How old is the ice beneath Dome A, Antarctica?
Chinese scientists will start to drill a deep ice core at Kunlun station near Dome A in the near future. Recent work has predicted that Dome A is a location where ice older than 1 million years can be found. We model flow, temperature and the age of the ice by applying a three-dimensional, thermomec...
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ftdoajarticles:oai:doaj.org/article:297ee06672a745c9accccc35da6b93e0 2023-05-15T13:43:51+02:00 How old is the ice beneath Dome A, Antarctica? B. Sun J. C. Moore T. Zwinger L. Zhao D. Steinhage X. Tang D. Zhang X. Cui C. Martín 2014-06-01T00:00:00Z https://doi.org/10.5194/tc-8-1121-2014 https://doaj.org/article/297ee06672a745c9accccc35da6b93e0 EN eng Copernicus Publications http://www.the-cryosphere.net/8/1121/2014/tc-8-1121-2014.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-8-1121-2014 https://doaj.org/article/297ee06672a745c9accccc35da6b93e0 The Cryosphere, Vol 8, Iss 3, Pp 1121-1128 (2014) Environmental sciences GE1-350 Geology QE1-996.5 article 2014 ftdoajarticles https://doi.org/10.5194/tc-8-1121-2014 2022-12-31T14:46:35Z Chinese scientists will start to drill a deep ice core at Kunlun station near Dome A in the near future. Recent work has predicted that Dome A is a location where ice older than 1 million years can be found. We model flow, temperature and the age of the ice by applying a three-dimensional, thermomechanically coupled full-Stokes model to a 70 × 70 km 2 domain around Kunlun station, using isotropic non-linear rheology and different prescribed anisotropic ice fabrics that vary the evolution from isotropic to single maximum at 1/3 or 2/3 depths. The variation in fabric is about as important as the uncertainties in geothermal heat flux in determining the vertical advection which in consequence controls both the basal temperature and the age profile. We find strongly variable basal ages across the domain since the ice varies greatly in thickness, and any basal melting effectively removes very old ice in the deepest parts of the subglacial valleys. Comparison with dated radar isochrones in the upper one third of the ice sheet cannot sufficiently constrain the age of the deeper ice, with uncertainties as large as 500 000 years in the basal age. We also assess basal age and thermal state sensitivities to geothermal heat flux and surface conditions. Despite expectations of modest changes in surface height over a glacial cycle at Dome A, even small variations in the evolution of surface conditions cause large variation in basal conditions, which is consistent with basal accretion features seen in radar surveys. Article in Journal/Newspaper Antarc* Antarctica ice core Ice Sheet The Cryosphere Directory of Open Access Journals: DOAJ Articles The Cryosphere 8 3 1121 1128 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
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Environmental sciences GE1-350 Geology QE1-996.5 B. Sun J. C. Moore T. Zwinger L. Zhao D. Steinhage X. Tang D. Zhang X. Cui C. Martín How old is the ice beneath Dome A, Antarctica? |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Chinese scientists will start to drill a deep ice core at Kunlun station near Dome A in the near future. Recent work has predicted that Dome A is a location where ice older than 1 million years can be found. We model flow, temperature and the age of the ice by applying a three-dimensional, thermomechanically coupled full-Stokes model to a 70 × 70 km 2 domain around Kunlun station, using isotropic non-linear rheology and different prescribed anisotropic ice fabrics that vary the evolution from isotropic to single maximum at 1/3 or 2/3 depths. The variation in fabric is about as important as the uncertainties in geothermal heat flux in determining the vertical advection which in consequence controls both the basal temperature and the age profile. We find strongly variable basal ages across the domain since the ice varies greatly in thickness, and any basal melting effectively removes very old ice in the deepest parts of the subglacial valleys. Comparison with dated radar isochrones in the upper one third of the ice sheet cannot sufficiently constrain the age of the deeper ice, with uncertainties as large as 500 000 years in the basal age. We also assess basal age and thermal state sensitivities to geothermal heat flux and surface conditions. Despite expectations of modest changes in surface height over a glacial cycle at Dome A, even small variations in the evolution of surface conditions cause large variation in basal conditions, which is consistent with basal accretion features seen in radar surveys. |
format |
Article in Journal/Newspaper |
author |
B. Sun J. C. Moore T. Zwinger L. Zhao D. Steinhage X. Tang D. Zhang X. Cui C. Martín |
author_facet |
B. Sun J. C. Moore T. Zwinger L. Zhao D. Steinhage X. Tang D. Zhang X. Cui C. Martín |
author_sort |
B. Sun |
title |
How old is the ice beneath Dome A, Antarctica? |
title_short |
How old is the ice beneath Dome A, Antarctica? |
title_full |
How old is the ice beneath Dome A, Antarctica? |
title_fullStr |
How old is the ice beneath Dome A, Antarctica? |
title_full_unstemmed |
How old is the ice beneath Dome A, Antarctica? |
title_sort |
how old is the ice beneath dome a, antarctica? |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/tc-8-1121-2014 https://doaj.org/article/297ee06672a745c9accccc35da6b93e0 |
genre |
Antarc* Antarctica ice core Ice Sheet The Cryosphere |
genre_facet |
Antarc* Antarctica ice core Ice Sheet The Cryosphere |
op_source |
The Cryosphere, Vol 8, Iss 3, Pp 1121-1128 (2014) |
op_relation |
http://www.the-cryosphere.net/8/1121/2014/tc-8-1121-2014.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 1994-0416 1994-0424 doi:10.5194/tc-8-1121-2014 https://doaj.org/article/297ee06672a745c9accccc35da6b93e0 |
op_doi |
https://doi.org/10.5194/tc-8-1121-2014 |
container_title |
The Cryosphere |
container_volume |
8 |
container_issue |
3 |
container_start_page |
1121 |
op_container_end_page |
1128 |
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