Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi
[Departement_IRSTEA]Eaux [TR1_IRSTEA]RIVAGE International audience In polar regions, sastrugi are a direct manifestation of drifting snow and form the main surface roughness elements. In turn, sastrugi alter the generation of atmospheric turbulence and thus modify the wind field and the aeolian snow...
Published in: | The Cryosphere |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Online Access: | https://insu.hal.science/insu-01388863 https://insu.hal.science/insu-01388863/document https://insu.hal.science/insu-01388863/file/CRYOSPHERE%20-%20Brief%20communication%20Two%20well-marked%20cases%20of%20aerodynamic%20adjustment%20of%20sastrugi.pdf https://doi.org/10.5194/tc-10-743-2016 |
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ftunigrenoble:oai:HAL:insu-01388863v1 2024-04-14T08:03:55+00:00 Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi Amory, Charles Naaim-Bouvet, F. Gallée, H Vignon, E Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ) Erosion torrentielle neige et avalanches (UR ETGR (ETNA)) Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) 2016 https://insu.hal.science/insu-01388863 https://insu.hal.science/insu-01388863/document https://insu.hal.science/insu-01388863/file/CRYOSPHERE%20-%20Brief%20communication%20Two%20well-marked%20cases%20of%20aerodynamic%20adjustment%20of%20sastrugi.pdf https://doi.org/10.5194/tc-10-743-2016 en eng HAL CCSD Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-10-743-2016 insu-01388863 https://insu.hal.science/insu-01388863 https://insu.hal.science/insu-01388863/document https://insu.hal.science/insu-01388863/file/CRYOSPHERE%20-%20Brief%20communication%20Two%20well-marked%20cases%20of%20aerodynamic%20adjustment%20of%20sastrugi.pdf doi:10.5194/tc-10-743-2016 IRSTEA: PUB00054166 info:eu-repo/semantics/OpenAccess ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://insu.hal.science/insu-01388863 The Cryosphere, 2016, 10 (2), pp.743 - 750. ⟨10.5194/tc-10-743-2016⟩ ADELIE [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology info:eu-repo/semantics/article Journal articles 2016 ftunigrenoble https://doi.org/10.5194/tc-10-743-2016 2024-03-21T16:28:44Z [Departement_IRSTEA]Eaux [TR1_IRSTEA]RIVAGE International audience In polar regions, sastrugi are a direct manifestation of drifting snow and form the main surface roughness elements. In turn, sastrugi alter the generation of atmospheric turbulence and thus modify the wind field and the aeolian snow mass fluxes. Little attention has been paid to these feedback processes, mainly because of experimental difficulties. As a result, most polar atmospheric models currently ignore sastrugi over snow-covered regions. This paper aims at quantifying the potential influence of sastrugi on the local wind field and on snow erosion over a sastrugi-covered snowfield in coastal Adélie Land, East Antarctica. We focus on two erosion events during which sastrugi responses to shifts in wind direction have been interpreted from temporal variations in drag and aeolian snow mass flux measurements during austral winter 2013. Using this data set, it is shown that (i) neutral stability, 10 m drag coefficient (C DN10) values are in the range of 1.3–1.5 × 10 −3 when the wind is well aligned with the sastrugi, (ii) as the wind shifts by only 20– 30° away from the streamlined direction, C DN10 increases (by 30–120 %) and the aeolian snow mass flux decreases (by 30–80 %), thereby reflecting the growing contribution of the sastrugi form drag to the total surface drag and its inhibiting effect on snow erosion, (iii) the timescale of sastrugi aerodynamic adjustment can be as short as 3 h for friction velocities greater than 1 m s −1 and during strong drifting snow conditions and (iv) knowing C DN10 is not sufficient to estimate the snow erosion flux that results from drag partitioning at the surface because C DN10 includes the contribution of the sas-trugi form drag. Article in Journal/Newspaper Antarc* Antarctica East Antarctica The Cryosphere Université Grenoble Alpes: HAL Austral East Antarctica Sastrugi ENVELOPE(163.683,163.683,-74.617,-74.617) The Cryosphere 10 2 743 750 |
institution |
Open Polar |
collection |
Université Grenoble Alpes: HAL |
op_collection_id |
ftunigrenoble |
language |
English |
topic |
ADELIE [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
