The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model
The melt rate of Antarctic ice shelves is of key importance for rising sea levels and future climate scenarios. Recent observations beneath Larsen C Ice Shelf revealed an ocean boundary layer that was highly turbulent and raised questions on the effect of these rich flow dynamics on the ocean heat t...
Published in: | Journal of Physical Oceanography |
---|---|
Main Authors: | , , , , , |
Format: | Article in Journal/Newspaper |
Language: | unknown |
Published: |
American Meteorological Society
2022
|
Subjects: | |
Online Access: | http://nora.nerc.ac.uk/id/eprint/533219/ https://journals.ametsoc.org/view/journals/phoc/52/8/JPO-D-21-0166.1.xml |
id |
ftnerc:oai:nora.nerc.ac.uk:533219 |
---|---|
record_format |
openpolar |
spelling |
ftnerc:oai:nora.nerc.ac.uk:533219 2023-05-15T13:41:46+02:00 The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model Vreugdenhil, Catherine A. Taylor, John R. Davis, Peter E.D. Nicholls, Keith W. Holland, Paul R. Jenkins, Adrian 2022-08 http://nora.nerc.ac.uk/id/eprint/533219/ https://journals.ametsoc.org/view/journals/phoc/52/8/JPO-D-21-0166.1.xml unknown American Meteorological Society Vreugdenhil, Catherine A.; Taylor, John R.; Davis, Peter E.D. orcid:0000-0002-6471-6310 Nicholls, Keith W. orcid:0000-0002-2188-4509 Holland, Paul R. orcid:0000-0001-8370-289X Jenkins, Adrian. 2022 The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model. Journal of Physical Oceanography, 52 (8). 1903-1926. https://doi.org/10.1175/JPO-D-21-0166.1 <https://doi.org/10.1175/JPO-D-21-0166.1> Publication - Article PeerReviewed 2022 ftnerc https://doi.org/10.1175/JPO-D-21-0166.1 2023-02-04T19:53:36Z The melt rate of Antarctic ice shelves is of key importance for rising sea levels and future climate scenarios. Recent observations beneath Larsen C Ice Shelf revealed an ocean boundary layer that was highly turbulent and raised questions on the effect of these rich flow dynamics on the ocean heat transfer and the ice shelf melt rate. Directly motivated by the field observations, we have conducted large-eddy simulations (LES) to further examine the ocean boundary layer beneath Larsen C Ice Shelf. The LES was initialized with uniform temperature and salinity (T–S) and included a realistic tidal cycle and a small basal slope. A new parameterization based on previous work was applied at the top boundary to model near-wall turbulence and basal melting. The resulting vertical T–S profiles, melt rate, and friction velocity matched well with the Larsen C Ice Shelf observations. The instantaneous melt rate varied strongly with the tidal cycle, with faster flow increasing the turbulence and mixing of heat toward the ice base. An Ekman layer formed beneath the ice base and, due to the strong vertical shear of the current, Ekman rolls appeared in the mixed layer and stratified region (depth ≈ 20–60 m). In an additional high-resolution simulation (conducted with a smaller domain) the Ekman rolls were associated with increased turbulent kinetic energy, but a relatively small vertical heat flux. Our results will help with interpreting field observations and parameterizing the ocean-driven basal melting of ice shelves. Article in Journal/Newspaper Antarc* Antarctic Ice Shelf Ice Shelves Natural Environment Research Council: NERC Open Research Archive Antarctic Journal of Physical Oceanography 52 8 1903 1926 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
description |
The melt rate of Antarctic ice shelves is of key importance for rising sea levels and future climate scenarios. Recent observations beneath Larsen C Ice Shelf revealed an ocean boundary layer that was highly turbulent and raised questions on the effect of these rich flow dynamics on the ocean heat transfer and the ice shelf melt rate. Directly motivated by the field observations, we have conducted large-eddy simulations (LES) to further examine the ocean boundary layer beneath Larsen C Ice Shelf. The LES was initialized with uniform temperature and salinity (T–S) and included a realistic tidal cycle and a small basal slope. A new parameterization based on previous work was applied at the top boundary to model near-wall turbulence and basal melting. The resulting vertical T–S profiles, melt rate, and friction velocity matched well with the Larsen C Ice Shelf observations. The instantaneous melt rate varied strongly with the tidal cycle, with faster flow increasing the turbulence and mixing of heat toward the ice base. An Ekman layer formed beneath the ice base and, due to the strong vertical shear of the current, Ekman rolls appeared in the mixed layer and stratified region (depth ≈ 20–60 m). In an additional high-resolution simulation (conducted with a smaller domain) the Ekman rolls were associated with increased turbulent kinetic energy, but a relatively small vertical heat flux. Our results will help with interpreting field observations and parameterizing the ocean-driven basal melting of ice shelves. |
format |
Article in Journal/Newspaper |
author |
Vreugdenhil, Catherine A. Taylor, John R. Davis, Peter E.D. Nicholls, Keith W. Holland, Paul R. Jenkins, Adrian |
spellingShingle |
Vreugdenhil, Catherine A. Taylor, John R. Davis, Peter E.D. Nicholls, Keith W. Holland, Paul R. Jenkins, Adrian The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model |
author_facet |
Vreugdenhil, Catherine A. Taylor, John R. Davis, Peter E.D. Nicholls, Keith W. Holland, Paul R. Jenkins, Adrian |
author_sort |
Vreugdenhil, Catherine A. |
title |
The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model |
title_short |
The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model |
title_full |
The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model |
title_fullStr |
The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model |
title_full_unstemmed |
The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model |
title_sort |
ocean boundary layer beneath larsen c ice shelf: insights from large-eddy simulations with a near-wall model |
publisher |
American Meteorological Society |
publishDate |
2022 |
url |
http://nora.nerc.ac.uk/id/eprint/533219/ https://journals.ametsoc.org/view/journals/phoc/52/8/JPO-D-21-0166.1.xml |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic Ice Shelf Ice Shelves |
genre_facet |
Antarc* Antarctic Ice Shelf Ice Shelves |
op_relation |
Vreugdenhil, Catherine A.; Taylor, John R.; Davis, Peter E.D. orcid:0000-0002-6471-6310 Nicholls, Keith W. orcid:0000-0002-2188-4509 Holland, Paul R. orcid:0000-0001-8370-289X Jenkins, Adrian. 2022 The Ocean Boundary Layer beneath Larsen C Ice Shelf: Insights from Large-Eddy Simulations with a Near-Wall Model. Journal of Physical Oceanography, 52 (8). 1903-1926. https://doi.org/10.1175/JPO-D-21-0166.1 <https://doi.org/10.1175/JPO-D-21-0166.1> |
op_doi |
https://doi.org/10.1175/JPO-D-21-0166.1 |
container_title |
Journal of Physical Oceanography |
container_volume |
52 |
container_issue |
8 |
container_start_page |
1903 |
op_container_end_page |
1926 |
_version_ |
1766157969218600960 |