The dynamics of idealized katabatic flow over a moderate slope and ice shelf
A non-hydrostatic numerical weather prediction model has been employed to Simulate idealized katabatic flows over a moderate slope and adjoining ice shelf. The topography of Coats Land and the adjoining Brunt Ice Shelf. Antarctica. has been used: this is typical of much of the Antarctic coastline. T...
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Online Access: | http://nora.nerc.ac.uk/id/eprint/12377/ http://onlinelibrary.wiley.com/doi/10.1256/qj.03.24/abstract |
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ftnerc:oai:nora.nerc.ac.uk:12377 2023-05-15T13:45:11+02:00 The dynamics of idealized katabatic flow over a moderate slope and ice shelf Renfrew, Ian A. 2004 http://nora.nerc.ac.uk/id/eprint/12377/ http://onlinelibrary.wiley.com/doi/10.1256/qj.03.24/abstract unknown Royal Meteorological Society Renfrew, Ian A. 2004 The dynamics of idealized katabatic flow over a moderate slope and ice shelf. Quarterly Journal of the Royal Meteorological Society, 130 (Pt. A, No. 598). 1023-1045. https://doi.org/10.1256/qj.03.24 <https://doi.org/10.1256/qj.03.24> Atmospheric Sciences Publication - Article PeerReviewed 2004 ftnerc https://doi.org/10.1256/qj.03.24 2023-02-04T19:27:55Z A non-hydrostatic numerical weather prediction model has been employed to Simulate idealized katabatic flows over a moderate slope and adjoining ice shelf. The topography of Coats Land and the adjoining Brunt Ice Shelf. Antarctica. has been used: this is typical of much of the Antarctic coastline. The Regional Atmospheric Modeling System Version 4.3 has been adapted for simulations over compacted snow, most notably through changes to the multi-layer soil model. The Simulations are initialized using clear-sky conditions and at rest. On the slope. a shallow katabatic flow develops, the winds becoming approximately steady on the slope by similar to12 h. The peak downslope winds are about 7 m s(-1) at 30 m above the snow surface. The katabatic flow depth ranges from 50 to 100 m down the slope. Over the ice shelf the katabatic flow peters out, while a pool of cold air develops, primarily through sensible-heat loss into the surface and partially balancing the net radiative-heat loss to space. Near-surface and Sounding data from the model simulations compare well with archetypal and typical katabatic flow observations. especially after some tuning of the model's turbulence parametrization. An analysis of the downslope flow dynamics shows the buoyancy force is generally balanced by the inertial force. except towards the foot of the slope where it is balanced by upslope forces related to gradients in the potential-temperature deficit and katabatic-layer height. caused by the pool of cold air over the ice shelf. Over time, the cooling of the ice shelf boundary layer leads to an apparent retreat of the katabatic flow from the ice shelf and some way up the slope. The dynamical analysis explains the surface climatology observed, such that the persistent katabatic winds of Coats Land rarely reach the Brunt Ice Shelf. The simulated katabatic flow moves from 'shooting' to 'tranquil' towards the foot of the slope. This transition acts to trigger a train of internal gravity waves which propagate energy upwards away from the ... Article in Journal/Newspaper Antarc* Antarctic Antarctica Brunt Ice Shelf Ice Shelf Natural Environment Research Council: NERC Open Research Archive Antarctic The Antarctic Coats Land ENVELOPE(-27.500,-27.500,-77.000,-77.000) Brunt Ice Shelf ENVELOPE(-22.500,-22.500,-74.750,-74.750) Quarterly Journal of the Royal Meteorological Society 130 598 1023 1045 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
unknown |
topic |
Atmospheric Sciences |
spellingShingle |
Atmospheric Sciences Renfrew, Ian A. The dynamics of idealized katabatic flow over a moderate slope and ice shelf |
topic_facet |
Atmospheric Sciences |
description |
A non-hydrostatic numerical weather prediction model has been employed to Simulate idealized katabatic flows over a moderate slope and adjoining ice shelf. The topography of Coats Land and the adjoining Brunt Ice Shelf. Antarctica. has been used: this is typical of much of the Antarctic coastline. The Regional Atmospheric Modeling System Version 4.3 has been adapted for simulations over compacted snow, most notably through changes to the multi-layer soil model. The Simulations are initialized using clear-sky conditions and at rest. On the slope. a shallow katabatic flow develops, the winds becoming approximately steady on the slope by similar to12 h. The peak downslope winds are about 7 m s(-1) at 30 m above the snow surface. The katabatic flow depth ranges from 50 to 100 m down the slope. Over the ice shelf the katabatic flow peters out, while a pool of cold air develops, primarily through sensible-heat loss into the surface and partially balancing the net radiative-heat loss to space. Near-surface and Sounding data from the model simulations compare well with archetypal and typical katabatic flow observations. especially after some tuning of the model's turbulence parametrization. An analysis of the downslope flow dynamics shows the buoyancy force is generally balanced by the inertial force. except towards the foot of the slope where it is balanced by upslope forces related to gradients in the potential-temperature deficit and katabatic-layer height. caused by the pool of cold air over the ice shelf. Over time, the cooling of the ice shelf boundary layer leads to an apparent retreat of the katabatic flow from the ice shelf and some way up the slope. The dynamical analysis explains the surface climatology observed, such that the persistent katabatic winds of Coats Land rarely reach the Brunt Ice Shelf. The simulated katabatic flow moves from 'shooting' to 'tranquil' towards the foot of the slope. This transition acts to trigger a train of internal gravity waves which propagate energy upwards away from the ... |
format |
Article in Journal/Newspaper |
author |
Renfrew, Ian A. |
author_facet |
Renfrew, Ian A. |
author_sort |
Renfrew, Ian A. |
title |
The dynamics of idealized katabatic flow over a moderate slope and ice shelf |
title_short |
The dynamics of idealized katabatic flow over a moderate slope and ice shelf |
title_full |
The dynamics of idealized katabatic flow over a moderate slope and ice shelf |
title_fullStr |
The dynamics of idealized katabatic flow over a moderate slope and ice shelf |
title_full_unstemmed |
The dynamics of idealized katabatic flow over a moderate slope and ice shelf |
title_sort |
dynamics of idealized katabatic flow over a moderate slope and ice shelf |
publisher |
Royal Meteorological Society |
publishDate |
2004 |
url |
http://nora.nerc.ac.uk/id/eprint/12377/ http://onlinelibrary.wiley.com/doi/10.1256/qj.03.24/abstract |
long_lat |
ENVELOPE(-27.500,-27.500,-77.000,-77.000) ENVELOPE(-22.500,-22.500,-74.750,-74.750) |
geographic |
Antarctic The Antarctic Coats Land Brunt Ice Shelf |
geographic_facet |
Antarctic The Antarctic Coats Land Brunt Ice Shelf |
genre |
Antarc* Antarctic Antarctica Brunt Ice Shelf Ice Shelf |
genre_facet |
Antarc* Antarctic Antarctica Brunt Ice Shelf Ice Shelf |
op_relation |
Renfrew, Ian A. 2004 The dynamics of idealized katabatic flow over a moderate slope and ice shelf. Quarterly Journal of the Royal Meteorological Society, 130 (Pt. A, No. 598). 1023-1045. https://doi.org/10.1256/qj.03.24 <https://doi.org/10.1256/qj.03.24> |
op_doi |
https://doi.org/10.1256/qj.03.24 |
container_title |
Quarterly Journal of the Royal Meteorological Society |
container_volume |
130 |
container_issue |
598 |
container_start_page |
1023 |
op_container_end_page |
1045 |
_version_ |
1766215066252738560 |