Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica
The katabatic wind events observed in the coastal zone of Adelie Land, Antarctica, on 27 November and 3 December 1985 are simulated with a hydrostatic mesoscale atmospheric model coupled to a snow moder. The diurnal cycle of insolation is strong. The main difference in the forcing between the two ev...
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ftunivlouvain:oai:dial.uclouvain.be:boreal:45316 2024-05-19T07:27:29+00:00 Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica Gallee, H. Pettre, P UCL 1998 http://hdl.handle.net/2078.1/45316 https://doi.org/10.1175/1520-0469(1998)055<1755:DCOKWC>2.0.CO;2 eng eng Amer Meteorological Soc boreal:45316 http://hdl.handle.net/2078.1/45316 doi:10.1175/1520-0469(1998)055<1755:DCOKWC>2.0.CO;2 urn:ISSN:0022-4928 urn:EISSN:1520-0469 Journal of the Atmospheric Sciences, Vol. 55, no. 10, p. 1755-1770 (1998) info:eu-repo/semantics/article 1998 ftunivlouvain https://doi.org/10.1175/1520-0469(1998)055<1755:DCOKWC>2.0.CO;2 2024-04-24T01:48:21Z The katabatic wind events observed in the coastal zone of Adelie Land, Antarctica, on 27 November and 3 December 1985 are simulated with a hydrostatic mesoscale atmospheric model coupled to a snow moder. The diurnal cycle of insolation is strong. The main difference in the forcing between the two events is the large-scale wind, which is weak on 27 November and moderate on 3 December. In both cases temperature and wind are characterized by well-marked diurnal cycles. In particular, katabatic winds blow during nighttime and upslope winds during daytime. In both cases the katabatic airstream slows down progressively over the ocean. Consequently, continental air piles up and this generates a pool of cold air responsible for a pressure gradient force opposing the katabatic wind. An amplification of the slowing down results. When, in the morning, insolation increases, the surface inversion weakens but the influence of the cold air pool increases. The katabatic how starts to decay over the coastal zone and then retreats progressively toward the ice sheet interior. When the large-scale wind is weak, the surface warming is sufficient for generating an additional upslope bouyancy force, and anabatic flow develops over the ice sheet in the afternoon. When the large-scare wind is moderate and downslope, the pilling up of cold air is important and this has a dramatic impact on the flow. A sharp spatial transition is generated between downslope and upslope winds over the ocean. This discontinuity moves toward the ice sheet interior in the morning and is responsible for the sudden cessation of the katabatic flow seen by static observers. The results of the simulations are used in order to refine a simple parameterization of Antarctic katabatic winds. Article in Journal/Newspaper Adelie Land Antarc* Antarctic Antarctica Ice Sheet DIAL@UCLouvain (Université catholique de Louvain) |
institution |
Open Polar |
collection |
DIAL@UCLouvain (Université catholique de Louvain) |
op_collection_id |
ftunivlouvain |
language |
English |
description |
The katabatic wind events observed in the coastal zone of Adelie Land, Antarctica, on 27 November and 3 December 1985 are simulated with a hydrostatic mesoscale atmospheric model coupled to a snow moder. The diurnal cycle of insolation is strong. The main difference in the forcing between the two events is the large-scale wind, which is weak on 27 November and moderate on 3 December. In both cases temperature and wind are characterized by well-marked diurnal cycles. In particular, katabatic winds blow during nighttime and upslope winds during daytime. In both cases the katabatic airstream slows down progressively over the ocean. Consequently, continental air piles up and this generates a pool of cold air responsible for a pressure gradient force opposing the katabatic wind. An amplification of the slowing down results. When, in the morning, insolation increases, the surface inversion weakens but the influence of the cold air pool increases. The katabatic how starts to decay over the coastal zone and then retreats progressively toward the ice sheet interior. When the large-scale wind is weak, the surface warming is sufficient for generating an additional upslope bouyancy force, and anabatic flow develops over the ice sheet in the afternoon. When the large-scare wind is moderate and downslope, the pilling up of cold air is important and this has a dramatic impact on the flow. A sharp spatial transition is generated between downslope and upslope winds over the ocean. This discontinuity moves toward the ice sheet interior in the morning and is responsible for the sudden cessation of the katabatic flow seen by static observers. The results of the simulations are used in order to refine a simple parameterization of Antarctic katabatic winds. |
author2 |
UCL |
format |
Article in Journal/Newspaper |
author |
Gallee, H. Pettre, P |
spellingShingle |
Gallee, H. Pettre, P Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica |
author_facet |
Gallee, H. Pettre, P |
author_sort |
Gallee, H. |
title |
Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica |
title_short |
Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica |
title_full |
Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica |
title_fullStr |
Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica |
title_full_unstemmed |
Dynamical constraints on Katabatic Wind Cessation in Adelie Land, Antarctica |
title_sort |
dynamical constraints on katabatic wind cessation in adelie land, antarctica |
publisher |
Amer Meteorological Soc |
publishDate |
1998 |
url |
http://hdl.handle.net/2078.1/45316 https://doi.org/10.1175/1520-0469(1998)055<1755:DCOKWC>2.0.CO;2 |
genre |
Adelie Land Antarc* Antarctic Antarctica Ice Sheet |
genre_facet |
Adelie Land Antarc* Antarctic Antarctica Ice Sheet |
op_source |
Journal of the Atmospheric Sciences, Vol. 55, no. 10, p. 1755-1770 (1998) |
op_relation |
boreal:45316 http://hdl.handle.net/2078.1/45316 doi:10.1175/1520-0469(1998)055<1755:DCOKWC>2.0.CO;2 urn:ISSN:0022-4928 urn:EISSN:1520-0469 |
op_doi |
https://doi.org/10.1175/1520-0469(1998)055<1755:DCOKWC>2.0.CO;2 |
_version_ |
1799477168214900736 |