spellingShingle |
ADELIE [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology Amory, Charles Naaim-Bouvet, F. Gallée, H Vignon, E Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi |
topic_facet |
ADELIE [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology |
description |
[Departement_IRSTEA]Eaux [TR1_IRSTEA]RIVAGE International audience In polar regions, sastrugi are a direct manifestation of drifting snow and form the main surface roughness elements. In turn, sastrugi alter the generation of atmospheric turbulence and thus modify the wind field and the aeolian snow mass fluxes. Little attention has been paid to these feedback processes, mainly because of experimental difficulties. As a result, most polar atmospheric models currently ignore sastrugi over snow-covered regions. This paper aims at quantifying the potential influence of sastrugi on the local wind field and on snow erosion over a sastrugi-covered snowfield in coastal Adélie Land, East Antarctica. We focus on two erosion events during which sastrugi responses to shifts in wind direction have been interpreted from temporal variations in drag and aeolian snow mass flux measurements during austral winter 2013. Using this data set, it is shown that (i) neutral stability, 10 m drag coefficient (C DN10) values are in the range of 1.3–1.5 × 10 −3 when the wind is well aligned with the sastrugi, (ii) as the wind shifts by only 20– 30° away from the streamlined direction, C DN10 increases (by 30–120 %) and the aeolian snow mass flux decreases (by 30–80 %), thereby reflecting the growing contribution of the sastrugi form drag to the total surface drag and its inhibiting effect on snow erosion, (iii) the timescale of sastrugi aerodynamic adjustment can be as short as 3 h for friction velocities greater than 1 m s −1 and during strong drifting snow conditions and (iv) knowing C DN10 is not sufficient to estimate the snow erosion flux that results from drag partitioning at the surface because C DN10 includes the contribution of the sas-trugi form drag. |
author2 |
Université Grenoble Alpes 2016-2019 (UGA 2016-2019 ) Erosion torrentielle neige et avalanches (UR ETGR (ETNA)) Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA) |
format |
Article in Journal/Newspaper |
author |
Amory, Charles Naaim-Bouvet, F. Gallée, H Vignon, E |
author_facet |
Amory, Charles Naaim-Bouvet, F. Gallée, H Vignon, E |
author_sort |
Amory, Charles |
title |
Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi |
title_short |
Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi |
title_full |
Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi |
title_fullStr |
Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi |
title_full_unstemmed |
Brief communication: Two well-marked cases of aerodynamic adjustment of sastrugi |
title_sort |
brief communication: two well-marked cases of aerodynamic adjustment of sastrugi |
publisher |
HAL CCSD |
publishDate |
2016 |
url |
https://insu.hal.science/insu-01388863 https://insu.hal.science/insu-01388863/document https://insu.hal.science/insu-01388863/file/CRYOSPHERE%20-%20Brief%20communication%20Two%20well-marked%20cases%20of%20aerodynamic%20adjustment%20of%20sastrugi.pdf https://doi.org/10.5194/tc-10-743-2016 |
long_lat |
ENVELOPE(163.683,163.683,-74.617,-74.617) |
geographic |
Austral East Antarctica Sastrugi |
geographic_facet |
Austral East Antarctica Sastrugi |
genre |
Antarc* Antarctica East Antarctica The Cryosphere |
genre_facet |
Antarc* Antarctica East Antarctica The Cryosphere |
op_source |
ISSN: 1994-0424 EISSN: 1994-0416 The Cryosphere https://insu.hal.science/insu-01388863 The Cryosphere, 2016, 10 (2), pp.743 - 750. ⟨10.5194/tc-10-743-2016⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-10-743-2016 insu-01388863 https://insu.hal.science/insu-01388863 https://insu.hal.science/insu-01388863/document https://insu.hal.science/insu-01388863/file/CRYOSPHERE%20-%20Brief%20communication%20Two%20well-marked%20cases%20of%20aerodynamic%20adjustment%20of%20sastrugi.pdf doi:10.5194/tc-10-743-2016 IRSTEA: PUB00054166 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/tc-10-743-2016 |
container_title |
The Cryosphere |
container_volume |
10 |
container_issue |
2 |
container_start_page |
743 |
op_container_end_page |
750 |
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1796300238317682688 |