Multi-tracer study of gas trapping in an East Antarctic ice core
We study a firn and ice core drilled at the new “Lock-In” site in East Antarctica, located 136 km away from Concordia station towards Dumont d'Urville. High-resolution chemical and physical measurements were performed on the core, with a particular focus on the trapping zone of the firn where a...
Published in: | The Cryosphere |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Copernicus Publications
2019
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Online Access: | https://doi.org/10.5194/tc-13-3383-2019 https://www.the-cryosphere.net/13/3383/2019/tc-13-3383-2019.pdf https://doaj.org/article/cc695892c9c649c4b1dd5d69aff6060b |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:cc695892c9c649c4b1dd5d69aff6060b 2023-05-15T13:47:17+02:00 Multi-tracer study of gas trapping in an East Antarctic ice core K. Fourteau P. Martinerie X. Faïn C. F. Schaller R. J. Tuckwell H. Löwe L. Arnaud O. Magand E. R. Thomas J. Freitag R. Mulvaney M. Schneebeli V. Ya. Lipenkov 2019-12-01 https://doi.org/10.5194/tc-13-3383-2019 https://www.the-cryosphere.net/13/3383/2019/tc-13-3383-2019.pdf https://doaj.org/article/cc695892c9c649c4b1dd5d69aff6060b en eng Copernicus Publications doi:10.5194/tc-13-3383-2019 1994-0416 1994-0424 https://www.the-cryosphere.net/13/3383/2019/tc-13-3383-2019.pdf https://doaj.org/article/cc695892c9c649c4b1dd5d69aff6060b undefined The Cryosphere, Vol 13, Pp 3383-3403 (2019) geo envir Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2019 fttriple https://doi.org/10.5194/tc-13-3383-2019 2023-01-22T19:28:48Z We study a firn and ice core drilled at the new “Lock-In” site in East Antarctica, located 136 km away from Concordia station towards Dumont d'Urville. High-resolution chemical and physical measurements were performed on the core, with a particular focus on the trapping zone of the firn where air bubbles are formed. We measured the air content in the ice, closed and open porous volumes in the firn, firn density, firn liquid conductivity, major ion concentrations, and methane concentrations in the ice. The closed and open porosity volumes of firn samples were obtained using the two independent methods of pycnometry and tomography, which yield similar results. The measured increase in the closed porosity with density is used to estimate the air content trapped in the ice with the aid of a simple gas-trapping model. Results show a discrepancy, with the model trapping too much air. Experimental errors have been considered but do not explain the discrepancy between the model and the observations. The model and data can be reconciled with the introduction of a reduced compression of the closed porosity compared to the open porosity. Yet, it is not clear if this limited compression of closed pores is the actual mechanism responsible for the low amount of air in the ice. High-resolution density measurements reveal the presence of strong layering, manifesting itself as centimeter-scale variations. Despite this heterogeneous stratification, all layers, including the ones that are especially dense or less dense compared to their surroundings, display similar pore morphology and closed porosity as a function of density. This implies that all layers close in a similar way, even though some close in advance or later compared to the bulk firn. Investigation of the chemistry data suggests that in the trapping zone, the observed stratification is partly related to the presence of chemical impurities. Article in Journal/Newspaper Antarc* Antarctic Antarctica East Antarctica ice core The Cryosphere Unknown Antarctic East Antarctica Dumont d'Urville ENVELOPE(140.017,140.017,-66.667,-66.667) Dumont-d'Urville ENVELOPE(140.013,140.013,-66.667,-66.667) Concordia Station ENVELOPE(123.333,123.333,-75.100,-75.100) The Cryosphere 13 12 3383 3403 |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English |
topic |
geo envir |
spellingShingle |
geo envir K. Fourteau P. Martinerie X. Faïn C. F. Schaller R. J. Tuckwell H. Löwe L. Arnaud O. Magand E. R. Thomas J. Freitag R. Mulvaney M. Schneebeli V. Ya. Lipenkov Multi-tracer study of gas trapping in an East Antarctic ice core |
