Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes
The Antarctic Surface Mass Balance (SMB, i.e. the snow accumulation from which we subtract ablation by sublimation, run-off or erosion) is a major yet badly known contribution to changes in the present-day sea level. Water storage by snow accumulation on the Antarctic continent is expected to increa...
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Other Authors: | , , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | French |
Published: |
HAL CCSD
2012
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Online Access: | https://tel.archives-ouvertes.fr/tel-00877881 https://tel.archives-ouvertes.fr/tel-00877881/document https://tel.archives-ouvertes.fr/tel-00877881/file/Agosta_These.pdf |
id |
ftccsdartic:oai:HAL:tel-00877881v1 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
French |
topic |
Downscaling Polar Climate Climate modelling Surface Energy balance Surface Mass Balance Antarctic Antarctique Bilan de Masse de Surface Bilan d'Energie de Surface Modèle de climat Climat polaire Régionalisation [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
Downscaling Polar Climate Climate modelling Surface Energy balance Surface Mass Balance Antarctic Antarctique Bilan de Masse de Surface Bilan d'Energie de Surface Modèle de climat Climat polaire Régionalisation [SDU.STU]Sciences of the Universe [physics]/Earth Sciences Agosta, Cécile Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes |
topic_facet |
Downscaling Polar Climate Climate modelling Surface Energy balance Surface Mass Balance Antarctic Antarctique Bilan de Masse de Surface Bilan d'Energie de Surface Modèle de climat Climat polaire Régionalisation [SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
The Antarctic Surface Mass Balance (SMB, i.e. the snow accumulation from which we subtract ablation by sublimation, run-off or erosion) is a major yet badly known contribution to changes in the present-day sea level. Water storage by snow accumulation on the Antarctic continent is expected to increase in the 21st century, which would moderate the rise in sea level and impact the ice dynamic response of the ice sheet. Three-quarters of the Antarctic SMB are concentrated below 2000 m above sea level whereas this area represents only 40% of the grounded ice sheet area. Orographic precipitation is a major contributor to snow accumulation in this region, which is why a better estimation of this term is important. The representation of this process by models depends to a great extent on the resolution of the model, since precipitation amounts depend on the ice sheet slopes. Sublimation and snowmelt also depend on elevation, and although they are presently minor contributors to the Antarctic SMB, their role is expected to become more important in the coming centuries. Global and regional atmospheric climate models are unable to achieve a 40-km resolution over Antarctica at a century time scale, due to their computing cost. At this resolution, the Antarctic coastal area is still badly represented. This is why we developed the downscaling model SMHiL (Surface mass balance high-resolution downscaling) to estimate the Antarctic SMB components at a high resolution (~15 km) from large-scale atmospheric forcings. We computed the impact of the high-resolution topography on orographic precipitation amounts and the boundary layer processes that lead to sublimation, melting and refreezing. SMHiL has been validated for the present period with a dataset composed of more than 2700 quality-controlled observations. However, very few of these observations are representative of the Antarctic coastal area. In this context, we show that the GLACIOCLIM-SAMBA stake lines located on the ice sheet coast-to-plateau area is an appropriate ... |
author2 |
Laboratoire de glaciologie et géophysique de l'environnement (LGGE) Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS) Université de Grenoble Christophe Genthon Vincent Favier |
format |
Doctoral or Postdoctoral Thesis |
author |
Agosta, Cécile |
author_facet |
Agosta, Cécile |
author_sort |
Agosta, Cécile |
title |
Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes |
title_short |
Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes |
title_full |
Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes |
title_fullStr |
Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes |
title_full_unstemmed |
Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes |
