic Bottom Water is produced in the Weddell Sea, through mixing between the cold and dense shelf water masses and the warm and saline off-shelf water. We present observations of the dense Filchner overflow plume from one mooring at the Filchner sill and two moorings located downstream, on the continental slope. The plume variability over the continental slope at a monthly time scale is related to upstream conditions at the Filchner sill, with a high correlation in density. Revised column-integrated volume transport calculations across the Filchner sill indicate 50% higher values in 2010 compared with the earlier estimates available from 1985. Over the continental slope, the plume thickness fluctuates strongly between less than 25 m and more than 250 m. Observations of elevated temperature variance and high Froude numbers at the plume interface imply high mixing rates and entrainment of ambient water masses. The mixing events typically coincide with shear spikes across the plume. The shear spikes appear quasi-periodically, when counterrotating oscillations with periods of 24 and 72 h align. The clockwise 24-h oscillation is related to diurnal, barotropic tidal currents and topographic vorticity waves, whereas the counterclockwise 72-h oscillation is related to vortex stretching or topographic vorticity waves. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Daae, Kjersti Fer, Ilker Darelius, Elin Maria K. |
author_facet |
Daae, Kjersti Fer, Ilker Darelius, Elin Maria K. |
author_sort |
Daae, Kjersti |
title |
Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea |
title_short |
Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea |
title_full |
Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea |
title_fullStr |
Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea |
title_full_unstemmed |
Variability and mixing of the Filchner overflow plume on the continental slope,Weddell Sea |
title_sort |
variability and mixing of the filchner overflow plume on the continental slope,weddell sea |
publisher |
American Meteorological Society |
publishDate |
2019 |
url |
https://hdl.handle.net/1956/19821 https://doi.org/10.1175/jpo-d-18-0093.1 |
geographic |
Antarctic Weddell Weddell Sea |
geographic_facet |
Antarctic Weddell Weddell Sea |
genre |
Antarc* Antarctic Weddell Sea |
genre_facet |
Antarc* Antarctic Weddell Sea |
op_source |
Journal of Physical Oceanography |
op_relation |
https://journals.ametsoc.org/doi/abs/10.1175/JPO-D-18-0093.1 Norges forskningsråd: 231549 Norges forskningsråd: 211415 urn:issn:0022-3670 urn:issn:1520-0485 https://hdl.handle.net/1956/19821 https://doi.org/10.1175/jpo-d-18-0093.1 cristin:1627357 |
op_rights |
Attribution CC BY http://creativecommons.org/licenses/by/4.0 Copyright 2018 American Meteorological Society |
op_doi |
https://doi.org/10.1175/jpo-d-18-0093.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
49 |
container_issue |
1 |
container_start_page |
3 |
op_container_end_page |
20 |
_version_ |
1766060581309120512 |