Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum
International audience For the Last Glacial Maximum, (LGM; 21 000 BP), simulations using atmospheric general-circulation models (AGCMs) are very sensitive to the prescribed boundary conditions. Most of the recent numerical experiments have used the CLIMAP (1981) data set for ice-sheet topography, se...
Published in: | Annals of Glaciology |
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ftccsdartic:oai:HAL:hal-03011873v1 2023-05-15T13:29:17+02:00 Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum Ramstein, Gilles Joussaume, Sylvie Laboratoire de Modélisation du Climat et de l'Environnement (LMCE) 1995 https://hal.archives-ouvertes.fr/hal-03011873 https://hal.archives-ouvertes.fr/hal-03011873/document https://hal.archives-ouvertes.fr/hal-03011873/file/ag3.pdf https://doi.org/10.3189/S0260305500016049 en eng HAL CCSD International Glaciological Society info:eu-repo/semantics/altIdentifier/doi/10.3189/S0260305500016049 hal-03011873 https://hal.archives-ouvertes.fr/hal-03011873 https://hal.archives-ouvertes.fr/hal-03011873/document https://hal.archives-ouvertes.fr/hal-03011873/file/ag3.pdf doi:10.3189/S0260305500016049 info:eu-repo/semantics/OpenAccess ISSN: 0260-3055 Annals of Glaciology https://hal.archives-ouvertes.fr/hal-03011873 Annals of Glaciology, International Glaciological Society, 1995, 21, pp.343-347. ⟨10.3189/S0260305500016049⟩ [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment info:eu-repo/semantics/article Journal articles 1995 ftccsdartic https://doi.org/10.3189/S0260305500016049 2021-09-11T22:45:04Z International audience For the Last Glacial Maximum, (LGM; 21 000 BP), simulations using atmospheric general-circulation models (AGCMs) are very sensitive to the prescribed boundary conditions. Most of the recent numerical experiments have used the CLIMAP (1981) data set for ice-sheet topography, sea-ice extent and sea surface temperatures (SSTs). To demonstrate the impact of ice-sheet reconstruction on the LGM climate, we performed two simulations: one using CLIMAP (1981) ice-sheet topography, the other using the new reconstruction provided by Peltier. We show that, although the geographical structure of the annually averaged temperature is not modified, there are important seasonal and regional impacts on the temperature distribution. In a second step, to analyze the effects of cooler SSTs and sea-ice extent, we performed a simulation using CLIMAP (1981) for the ice-sheet topography, but with present SSTs. We find that the cooling due to ice sheets for the LGM climate is one-third of the global annually averaged cooling, and dial the southward shift of the North Atlantic low in winter is not due to sea-ice extent, but is an orographic effect due to the Laurenride ice sheet. This set of sensitivity experiments allows us also to discriminate between thermal and orographic forcings and to show the impact of the ice-sheet topography and cooler SSTs on the pattern of planetary waves during the LGM climate. Article in Journal/Newspaper Annals of Glaciology Ice Sheet North Atlantic Sea ice Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Peltier ENVELOPE(-63.495,-63.495,-64.854,-64.854) Annals of Glaciology 21 343 347 |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment |
spellingShingle |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment Ramstein, Gilles Joussaume, Sylvie Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum |
topic_facet |
[SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment |
description |
International audience For the Last Glacial Maximum, (LGM; 21 000 BP), simulations using atmospheric general-circulation models (AGCMs) are very sensitive to the prescribed boundary conditions. Most of the recent numerical experiments have used the CLIMAP (1981) data set for ice-sheet topography, sea-ice extent and sea surface temperatures (SSTs). To demonstrate the impact of ice-sheet reconstruction on the LGM climate, we performed two simulations: one using CLIMAP (1981) ice-sheet topography, the other using the new reconstruction provided by Peltier. We show that, although the geographical structure of the annually averaged temperature is not modified, there are important seasonal and regional impacts on the temperature distribution. In a second step, to analyze the effects of cooler SSTs and sea-ice extent, we performed a simulation using CLIMAP (1981) for the ice-sheet topography, but with present SSTs. We find that the cooling due to ice sheets for the LGM climate is one-third of the global annually averaged cooling, and dial the southward shift of the North Atlantic low in winter is not due to sea-ice extent, but is an orographic effect due to the Laurenride ice sheet. This set of sensitivity experiments allows us also to discriminate between thermal and orographic forcings and to show the impact of the ice-sheet topography and cooler SSTs on the pattern of planetary waves during the LGM climate. |
author2 |
Laboratoire de Modélisation du Climat et de l'Environnement (LMCE) |
format |
Article in Journal/Newspaper |
author |
Ramstein, Gilles Joussaume, Sylvie |
author_facet |
Ramstein, Gilles Joussaume, Sylvie |
author_sort |
Ramstein, Gilles |
title |
Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum |
title_short |
Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum |
title_full |
Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum |
title_fullStr |
Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum |
title_full_unstemmed |
Sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the Last Glacial Maximum |
title_sort |
sensitivity experiments to sea surface temperatures, sea-ice extent and ice-sheet reconstruction, for the last glacial maximum |
publisher |
HAL CCSD |
publishDate |
1995 |
url |
https://hal.archives-ouvertes.fr/hal-03011873 https://hal.archives-ouvertes.fr/hal-03011873/document https://hal.archives-ouvertes.fr/hal-03011873/file/ag3.pdf https://doi.org/10.3189/S0260305500016049 |
long_lat |
ENVELOPE(-63.495,-63.495,-64.854,-64.854) |
geographic |
Peltier |
geographic_facet |
Peltier |
genre |
Annals of Glaciology Ice Sheet North Atlantic Sea ice |
genre_facet |
Annals of Glaciology Ice Sheet North Atlantic Sea ice |
op_source |
ISSN: 0260-3055 Annals of Glaciology https://hal.archives-ouvertes.fr/hal-03011873 Annals of Glaciology, International Glaciological Society, 1995, 21, pp.343-347. ⟨10.3189/S0260305500016049⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.3189/S0260305500016049 hal-03011873 https://hal.archives-ouvertes.fr/hal-03011873 https://hal.archives-ouvertes.fr/hal-03011873/document https://hal.archives-ouvertes.fr/hal-03011873/file/ag3.pdf doi:10.3189/S0260305500016049 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.3189/S0260305500016049 |
container_title |
Annals of Glaciology |
container_volume |
21 |
container_start_page |
343 |
op_container_end_page |
347 |
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1765999722530603008 |