Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses 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...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/583262 2023-05-15T18:32:13+02:00 Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry Kneib, Marin Miles, Evan S. Buri, Pascal Fugger, Stefan McCarthy, Michael Shaw, Thomas E. Zhao, Chuanxi Truffer, Martin Westoby, Matthew J. Yang, Wei Pellicciotti, Francesca 2022 application/application/pdf https://hdl.handle.net/20.500.11850/583262 https://doi.org/10.3929/ethz-b-000583262 en eng Copernicus info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-16-4701-2022 info:eu-repo/semantics/altIdentifier/wos/000886624200001 http://hdl.handle.net/20.500.11850/583262 doi:10.3929/ethz-b-000583262 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International CC-BY The Cryosphere, 16 (11) info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2022 ftethz https://doi.org/20.500.11850/583262 https://doi.org/10.3929/ethz-b-000583262 https://doi.org/10.5194/tc-16-4701-2022 2023-02-13T01:15:22Z 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 ETH Zürich Research Collection |
institution |
Open Polar |
collection |
ETH Zürich Research Collection |
op_collection_id |
ftethz |
language |
English |
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 E. Zhao, Chuanxi Truffer, Martin Westoby, Matthew J. Yang, Wei Pellicciotti, Francesca |
spellingShingle |
Kneib, Marin Miles, Evan S. Buri, Pascal Fugger, Stefan McCarthy, Michael Shaw, Thomas E. Zhao, Chuanxi Truffer, Martin Westoby, Matthew J. Yang, Wei Pellicciotti, Francesca Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry |
author_facet |
Kneib, Marin Miles, Evan S. Buri, Pascal Fugger, Stefan McCarthy, Michael Shaw, Thomas E. Zhao, Chuanxi Truffer, Martin Westoby, Matthew J. Yang, Wei Pellicciotti, Francesca |
author_sort |
Kneib, Marin |
title |
Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry |
title_short |
Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry |
title_full |
Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry |
title_fullStr |
Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry |
title_full_unstemmed |
Sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry |
title_sort |
sub-seasonal variability of supraglacial ice cliff melt rates and associatedprocesses from time-lapse photogrammetry |
publisher |
Copernicus |
publishDate |
2022 |
url |
https://hdl.handle.net/20.500.11850/583262 https://doi.org/10.3929/ethz-b-000583262 |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
The Cryosphere, 16 (11) |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/tc-16-4701-2022 info:eu-repo/semantics/altIdentifier/wos/000886624200001 http://hdl.handle.net/20.500.11850/583262 doi:10.3929/ethz-b-000583262 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/20.500.11850/583262 https://doi.org/10.3929/ethz-b-000583262 https://doi.org/10.5194/tc-16-4701-2022 |
_version_ |
1766216307805519872 |