Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica
The surface of windy Antarctic snowfields is subject to drifting snow, which leads to the formation of sastrugi. In turn, sastrugi contribute to the drag exerted by the snowsurface on the atmosphere and hence influence drifting snow. Although the surface drag over rough sastrugi fields has been esti...
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Language: | English |
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ftcemoa:oai:irsteadoc.irstea.fr:PUB00057155 2023-05-15T13:04:22+02:00 Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica Amory, C. Gallee, H. Naaim-Bouvet, F. Favier, V. Vignon, E. Picard, G. Trouvilliez, A. Piard, L. Genthon, C. Bellot, H. IRD UMR 5001 IGE GRENOBLE FRA IRSTEA GRENOBLE UR ETGR FRA ANTARCTIQUE 2017 application/pdf https://irsteadoc.irstea.fr/cemoa/PUB00057155 Anglais eng http://dx.doi.org/10.1007/s10546-017-0242-5 https://irsteadoc.irstea.fr/cemoa/PUB00057155 Date de dépôt: 2018-03-01 - Tous les documents et informations contenus dans la base CemOA Publications sont protégés en vertu du droit de propriété intellectuelle, en particulier par le droit d'auteur. La personne consultant la base CemOA Publications peut visualiser, reproduire, ou stocker des copies des publications, à condition que l'information soit seulement pour son usage personnel et non commercial. L'utilisation des travaux universitaires est soumise à autorisation préalable de leurs auteurs. Toute information relative au signalement d'une publication contenue dans CemOA Publications doit inclure la citation bibliographique usuelle : Nom du ou des auteurs, titre et source du document, date et URL de la notice (dc_identifier). 50493 COEFFICIENT DE FROTTEMENT TRANSPORT DE NEIGE PAR LE VENT RUGOSITE drifting snow roughness Article de revue scientifique à comité de lecture 2017 ftcemoa https://doi.org/10.1007/s10546-017-0242-5 2021-06-29T12:07:54Z The surface of windy Antarctic snowfields is subject to drifting snow, which leads to the formation of sastrugi. In turn, sastrugi contribute to the drag exerted by the snowsurface on the atmosphere and hence influence drifting snow. Although the surface drag over rough sastrugi fields has been estimated for individual locations in Antarctica, its variation over time and with respect to drifting snow has received little attention. Using year-round data from a meteorological mast, seasonal variations in the neutral drag coefficient at a height of 10m (C-DN10) in coastal Adelie Land are presented and discussed in light of the formation and behaviour of sastrugi based on observed aeolian erosion patterns. The measurements revealed high C-DN10 values (>= 2 x 10(-3)) and limited drifting snow (35% of the time) in summer (December-February) versus lower C-DN10 values (approximate to 1.5 x 10(-3)) associated with more frequent drifting snow (70% of the time) in winter (March-November). Without the seasonal distinction, there was no clear dependence of C-DN10 on friction velocity or wind direction, but observations revealed a general increase in C-DN10 with rising air temperature. Themain hypothesis defended here is that higher temperatures increase snowcohesion and the development of sastrugi just after snow deposition while inhibiting the sastrugi streamlining process by raising the erosion threshold. This increases the contribution of the sastrugi form drag to the total surface drag in summer when winds are lighter and more variable. The analysis also showed that, in the absence of erosion, single snowfall events can reduce C-DN10 to 1 x 10(-3) due to the burying of pre-existing microrelief under newly deposited snow. The results suggest that polar atmospheric models should account for spatial and temporal variations in snow surface roughness through a dynamic representation of the sastrugi form drag. Article in Journal/Newspaper Adelie Land Antarc* Antarctic Antarctica Antarctique* East Antarctica Irstea Publications et Bases documentaires (Irstea@doc/CemOA) Antarctic East Antarctica Sastrugi ENVELOPE(163.683,163.683,-74.617,-74.617) Boundary-Layer Meteorology 164 1 107 133 |
institution |
Open Polar |
collection |
Irstea Publications et Bases documentaires (Irstea@doc/CemOA) |
op_collection_id |
ftcemoa |
language |
English |
topic |
COEFFICIENT DE FROTTEMENT TRANSPORT DE NEIGE PAR LE VENT RUGOSITE drifting snow roughness |
spellingShingle |
COEFFICIENT DE FROTTEMENT TRANSPORT DE NEIGE PAR LE VENT RUGOSITE drifting snow roughness Amory, C. Gallee, H. Naaim-Bouvet, F. Favier, V. Vignon, E. Picard, G. Trouvilliez, A. Piard, L. Genthon, C. Bellot, H. Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica |
