Detecting supraglacial debris thickness with GPR under suboptimal conditions
The thickness of a supraglacial layer is critical to the magnitude and time frame of glacier melt. Field-based, short pulse, ground-penetrating radar (GPR) has successfully measured debris thickness during a glacier's melt season, when there is a strong return from the ice–debris interface, but...
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Cambridge University Press (CUP)
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crcambridgeupr:10.1017/jog.2021.59 2024-09-15T18:15:37+00:00 Detecting supraglacial debris thickness with GPR under suboptimal conditions Giese, Alexandra Arcone, Steven Hawley, Robert Lewis, Gabriel Wagnon, Patrick 2021 http://dx.doi.org/10.1017/jog.2021.59 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000599 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 67, issue 266, page 1108-1120 ISSN 0022-1430 1727-5652 journal-article 2021 crcambridgeupr https://doi.org/10.1017/jog.2021.59 2024-08-07T04:03:38Z The thickness of a supraglacial layer is critical to the magnitude and time frame of glacier melt. Field-based, short pulse, ground-penetrating radar (GPR) has successfully measured debris thickness during a glacier's melt season, when there is a strong return from the ice–debris interface, but profiling with GPR in the absence of a highly reflective ice interface has not been explored. We investigated the performance of 960 MHz signals over 2 km of transects on Changri Nup Glacier, Nepal, during the post-monsoon. We also performed laboratory experiments to interpret the field data and investigate electromagnetic wave propagation into dry rocky debris. Laboratory tests confirmed wave penetration into the glacier ice and suggest that the ice–debris interface return was missing in field data because of a weak dielectric contrast between solid ice and porous dry debris. We developed a new method to estimate debris thicknesses by applying a statistical approach to volumetric backscatter, and our backscatter-based calculated thickness retrievals gave reasonable agreement with debris depths measured manually in the field (10–40 cm). We conclude that, when melt season profiling is not an option, a remote system near 1 GHz could allow dry debris thickness to be estimated based on volumetric backscatter. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Journal of Glaciology 1 13 |
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Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
The thickness of a supraglacial layer is critical to the magnitude and time frame of glacier melt. Field-based, short pulse, ground-penetrating radar (GPR) has successfully measured debris thickness during a glacier's melt season, when there is a strong return from the ice–debris interface, but profiling with GPR in the absence of a highly reflective ice interface has not been explored. We investigated the performance of 960 MHz signals over 2 km of transects on Changri Nup Glacier, Nepal, during the post-monsoon. We also performed laboratory experiments to interpret the field data and investigate electromagnetic wave propagation into dry rocky debris. Laboratory tests confirmed wave penetration into the glacier ice and suggest that the ice–debris interface return was missing in field data because of a weak dielectric contrast between solid ice and porous dry debris. We developed a new method to estimate debris thicknesses by applying a statistical approach to volumetric backscatter, and our backscatter-based calculated thickness retrievals gave reasonable agreement with debris depths measured manually in the field (10–40 cm). We conclude that, when melt season profiling is not an option, a remote system near 1 GHz could allow dry debris thickness to be estimated based on volumetric backscatter. |
format |
Article in Journal/Newspaper |
author |
Giese, Alexandra Arcone, Steven Hawley, Robert Lewis, Gabriel Wagnon, Patrick |
spellingShingle |
Giese, Alexandra Arcone, Steven Hawley, Robert Lewis, Gabriel Wagnon, Patrick Detecting supraglacial debris thickness with GPR under suboptimal conditions |
author_facet |
Giese, Alexandra Arcone, Steven Hawley, Robert Lewis, Gabriel Wagnon, Patrick |
author_sort |
Giese, Alexandra |
title |
Detecting supraglacial debris thickness with GPR under suboptimal conditions |
title_short |
Detecting supraglacial debris thickness with GPR under suboptimal conditions |
title_full |
Detecting supraglacial debris thickness with GPR under suboptimal conditions |
title_fullStr |
Detecting supraglacial debris thickness with GPR under suboptimal conditions |
title_full_unstemmed |
Detecting supraglacial debris thickness with GPR under suboptimal conditions |
title_sort |
detecting supraglacial debris thickness with gpr under suboptimal conditions |
publisher |
Cambridge University Press (CUP) |
publishDate |
2021 |
url |
http://dx.doi.org/10.1017/jog.2021.59 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143021000599 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 67, issue 266, page 1108-1120 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2021.59 |
container_title |
Journal of Glaciology |
container_start_page |
1 |
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13 |
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1810453491872694272 |