topic_facet |
geo envir |
description |
We study a firn and ice core drilled at the new “Lock-In” site in East Antarctica, located 136 km away from Concordia station towards Dumont d'Urville. High-resolution chemical and physical measurements were performed on the core, with a particular focus on the trapping zone of the firn where air bubbles are formed. We measured the air content in the ice, closed and open porous volumes in the firn, firn density, firn liquid conductivity, major ion concentrations, and methane concentrations in the ice. The closed and open porosity volumes of firn samples were obtained using the two independent methods of pycnometry and tomography, which yield similar results. The measured increase in the closed porosity with density is used to estimate the air content trapped in the ice with the aid of a simple gas-trapping model. Results show a discrepancy, with the model trapping too much air. Experimental errors have been considered but do not explain the discrepancy between the model and the observations. The model and data can be reconciled with the introduction of a reduced compression of the closed porosity compared to the open porosity. Yet, it is not clear if this limited compression of closed pores is the actual mechanism responsible for the low amount of air in the ice. High-resolution density measurements reveal the presence of strong layering, manifesting itself as centimeter-scale variations. Despite this heterogeneous stratification, all layers, including the ones that are especially dense or less dense compared to their surroundings, display similar pore morphology and closed porosity as a function of density. This implies that all layers close in a similar way, even though some close in advance or later compared to the bulk firn. Investigation of the chemistry data suggests that in the trapping zone, the observed stratification is partly related to the presence of chemical impurities. |
format |
Article in Journal/Newspaper |
author |
K. Fourteau P. Martinerie X. Faïn C. F. Schaller R. J. Tuckwell H. Löwe L. Arnaud O. Magand E. R. Thomas J. Freitag R. Mulvaney M. Schneebeli V. Ya. Lipenkov |
author_facet |
K. Fourteau P. Martinerie X. Faïn C. F. Schaller R. J. Tuckwell H. Löwe L. Arnaud O. Magand E. R. Thomas J. Freitag R. Mulvaney M. Schneebeli V. Ya. Lipenkov |
author_sort |
K. Fourteau |
title |
Multi-tracer study of gas trapping in an East Antarctic ice core |
title_short |
Multi-tracer study of gas trapping in an East Antarctic ice core |
title_full |
Multi-tracer study of gas trapping in an East Antarctic ice core |
title_fullStr |
Multi-tracer study of gas trapping in an East Antarctic ice core |
title_full_unstemmed |
Multi-tracer study of gas trapping in an East Antarctic ice core |
title_sort |
multi-tracer study of gas trapping in an east antarctic ice core |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-13-3383-2019 https://www.the-cryosphere.net/13/3383/2019/tc-13-3383-2019.pdf https://doaj.org/article/cc695892c9c649c4b1dd5d69aff6060b |
long_lat |
ENVELOPE(140.017,140.017,-66.667,-66.667) ENVELOPE(140.013,140.013,-66.667,-66.667) ENVELOPE(123.333,123.333,-75.100,-75.100) |
geographic |
Antarctic East Antarctica Dumont d'Urville Dumont-d'Urville Concordia Station |
geographic_facet |
Antarctic East Antarctica Dumont d'Urville Dumont-d'Urville Concordia Station |
genre |
Antarc* Antarctic Antarctica East Antarctica ice core The Cryosphere |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica ice core The Cryosphere |
op_source |
The Cryosphere, Vol 13, Pp 3383-3403 (2019) |
op_relation |
doi:10.5194/tc-13-3383-2019 1994-0416 1994-0424 https://www.the-cryosphere.net/13/3383/2019/tc-13-3383-2019.pdf https://doaj.org/article/cc695892c9c649c4b1dd5d69aff6060b |
op_rights |
undefined |
op_doi |
https://doi.org/10.5194/tc-13-3383-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
container_issue |
12 |
container_start_page |
3383 |
op_container_end_page |
3403 |
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1766246856726151168 |