topic_facet |
COEFFICIENT DE FROTTEMENT TRANSPORT DE NEIGE PAR LE VENT RUGOSITE drifting snow roughness |
description |
The surface of windy Antarctic snowfields is subject to drifting snow, which leads to the formation of sastrugi. In turn, sastrugi contribute to the drag exerted by the snowsurface on the atmosphere and hence influence drifting snow. Although the surface drag over rough sastrugi fields has been estimated for individual locations in Antarctica, its variation over time and with respect to drifting snow has received little attention. Using year-round data from a meteorological mast, seasonal variations in the neutral drag coefficient at a height of 10m (C-DN10) in coastal Adelie Land are presented and discussed in light of the formation and behaviour of sastrugi based on observed aeolian erosion patterns. The measurements revealed high C-DN10 values (>= 2 x 10(-3)) and limited drifting snow (35% of the time) in summer (December-February) versus lower C-DN10 values (approximate to 1.5 x 10(-3)) associated with more frequent drifting snow (70% of the time) in winter (March-November). Without the seasonal distinction, there was no clear dependence of C-DN10 on friction velocity or wind direction, but observations revealed a general increase in C-DN10 with rising air temperature. Themain hypothesis defended here is that higher temperatures increase snowcohesion and the development of sastrugi just after snow deposition while inhibiting the sastrugi streamlining process by raising the erosion threshold. This increases the contribution of the sastrugi form drag to the total surface drag in summer when winds are lighter and more variable. The analysis also showed that, in the absence of erosion, single snowfall events can reduce C-DN10 to 1 x 10(-3) due to the burying of pre-existing microrelief under newly deposited snow. The results suggest that polar atmospheric models should account for spatial and temporal variations in snow surface roughness through a dynamic representation of the sastrugi form drag. |
author2 |
IRD UMR 5001 IGE GRENOBLE FRA IRSTEA GRENOBLE UR ETGR FRA |
format |
Article in Journal/Newspaper |
author |
Amory, C. Gallee, H. Naaim-Bouvet, F. Favier, V. Vignon, E. Picard, G. Trouvilliez, A. Piard, L. Genthon, C. Bellot, H. |
author_facet |
Amory, C. Gallee, H. Naaim-Bouvet, F. Favier, V. Vignon, E. Picard, G. Trouvilliez, A. Piard, L. Genthon, C. Bellot, H. |
author_sort |
Amory, C. |
title |
Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica |
title_short |
Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica |
title_full |
Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica |
title_fullStr |
Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica |
title_full_unstemmed |
Seasonal variations in drag coefficient over a Sastrugi-covered snowfield in coastal East Antarctica |
title_sort |
seasonal variations in drag coefficient over a sastrugi-covered snowfield in coastal east antarctica |
publishDate |
2017 |
url |
https://irsteadoc.irstea.fr/cemoa/PUB00057155 |
op_coverage |
ANTARCTIQUE |
long_lat |
ENVELOPE(163.683,163.683,-74.617,-74.617) |
geographic |
Antarctic East Antarctica Sastrugi |
geographic_facet |
Antarctic East Antarctica Sastrugi |
genre |
Adelie Land Antarc* Antarctic Antarctica Antarctique* East Antarctica |
genre_facet |
Adelie Land Antarc* Antarctic Antarctica Antarctique* East Antarctica |
op_source |
50493 |
op_relation |
http://dx.doi.org/10.1007/s10546-017-0242-5 https://irsteadoc.irstea.fr/cemoa/PUB00057155 |
op_rights |
Date de dépôt: 2018-03-01 - Tous les documents et informations contenus dans la base CemOA Publications sont protégés en vertu du droit de propriété intellectuelle, en particulier par le droit d'auteur. La personne consultant la base CemOA Publications peut visualiser, reproduire, ou stocker des copies des publications, à condition que l'information soit seulement pour son usage personnel et non commercial. L'utilisation des travaux universitaires est soumise à autorisation préalable de leurs auteurs. Toute information relative au signalement d'une publication contenue dans CemOA Publications doit inclure la citation bibliographique usuelle : Nom du ou des auteurs, titre et source du document, date et URL de la notice (dc_identifier). |
op_doi |
https://doi.org/10.1007/s10546-017-0242-5 |
container_title |
Boundary-Layer Meteorology |
container_volume |
164 |
container_issue |
1 |
container_start_page |
107 |
op_container_end_page |
133 |
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1766357961695821824 |