Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal
ABSTRACT Supraglacial debris thickness is a key control on the surface energy balance of debris-covered glaciers, yet debris thickness measurements are sparse due to difficulties of data collection. Here we use ground-penetrating radar (GPR) to measure debris thickness on the ablation zone of Lirung...
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/jog.2017.18 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143017000181 |
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crcambridgeupr:10.1017/jog.2017.18 2024-06-23T07:54:15+00:00 Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal McCARTHY, MICHAEL PRITCHARD, HAMISH WILLIS, IAN KING, EDWARD 2017 http://dx.doi.org/10.1017/jog.2017.18 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143017000181 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 63, issue 239, page 543-555 ISSN 0022-1430 1727-5652 journal-article 2017 crcambridgeupr https://doi.org/10.1017/jog.2017.18 2024-06-05T04:04:09Z ABSTRACT Supraglacial debris thickness is a key control on the surface energy balance of debris-covered glaciers, yet debris thickness measurements are sparse due to difficulties of data collection. Here we use ground-penetrating radar (GPR) to measure debris thickness on the ablation zone of Lirung Glacier, Nepal. We observe a strong, continuous reflection, which we interpret as the ice surface, through debris layers of 0.1 to at least 2.3 m thick, provided that appropriate acquisition parameters were used while surveying. GPR measurements of debris thickness correlate well with pit measurements of debris thickness ( r = 0.91, RMSE = 0.04 m) and two-way travel times are consistent at tie points ( r = 0.97). 33% of measurements are <0.5 m, so sub-debris melting is likely important in terms of mass loss on the debris-covered tongue and debris thickness is highly variable over small spatial scales (of order 10 m), likely due to local slope processes. GPR can be used to make debris thickness measurements more quickly, over a wider debris thickness range, and at higher spatial resolution than any other means and is therefore a valuable tool with which to map debris thickness distribution on Himalayan glaciers. Article in Journal/Newspaper Journal of Glaciology Cambridge University Press Journal of Glaciology 63 239 543 555 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
ABSTRACT Supraglacial debris thickness is a key control on the surface energy balance of debris-covered glaciers, yet debris thickness measurements are sparse due to difficulties of data collection. Here we use ground-penetrating radar (GPR) to measure debris thickness on the ablation zone of Lirung Glacier, Nepal. We observe a strong, continuous reflection, which we interpret as the ice surface, through debris layers of 0.1 to at least 2.3 m thick, provided that appropriate acquisition parameters were used while surveying. GPR measurements of debris thickness correlate well with pit measurements of debris thickness ( r = 0.91, RMSE = 0.04 m) and two-way travel times are consistent at tie points ( r = 0.97). 33% of measurements are <0.5 m, so sub-debris melting is likely important in terms of mass loss on the debris-covered tongue and debris thickness is highly variable over small spatial scales (of order 10 m), likely due to local slope processes. GPR can be used to make debris thickness measurements more quickly, over a wider debris thickness range, and at higher spatial resolution than any other means and is therefore a valuable tool with which to map debris thickness distribution on Himalayan glaciers. |
format |
Article in Journal/Newspaper |
author |
McCARTHY, MICHAEL PRITCHARD, HAMISH WILLIS, IAN KING, EDWARD |
spellingShingle |
McCARTHY, MICHAEL PRITCHARD, HAMISH WILLIS, IAN KING, EDWARD Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal |
author_facet |
McCARTHY, MICHAEL PRITCHARD, HAMISH WILLIS, IAN KING, EDWARD |
author_sort |
McCARTHY, MICHAEL |
title |
Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal |
title_short |
Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal |
title_full |
Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal |
title_fullStr |
Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal |
title_full_unstemmed |
Ground-penetrating radar measurements of debris thickness on Lirung Glacier, Nepal |
title_sort |
ground-penetrating radar measurements of debris thickness on lirung glacier, nepal |
publisher |
Cambridge University Press (CUP) |
publishDate |
2017 |
url |
http://dx.doi.org/10.1017/jog.2017.18 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143017000181 |
genre |
Journal of Glaciology |
genre_facet |
Journal of Glaciology |
op_source |
Journal of Glaciology volume 63, issue 239, page 543-555 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2017.18 |
container_title |
Journal of Glaciology |
container_volume |
63 |
container_issue |
239 |
container_start_page |
543 |
op_container_end_page |
555 |
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1802646334449123328 |