On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core
International audience We compare a variety of methods for estimating the gas/ice depth offset (Delta depth) at EPICA Dome C (EDC, East Antarctica). (1) Purely based on modelling efforts, Delta depth can be estimated combining a firn densification with an ice flow model. (2) The diffusive column hei...
Published in: | Climate of the Past |
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Main Authors: | , , , , , , , , |
Other Authors: | , , , , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2013
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Subjects: | |
Online Access: | https://insu.hal.science/insu-00843989 https://insu.hal.science/insu-00843989/document https://insu.hal.science/insu-00843989/file/cp-8-1239-2012.pdf https://doi.org/10.5194/cp-8-1239-2012 |
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ftunifranchecom:oai:HAL:insu-00843989v1 |
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Open Polar |
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Université de Franche-Comté (UFC): HAL |
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ftunifranchecom |
language |
English |
topic |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
spellingShingle |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences Parrenin, F. Barker, S. Blunier, T. Chappellaz, J. Jouzel, Jean Landais, Amaelle Masson-Delmotte, Valérie Schwander, J. Veres, D. On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core |
topic_facet |
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences |
description |
International audience We compare a variety of methods for estimating the gas/ice depth offset (Delta depth) at EPICA Dome C (EDC, East Antarctica). (1) Purely based on modelling efforts, Delta depth can be estimated combining a firn densification with an ice flow model. (2) The diffusive column height can be estimated from δ15N and converted to Delta depth using an ice flow model and assumptions about past average firn density and thickness of the convective zone. (3) Ice and gas synchronisation of the EDC ice core to the GRIP, EDML and TALDICE ice cores shifts the ice/gas offset problem into higher accumulation ice cores where it can be more accurately evaluated. (4) Finally, the bipolar seesaw hypothesis allows us to synchronise the ice isotopic record with the gas CH4 record, the later being taken as a proxy of Greenland temperature. The general agreement of method 4 with methods 2 and 3 confirms that the bipolar seesaw antiphase happened during the last 140 kyr. Applying method 4 to the deeper section of the EDC core confirms that the ice flow is complex and can help to improve our reconstruction of the thinning function and thus, of the EDC age scale. We confirm that method 1 overestimates the glacial Delta depth at EDC and we suggest that it is due to an overestimation of the glacial lock-in depth (LID) by the firn densification model. In contrast, we find that method 1 very likely underestimates Delta depth during Termination II, due either to an underestimated thinning function or to an underestimated LID. Finally, method 2 gives estimates within a few metres of methods 3 and 4 during the last deglacial warming, suggesting that the convective zone at Dome C cannot have been very large at this time, if it existed at all. |
author2 |
Laboratoire de glaciologie et géophysique de l'environnement (LGGE) 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 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)-Centre National de la Recherche Scientifique (CNRS) Laboratoire Chrono-environnement (UMR 6249) (LCE) Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) Université Bourgogne Franche-Comté COMUE (UBFC)-Université Bourgogne Franche-Comté COMUE (UBFC) School of Earth and Ocean Sciences Cardiff Cardiff University Centre for Ice and Climate Copenhagen Niels Bohr Institute Copenhagen (NBI) Faculty of Science Copenhagen University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH)-Faculty of Science Copenhagen University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) Glaces et Continents, Climats et Isotopes Stables (GLACCIOS) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Physics Institute Bern Universität Bern / University of Bern (UNIBE) Institute of Speleology Romanian Academy |
format |
Article in Journal/Newspaper |
author |
Parrenin, F. Barker, S. Blunier, T. Chappellaz, J. Jouzel, Jean Landais, Amaelle Masson-Delmotte, Valérie Schwander, J. Veres, D. |
author_facet |
Parrenin, F. Barker, S. Blunier, T. Chappellaz, J. Jouzel, Jean Landais, Amaelle Masson-Delmotte, Valérie Schwander, J. Veres, D. |
author_sort |
Parrenin, F. |
title |
On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core |
title_short |
On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core |
title_full |
On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core |
title_fullStr |
On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core |
title_full_unstemmed |
On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core |
title_sort |
on the gas-ice depth difference (delta depth) along the epica dome c ice core |
publisher |
HAL CCSD |
publishDate |
