Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry
Melt from supraglacial ice cliffs is an important contributor to the mass loss of debris-covered glaciers. However, ice cliff contribution is difficult to quantify as they are highly dynamic features, and the paucity of observations of melt rates and their variability leads to large modelling uncert...
Published in: | The Cryosphere |
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Online Access: | https://nrl.northumbria.ac.uk/id/eprint/50627/ https://doi.org/10.5194/tc-16-4701-2022 https://nrl.northumbria.ac.uk/id/eprint/50627/1/tc-16-4701-2022.pdf |
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ftunivnorthumb:oai:nrl.northumbria.ac.uk:50627 2023-05-15T18:32:34+02:00 Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry Kneib, Marin Miles, Evan S. Buri, Pascal Fugger, Stefan McCarthy, Michael Shaw, Thomas Chuanxi, Zhao Truffer, Martin Westoby, Matt Yang, Wei Pellicciotti, Francesca 2022-11-11 text https://nrl.northumbria.ac.uk/id/eprint/50627/ https://doi.org/10.5194/tc-16-4701-2022 https://nrl.northumbria.ac.uk/id/eprint/50627/1/tc-16-4701-2022.pdf en eng Coperincus https://nrl.northumbria.ac.uk/id/eprint/50627/1/tc-16-4701-2022.pdf Kneib, Marin, Miles, Evan S., Buri, Pascal, Fugger, Stefan, McCarthy, Michael, Shaw, Thomas, Chuanxi, Zhao, Truffer, Martin, Westoby, Matt, Yang, Wei and Pellicciotti, Francesca (2022) Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry. The Cryosphere, 16 (11). pp. 4701-4725. ISSN 1994-0424 cc_by_4_0 CC-BY F800 Physical and Terrestrial Geographical and Environmental Sciences Article PeerReviewed 2022 ftunivnorthumb https://doi.org/10.5194/tc-16-4701-2022 2022-11-17T23:30:49Z Melt from supraglacial ice cliffs is an important contributor to the mass loss of debris-covered glaciers. However, ice cliff contribution is difficult to quantify as they are highly dynamic features, and the paucity of observations of melt rates and their variability leads to large modelling uncertainties. We quantify monsoon season melt and 3D evolution of four ice cliffs over two debris-covered glaciers in High Mountain Asia (Langtang Glacier, Nepal, and 24K Glacier, China) at very high resolution using terrestrial photogrammetry applied to imagery captured from time-lapse cameras installed on lateral moraines. We derive weekly flow-corrected digital elevation models (DEMs) of the glacier surface with a maximum vertical bias of ±0.2 m for Langtang Glacier and ±0.05 m for 24K Glacier and use change detection to determine distributed melt rates at the surfaces of the ice cliffs throughout the study period. We compare the measured melt patterns with those derived from a 3D energy balance model to derive the contribution of the main energy fluxes. We find that ice cliff melt varies considerably throughout the melt season, with maximum melt rates of 5 to 8 cm d−1, and their average melt rates are 11–14 (Langtang) and 4.5 (24K) times higher than the surrounding debris-covered ice. Our results highlight the influence of redistributed supraglacial debris on cliff melt. At both sites, ice cliff albedo is influenced by the presence of thin debris at the ice cliff surface, which is largely controlled on 24K Glacier by liquid precipitation events that wash away this debris. Slightly thicker or patchy debris reduces melt by 1–3 cm d−1 at all sites. Ultimately, our observations show a strong spatio-temporal variability in cliff area at each site, which is controlled by supraglacial streams and ponds and englacial cavities that promote debris slope destabilisation and the lateral expansion of the cliffs. These findings highlight the need to better represent processes of debris redistribution in ice cliff models, to in turn ... Article in Journal/Newspaper The Cryosphere Northumbria University, Newcastle: Northumbria Research Link (NRL) The Cryosphere 16 11 4701 4725 |
institution |
Open Polar |
collection |
Northumbria University, Newcastle: Northumbria Research Link (NRL) |
op_collection_id |
ftunivnorthumb |
language |
English |
topic |
F800 Physical and Terrestrial Geographical and Environmental Sciences |
spellingShingle |
