On the conditional frazil ice instability in seawater
It has been suggested that the presence of frazil ice can lead to a conditional instability in seawater. Any frazil forming in the water column reduces the bulk density of a parcel of frazil-seawater mixture, causing it to rise. Due to the pressure-decrease in the freezing point, this causes more fr...
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American Meteorological Society
2015
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Online Access: | http://nora.nerc.ac.uk/id/eprint/509870/ https://nora.nerc.ac.uk/id/eprint/509870/1/Jordan%20et%20al%202015%20-%20On%20the%20conditional%20frazil%20ice%20instability%20in%20seawater.pdf https://doi.org/10.1175/JPO-D-14-0159.1 |
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ftnerc:oai:nora.nerc.ac.uk:509870 2023-05-15T13:49:32+02:00 On the conditional frazil ice instability in seawater Jordan, James R. Kimura, Satoshi Holland, Paul R. Jenkins, Adrian Piggott, Matthew D. 2015-04 text http://nora.nerc.ac.uk/id/eprint/509870/ https://nora.nerc.ac.uk/id/eprint/509870/1/Jordan%20et%20al%202015%20-%20On%20the%20conditional%20frazil%20ice%20instability%20in%20seawater.pdf https://doi.org/10.1175/JPO-D-14-0159.1 en eng American Meteorological Society https://nora.nerc.ac.uk/id/eprint/509870/1/Jordan%20et%20al%202015%20-%20On%20the%20conditional%20frazil%20ice%20instability%20in%20seawater.pdf Jordan, James R.; Kimura, Satoshi orcid:0000-0003-1689-1605 Holland, Paul R. orcid:0000-0001-8370-289X Jenkins, Adrian orcid:0000-0002-9117-0616 Piggott, Matthew D. 2015 On the conditional frazil ice instability in seawater. Journal of Physical Oceanography, 45 (4). 1121-1138. https://doi.org/10.1175/JPO-D-14-0159.1 <https://doi.org/10.1175/JPO-D-14-0159.1> Marine Sciences Publication - Article PeerReviewed 2015 ftnerc https://doi.org/10.1175/JPO-D-14-0159.1 2023-02-04T19:41:04Z It has been suggested that the presence of frazil ice can lead to a conditional instability in seawater. Any frazil forming in the water column reduces the bulk density of a parcel of frazil-seawater mixture, causing it to rise. Due to the pressure-decrease in the freezing point, this causes more frazil to form, causing the parcel to accelerate, and so on. We use linear stability analysis and a non-hydrostatic ocean model to study this instability. We find that frazil ice growth caused by the rising of supercooled water is indeed able to generate a buoyancy-driven instability. Even in a gravitationally stable water column, the frazil ice mechanism can still generate convection. The instability does not operate in the presence of strong density stratification, high thermal driving (warm water), a small initial perturbation, high background mixing or the prevalence of large frazil ice crystals. In an unstable water column the instability is not necessarily expressed in frazil ice at all times; an initial frazil perturbation may melt and refreeze. Given a large enough initial perturbation this instability can allow significant ice growth. A model shows frazil ice growth in an Ice Shelf Water plume several kilometres from an ice shelf, under similar conditions to observations of frazil ice growth under sea ice. The presence of this instability could be a factor affecting the growth of sea ice near ice shelves, with implications for Antarctic bottom water formation. Article in Journal/Newspaper Antarc* Antarctic Ice Shelf Ice Shelves Sea ice Natural Environment Research Council: NERC Open Research Archive Antarctic Journal of Physical Oceanography 45 4 1121 1138 |
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Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
topic |
Marine Sciences |
spellingShingle |
Marine Sciences Jordan, James R. Kimura, Satoshi Holland, Paul R. Jenkins, Adrian Piggott, Matthew D. On the conditional frazil ice instability in seawater |
topic_facet |
Marine Sciences |
description |
It has been suggested that the presence of frazil ice can lead to a conditional instability in seawater. Any frazil forming in the water column reduces the bulk density of a parcel of frazil-seawater mixture, causing it to rise. Due to the pressure-decrease in the freezing point, this causes more frazil to form, causing the parcel to accelerate, and so on. We use linear stability analysis and a non-hydrostatic ocean model to study this instability. We find that frazil ice growth caused by the rising of supercooled water is indeed able to generate a buoyancy-driven instability. Even in a gravitationally stable water column, the frazil ice mechanism can still generate convection. The instability does not operate in the presence of strong density stratification, high thermal driving (warm water), a small initial perturbation, high background mixing or the prevalence of large frazil ice crystals. In an unstable water column the instability is not necessarily expressed in frazil ice at all times; an initial frazil perturbation may melt and refreeze. Given a large enough initial perturbation this instability can allow significant ice growth. A model shows frazil ice growth in an Ice Shelf Water plume several kilometres from an ice shelf, under similar conditions to observations of frazil ice growth under sea ice. The presence of this instability could be a factor affecting the growth of sea ice near ice shelves, with implications for Antarctic bottom water formation. |
format |
Article in Journal/Newspaper |
author |
Jordan, James R. Kimura, Satoshi Holland, Paul R. Jenkins, Adrian Piggott, Matthew D. |
author_facet |
Jordan, James R. Kimura, Satoshi Holland, Paul R. Jenkins, Adrian Piggott, Matthew D. |
author_sort |
Jordan, James R. |
title |
On the conditional frazil ice instability in seawater |
title_short |
On the conditional frazil ice instability in seawater |
title_full |
On the conditional frazil ice instability in seawater |
title_fullStr |
On the conditional frazil ice instability in seawater |
title_full_unstemmed |
On the conditional frazil ice instability in seawater |
title_sort |
on the conditional frazil ice instability in seawater |
publisher |
American Meteorological Society |
publishDate |
2015 |
url |
http://nora.nerc.ac.uk/id/eprint/509870/ https://nora.nerc.ac.uk/id/eprint/509870/1/Jordan%20et%20al%202015%20-%20On%20the%20conditional%20frazil%20ice%20instability%20in%20seawater.pdf https://doi.org/10.1175/JPO-D-14-0159.1 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Ice Shelf Ice Shelves Sea ice |
genre_facet |
Antarc* Antarctic Ice Shelf Ice Shelves Sea ice |
op_relation |
https://nora.nerc.ac.uk/id/eprint/509870/1/Jordan%20et%20al%202015%20-%20On%20the%20conditional%20frazil%20ice%20instability%20in%20seawater.pdf Jordan, James R.; Kimura, Satoshi orcid:0000-0003-1689-1605 Holland, Paul R. orcid:0000-0001-8370-289X Jenkins, Adrian orcid:0000-0002-9117-0616 Piggott, Matthew D. 2015 On the conditional frazil ice instability in seawater. Journal of Physical Oceanography, 45 (4). 1121-1138. https://doi.org/10.1175/JPO-D-14-0159.1 <https://doi.org/10.1175/JPO-D-14-0159.1> |
op_doi |
https://doi.org/10.1175/JPO-D-14-0159.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
45 |
container_issue |
4 |
container_start_page |
1121 |
op_container_end_page |
1138 |
_version_ |
1766251480199725056 |