2013 |
url |
https://insu.hal.science/insu-00843989 https://insu.hal.science/insu-00843989/document https://insu.hal.science/insu-00843989/file/cp-8-1239-2012.pdf https://doi.org/10.5194/cp-8-1239-2012 |
genre |
Antarc* Antarctica East Antarctica EPICA Greenland GRIP ice core |
genre_facet |
Antarc* Antarctica East Antarctica EPICA Greenland GRIP ice core |
op_source |
ISSN: 1814-9324 EISSN: 1814-9332 Climate of the Past https://insu.hal.science/insu-00843989 Climate of the Past, 2013, 8, pp.1239- 1255. ⟨10.5194/cp-8-1239-2012⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/cp-8-1239-2012 insu-00843989 https://insu.hal.science/insu-00843989 https://insu.hal.science/insu-00843989/document https://insu.hal.science/insu-00843989/file/cp-8-1239-2012.pdf doi:10.5194/cp-8-1239-2012 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/cp-8-1239-2012 |
container_title |
Climate of the Past |
container_volume |
8 |
container_issue |
4 |
container_start_page |
1239 |
op_container_end_page |
1255 |
_version_ |
1797573330590498816 |
spelling |
ftunifranchecom:oai:HAL:insu-00843989v1 2024-04-28T08:01:41+00:00 On the gas-ice depth difference (Delta depth) along the EPICA Dome C ice core Parrenin, F. Barker, S. Blunier, T. Chappellaz, J. Jouzel, Jean Landais, Amaelle Masson-Delmotte, Valérie Schwander, J. Veres, D. Laboratoire de glaciologie et géophysique de l'environnement (LGGE) 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 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)-Centre National de la Recherche Scientifique (CNRS) Laboratoire Chrono-environnement (UMR 6249) (LCE) Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC) Université Bourgogne Franche-Comté COMUE (UBFC)-Université Bourgogne Franche-Comté COMUE (UBFC) School of Earth and Ocean Sciences Cardiff Cardiff University Centre for Ice and Climate Copenhagen Niels Bohr Institute Copenhagen (NBI) Faculty of Science Copenhagen University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH)-Faculty of Science Copenhagen University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH) Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE) Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA) Glaces et Continents, Climats et Isotopes Stables (GLACCIOS) Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) Physics Institute Bern Universität Bern / University of Bern (UNIBE) Institute of Speleology Romanian Academy 2013-08-02 https://insu.hal.science/insu-00843989 https://insu.hal.science/insu-00843989/document https://insu.hal.science/insu-00843989/file/cp-8-1239-2012.pdf https://doi.org/10.5194/cp-8-1239-2012 en eng HAL CCSD European Geosciences Union (EGU) info:eu-repo/semantics/altIdentifier/doi/10.5194/cp-8-1239-2012 insu-00843989 https://insu.hal.science/insu-00843989 https://insu.hal.science/insu-00843989/document https://insu.hal.science/insu-00843989/file/cp-8-1239-2012.pdf doi:10.5194/cp-8-1239-2012 info:eu-repo/semantics/OpenAccess ISSN: 1814-9324 EISSN: 1814-9332 Climate of the Past https://insu.hal.science/insu-00843989 Climate of the Past, 2013, 8, pp.1239- 1255. ⟨10.5194/cp-8-1239-2012⟩ [SDU.STU]Sciences of the Universe [physics]/Earth Sciences info:eu-repo/semantics/article Journal articles 2013 ftunifranchecom https://doi.org/10.5194/cp-8-1239-2012 2024-04-10T23:44:04Z International audience We compare a variety of methods for estimating the gas/ice depth offset (Delta depth) at EPICA Dome C (EDC, East Antarctica). (1) Purely based on modelling efforts, Delta depth can be estimated combining a firn densification with an ice flow model. (2) The diffusive column height can be estimated from δ15N and converted to Delta depth using an ice flow model and assumptions about past average firn density and thickness of the convective zone. (3) Ice and gas synchronisation of the EDC ice core to the GRIP, EDML and TALDICE ice cores shifts the ice/gas offset problem into higher accumulation ice cores where it can be more accurately evaluated. (4) Finally, the bipolar seesaw hypothesis allows us to synchronise the ice isotopic record with the gas CH4 record, the later being taken as a proxy of Greenland temperature. The general agreement of method 4 with methods 2 and 3 confirms that the bipolar seesaw antiphase happened during the last 140 kyr. Applying method 4 to the deeper section of the EDC core confirms that the ice flow is complex and can help to improve our reconstruction of the thinning function and thus, of the EDC age scale. We confirm that method 1 overestimates the glacial Delta depth at EDC and we suggest that it is due to an overestimation of the glacial lock-in depth (LID) by the firn densification model. In contrast, we find that method 1 very likely underestimates Delta depth during Termination II, due either to an underestimated thinning function or to an underestimated LID. Finally, method 2 gives estimates within a few metres of methods 3 and 4 during the last deglacial warming, suggesting that the convective zone at Dome C cannot have been very large at this time, if it existed at all. Article in Journal/Newspaper Antarc* Antarctica East Antarctica EPICA Greenland GRIP ice core Université de Franche-Comté (UFC): HAL Climate of the Past 8 4 1239 1255 |