F800 Physical and Terrestrial Geographical and Environmental Sciences Kneib, Marin Miles, Evan S. Buri, Pascal Fugger, Stefan McCarthy, Michael Shaw, Thomas Chuanxi, Zhao Truffer, Martin Westoby, Matt Yang, Wei Pellicciotti, Francesca Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry |
topic_facet |
F800 Physical and Terrestrial Geographical and Environmental Sciences |
description |
Melt from supraglacial ice cliffs is an important contributor to the mass loss of debris-covered glaciers. However, ice cliff contribution is difficult to quantify as they are highly dynamic features, and the paucity of observations of melt rates and their variability leads to large modelling uncertainties. We quantify monsoon season melt and 3D evolution of four ice cliffs over two debris-covered glaciers in High Mountain Asia (Langtang Glacier, Nepal, and 24K Glacier, China) at very high resolution using terrestrial photogrammetry applied to imagery captured from time-lapse cameras installed on lateral moraines. We derive weekly flow-corrected digital elevation models (DEMs) of the glacier surface with a maximum vertical bias of ±0.2 m for Langtang Glacier and ±0.05 m for 24K Glacier and use change detection to determine distributed melt rates at the surfaces of the ice cliffs throughout the study period. We compare the measured melt patterns with those derived from a 3D energy balance model to derive the contribution of the main energy fluxes. We find that ice cliff melt varies considerably throughout the melt season, with maximum melt rates of 5 to 8 cm d−1, and their average melt rates are 11–14 (Langtang) and 4.5 (24K) times higher than the surrounding debris-covered ice. Our results highlight the influence of redistributed supraglacial debris on cliff melt. At both sites, ice cliff albedo is influenced by the presence of thin debris at the ice cliff surface, which is largely controlled on 24K Glacier by liquid precipitation events that wash away this debris. Slightly thicker or patchy debris reduces melt by 1–3 cm d−1 at all sites. Ultimately, our observations show a strong spatio-temporal variability in cliff area at each site, which is controlled by supraglacial streams and ponds and englacial cavities that promote debris slope destabilisation and the lateral expansion of the cliffs. These findings highlight the need to better represent processes of debris redistribution in ice cliff models, to in turn ... |
format |
Article in Journal/Newspaper |
author |
Kneib, Marin Miles, Evan S. Buri, Pascal Fugger, Stefan McCarthy, Michael Shaw, Thomas Chuanxi, Zhao Truffer, Martin Westoby, Matt Yang, Wei Pellicciotti, Francesca |
author_facet |
Kneib, Marin Miles, Evan S. Buri, Pascal Fugger, Stefan McCarthy, Michael Shaw, Thomas Chuanxi, Zhao Truffer, Martin Westoby, Matt Yang, Wei Pellicciotti, Francesca |
author_sort |
Kneib, Marin |
title |
Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry |
title_short |
Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry |
title_full |
Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry |
title_fullStr |
Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry |
title_full_unstemmed |
Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry |
title_sort |
sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry |
publisher |
Coperincus |
publishDate |
2022 |
url |
https://nrl.northumbria.ac.uk/id/eprint/50627/ https://doi.org/10.5194/tc-16-4701-2022 https://nrl.northumbria.ac.uk/id/eprint/50627/1/tc-16-4701-2022.pdf |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_relation |
https://nrl.northumbria.ac.uk/id/eprint/50627/1/tc-16-4701-2022.pdf Kneib, Marin, Miles, Evan S., Buri, Pascal, Fugger, Stefan, McCarthy, Michael, Shaw, Thomas, Chuanxi, Zhao, Truffer, Martin, Westoby, Matt, Yang, Wei and Pellicciotti, Francesca (2022) Sub-seasonal variability of supraglacial ice cliff melt rates and associated processes from time-lapse photogrammetry. The Cryosphere, 16 (11). pp. 4701-4725. ISSN 1994-0424 |
op_rights |
cc_by_4_0 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.5194/tc-16-4701-2022 |
container_title |
The Cryosphere |
container_volume |
16 |
container_issue |
11 |
container_start_page |
4701 |
op_container_end_page |
4725 |
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1766216780787744768 |