Estimation of ice shelf melt rate in the presence of a thermohaline staircase
Diffusive convection–favorable thermohaline staircases are observed directly beneath George VI Ice Shelf, Antarctica. A thermohaline staircase is one of the most pronounced manifestations of double-diffusive convection. Cooling and freshening of the ocean by melting ice produces cool, freshwater abo...
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American Meteorological Society
2015
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ftnerc:oai:nora.nerc.ac.uk:508647 2023-05-15T13:48:08+02:00 Estimation of ice shelf melt rate in the presence of a thermohaline staircase Kimura, Satoshi Nicholls, Keith W. Venables, Emily 2015-01 text http://nora.nerc.ac.uk/id/eprint/508647/ https://nora.nerc.ac.uk/id/eprint/508647/1/JPO-D-14-0106.pdf https://doi.org/10.1175/JPO-D-14-0106.1 en eng American Meteorological Society https://nora.nerc.ac.uk/id/eprint/508647/1/JPO-D-14-0106.pdf Kimura, Satoshi orcid:0000-0003-1689-1605 Nicholls, Keith W. orcid:0000-0002-2188-4509 Venables, Emily. 2015 Estimation of ice shelf melt rate in the presence of a thermohaline staircase. Journal of Physical Oceanography, 45 (1). 133-148. https://doi.org/10.1175/JPO-D-14-0106.1 <https://doi.org/10.1175/JPO-D-14-0106.1> Publication - Article PeerReviewed 2015 ftnerc https://doi.org/10.1175/JPO-D-14-0106.1 2023-02-04T19:40:27Z Diffusive convection–favorable thermohaline staircases are observed directly beneath George VI Ice Shelf, Antarctica. A thermohaline staircase is one of the most pronounced manifestations of double-diffusive convection. Cooling and freshening of the ocean by melting ice produces cool, freshwater above the warmer, saltier water, the water mass distribution favorable to a type of double-diffusive convection known as diffusive convection. While the vertical distribution of water masses can be susceptible to diffusive convection, none of the observations beneath ice shelves so far have shown signals of this process and its effect on melting ice shelves is uncertain. The melt rate of ice shelves is commonly estimated using a parameterization based on a three-equation model, which assumes a fully developed, unstratified turbulent flow over hydraulically smooth surfaces. These prerequisites are clearly not met in the presence of a thermohaline staircase. The basal melt rate is estimated by applying an existing heat flux parameterization for diffusive convection in conjunction with the measurements of oceanic conditions at one site beneath George VI Ice Shelf. These estimates yield a possible range of melt rates between 0.1 and 1.3 m yr−1, where the observed melt rate of this site is ~1.4 m yr−1. Limitations of the formulation and implications of diffusive convection beneath ice shelves are discussed. Article in Journal/Newspaper Antarc* Antarctica George VI Ice Shelf Ice Shelf Ice Shelves Natural Environment Research Council: NERC Open Research Archive George VI Ice Shelf ENVELOPE(-67.840,-67.840,-71.692,-71.692) Journal of Physical Oceanography 45 1 133 148 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
Diffusive convection–favorable thermohaline staircases are observed directly beneath George VI Ice Shelf, Antarctica. A thermohaline staircase is one of the most pronounced manifestations of double-diffusive convection. Cooling and freshening of the ocean by melting ice produces cool, freshwater above the warmer, saltier water, the water mass distribution favorable to a type of double-diffusive convection known as diffusive convection. While the vertical distribution of water masses can be susceptible to diffusive convection, none of the observations beneath ice shelves so far have shown signals of this process and its effect on melting ice shelves is uncertain. The melt rate of ice shelves is commonly estimated using a parameterization based on a three-equation model, which assumes a fully developed, unstratified turbulent flow over hydraulically smooth surfaces. These prerequisites are clearly not met in the presence of a thermohaline staircase. The basal melt rate is estimated by applying an existing heat flux parameterization for diffusive convection in conjunction with the measurements of oceanic conditions at one site beneath George VI Ice Shelf. These estimates yield a possible range of melt rates between 0.1 and 1.3 m yr−1, where the observed melt rate of this site is ~1.4 m yr−1. Limitations of the formulation and implications of diffusive convection beneath ice shelves are discussed. |
format |
Article in Journal/Newspaper |
author |
Kimura, Satoshi Nicholls, Keith W. Venables, Emily |
spellingShingle |
Kimura, Satoshi Nicholls, Keith W. Venables, Emily Estimation of ice shelf melt rate in the presence of a thermohaline staircase |
author_facet |
Kimura, Satoshi Nicholls, Keith W. Venables, Emily |
author_sort |
Kimura, Satoshi |
title |
Estimation of ice shelf melt rate in the presence of a thermohaline staircase |
title_short |
Estimation of ice shelf melt rate in the presence of a thermohaline staircase |
title_full |
Estimation of ice shelf melt rate in the presence of a thermohaline staircase |
title_fullStr |
Estimation of ice shelf melt rate in the presence of a thermohaline staircase |
title_full_unstemmed |
Estimation of ice shelf melt rate in the presence of a thermohaline staircase |
title_sort |
estimation of ice shelf melt rate in the presence of a thermohaline staircase |
publisher |
American Meteorological Society |
publishDate |
2015 |
url |
http://nora.nerc.ac.uk/id/eprint/508647/ https://nora.nerc.ac.uk/id/eprint/508647/1/JPO-D-14-0106.pdf https://doi.org/10.1175/JPO-D-14-0106.1 |
long_lat |
ENVELOPE(-67.840,-67.840,-71.692,-71.692) |
geographic |
George VI Ice Shelf |
geographic_facet |
George VI Ice Shelf |
genre |
Antarc* Antarctica George VI Ice Shelf Ice Shelf Ice Shelves |
genre_facet |
Antarc* Antarctica George VI Ice Shelf Ice Shelf Ice Shelves |
op_relation |
https://nora.nerc.ac.uk/id/eprint/508647/1/JPO-D-14-0106.pdf Kimura, Satoshi orcid:0000-0003-1689-1605 Nicholls, Keith W. orcid:0000-0002-2188-4509 Venables, Emily. 2015 Estimation of ice shelf melt rate in the presence of a thermohaline staircase. Journal of Physical Oceanography, 45 (1). 133-148. https://doi.org/10.1175/JPO-D-14-0106.1 <https://doi.org/10.1175/JPO-D-14-0106.1> |
op_doi |
https://doi.org/10.1175/JPO-D-14-0106.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
45 |
container_issue |
1 |
container_start_page |
133 |
op_container_end_page |
148 |
_version_ |
1766248780559024128 |