Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration
The bulk crystal orientation in ice influences the flow of glaciers and ice streams. The ice c -axes fabric is most reliably derived from ice cores. Because these are sparse, the spatial and vertical distribution of the fabric in the Greenland and Antarctic ice sheets is largely unknown. In recent y...
Published in: | The Cryosphere |
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ftcopernicus:oai:publications.copernicus.org:tc106932 2023-05-15T13:31:14+02:00 Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration Zeising, Ole Gerber, Tamara Annina Eisen, Olaf Ershadi, M. Reza Stoll, Nicolas Weikusat, Ilka Humbert, Angelika 2023-03-06 application/pdf https://doi.org/10.5194/tc-17-1097-2023 https://tc.copernicus.org/articles/17/1097/2023/ eng eng doi:10.5194/tc-17-1097-2023 https://tc.copernicus.org/articles/17/1097/2023/ eISSN: 1994-0424 Text 2023 ftcopernicus https://doi.org/10.5194/tc-17-1097-2023 2023-03-13T17:23:11Z The bulk crystal orientation in ice influences the flow of glaciers and ice streams. The ice c -axes fabric is most reliably derived from ice cores. Because these are sparse, the spatial and vertical distribution of the fabric in the Greenland and Antarctic ice sheets is largely unknown. In recent years, methods have been developed to determine fabric characteristics from polarimetric radar measurements. The aim of this paper is to present an improved method to infer the horizontal fabric asymmetry by precisely determining the travel-time difference using co-polarised phase-sensitive radar data. We applied this method to six radar measurements from the East Greenland Ice-core Project (EastGRIP) drill site on Greenland's largest ice stream to give a proof of concept by comparing the results with the horizontal asymmetry of the bulk crystal anisotropy derived from the ice core. This comparison shows an excellent agreement, which is a large improvement compared to previously used methods. Our approach is particularly useful for determining the vertical profile of the fabric asymmetry in higher resolution and over larger depths than was achievable with previous methods, especially in regions with strong asymmetry. Text Antarc* Antarctic East Greenland East Greenland Ice-core Project Greenland Greenland ice core Greenland Ice core Project ice core Copernicus Publications: E-Journals Antarctic Greenland The Cryosphere 17 3 1097 1105 |
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Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
The bulk crystal orientation in ice influences the flow of glaciers and ice streams. The ice c -axes fabric is most reliably derived from ice cores. Because these are sparse, the spatial and vertical distribution of the fabric in the Greenland and Antarctic ice sheets is largely unknown. In recent years, methods have been developed to determine fabric characteristics from polarimetric radar measurements. The aim of this paper is to present an improved method to infer the horizontal fabric asymmetry by precisely determining the travel-time difference using co-polarised phase-sensitive radar data. We applied this method to six radar measurements from the East Greenland Ice-core Project (EastGRIP) drill site on Greenland's largest ice stream to give a proof of concept by comparing the results with the horizontal asymmetry of the bulk crystal anisotropy derived from the ice core. This comparison shows an excellent agreement, which is a large improvement compared to previously used methods. Our approach is particularly useful for determining the vertical profile of the fabric asymmetry in higher resolution and over larger depths than was achievable with previous methods, especially in regions with strong asymmetry. |
format |
Text |
author |
Zeising, Ole Gerber, Tamara Annina Eisen, Olaf Ershadi, M. Reza Stoll, Nicolas Weikusat, Ilka Humbert, Angelika |
spellingShingle |
Zeising, Ole Gerber, Tamara Annina Eisen, Olaf Ershadi, M. Reza Stoll, Nicolas Weikusat, Ilka Humbert, Angelika Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration |
author_facet |
Zeising, Ole Gerber, Tamara Annina Eisen, Olaf Ershadi, M. Reza Stoll, Nicolas Weikusat, Ilka Humbert, Angelika |
author_sort |
Zeising, Ole |
title |
Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration |
title_short |
Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration |
title_full |
Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration |
title_fullStr |
Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration |
title_full_unstemmed |
Improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration |
title_sort |
improved estimation of the bulk ice crystal fabric asymmetry from polarimetric phase co-registration |
publishDate |
2023 |
url |
https://doi.org/10.5194/tc-17-1097-2023 https://tc.copernicus.org/articles/17/1097/2023/ |
geographic |
Antarctic Greenland |
geographic_facet |
Antarctic Greenland |
genre |
Antarc* Antarctic East Greenland East Greenland Ice-core Project Greenland Greenland ice core Greenland Ice core Project ice core |
genre_facet |
Antarc* Antarctic East Greenland East Greenland Ice-core Project Greenland Greenland ice core Greenland Ice core Project ice core |
op_source |
eISSN: 1994-0424 |
op_relation |
doi:10.5194/tc-17-1097-2023 https://tc.copernicus.org/articles/17/1097/2023/ |
op_doi |
https://doi.org/10.5194/tc-17-1097-2023 |
container_title |
The Cryosphere |
container_volume |
17 |
container_issue |
3 |
container_start_page |
1097 |
op_container_end_page |
1105 |
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1766016852208648192 |