title_sort |
evolution of antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes |
publisher |
HAL CCSD |
publishDate |
2012 |
url |
https://tel.archives-ouvertes.fr/tel-00877881 https://tel.archives-ouvertes.fr/tel-00877881/document https://tel.archives-ouvertes.fr/tel-00877881/file/Agosta_These.pdf |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Antarctica Antarctique* Ice Sheet |
genre_facet |
Antarc* Antarctic Antarctica Antarctique* Ice Sheet |
op_source |
https://tel.archives-ouvertes.fr/tel-00877881 Sciences de la Terre. Université de Grenoble, 2012. Français. ⟨NNT : 2012GRENU023⟩ |
op_relation |
NNT: 2012GRENU023 tel-00877881 https://tel.archives-ouvertes.fr/tel-00877881 https://tel.archives-ouvertes.fr/tel-00877881/document https://tel.archives-ouvertes.fr/tel-00877881/file/Agosta_These.pdf |
op_rights |
info:eu-repo/semantics/OpenAccess |
_version_ |
1766253501075161088 |
spelling |
ftccsdartic:oai:HAL:tel-00877881v1 2023-05-15T13:50:26+02:00 Evolution of Antarctic surface mass balance by high-resolution downscaling and impact on sea-level changes Evolution du bilan de masse de surface Antarctique par régionalisation physique et contribution aux variations du niveau des mers Agosta, Cécile Laboratoire de glaciologie et géophysique de l'environnement (LGGE) Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS) Université de Grenoble Christophe Genthon Vincent Favier 2012-06-15 https://tel.archives-ouvertes.fr/tel-00877881 https://tel.archives-ouvertes.fr/tel-00877881/document https://tel.archives-ouvertes.fr/tel-00877881/file/Agosta_These.pdf fr fre HAL CCSD NNT: 2012GRENU023 tel-00877881 https://tel.archives-ouvertes.fr/tel-00877881 https://tel.archives-ouvertes.fr/tel-00877881/document https://tel.archives-ouvertes.fr/tel-00877881/file/Agosta_These.pdf info:eu-repo/semantics/OpenAccess https://tel.archives-ouvertes.fr/tel-00877881 Sciences de la Terre. Université de Grenoble, 2012. Français. ⟨NNT : 2012GRENU023⟩ Downscaling Polar Climate Climate modelling Surface Energy balance Surface Mass Balance Antarctic Antarctique Bilan de Masse de Surface Bilan d'Energie de Surface Modèle de climat Climat polaire Régionalisation [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/doctoralThesis Theses 2012 ftccsdartic 2021-10-24T14:27:23Z The Antarctic Surface Mass Balance (SMB, i.e. the snow accumulation from which we subtract ablation by sublimation, run-off or erosion) is a major yet badly known contribution to changes in the present-day sea level. Water storage by snow accumulation on the Antarctic continent is expected to increase in the 21st century, which would moderate the rise in sea level and impact the ice dynamic response of the ice sheet. Three-quarters of the Antarctic SMB are concentrated below 2000 m above sea level whereas this area represents only 40% of the grounded ice sheet area. Orographic precipitation is a major contributor to snow accumulation in this region, which is why a better estimation of this term is important. The representation of this process by models depends to a great extent on the resolution of the model, since precipitation amounts depend on the ice sheet slopes. Sublimation and snowmelt also depend on elevation, and although they are presently minor contributors to the Antarctic SMB, their role is expected to become more important in the coming centuries. Global and regional atmospheric climate models are unable to achieve a 40-km resolution over Antarctica at a century time scale, due to their computing cost. At this resolution, the Antarctic coastal area is still badly represented. This is why we developed the downscaling model SMHiL (Surface mass balance high-resolution downscaling) to estimate the Antarctic SMB components at a high resolution (~15 km) from large-scale atmospheric forcings. We computed the impact of the high-resolution topography on orographic precipitation amounts and the boundary layer processes that lead to sublimation, melting and refreezing. SMHiL has been validated for the present period with a dataset composed of more than 2700 quality-controlled observations. However, very few of these observations are representative of the Antarctic coastal area. In this context, we show that the GLACIOCLIM-SAMBA stake lines located on the ice sheet coast-to-plateau area is an appropriate ... Doctoral or Postdoctoral Thesis Antarc* Antarctic Antarctica Antarctique* Ice Sheet Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Antarctic The Antarctic |