Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska
Frontal ablation is a major component of the mass budget of calving glaciers, strongly affecting their dynamics. Most global-scale ice volume estimates to date still suffer from considerable uncertainties related to (i) the implemented frontal ablation parameterization or (ii) not accounting for fro...
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ftdoajarticles:oai:doaj.org/article:abc194eba7ed441b85a696450999245b 2023-05-15T16:20:25+02:00 Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska B. Recinos F. Maussion T. Rothenpieler B. Marzeion 2019-10-01T00:00:00Z https://doi.org/10.5194/tc-13-2657-2019 https://doaj.org/article/abc194eba7ed441b85a696450999245b EN eng Copernicus Publications https://www.the-cryosphere.net/13/2657/2019/tc-13-2657-2019.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-13-2657-2019 1994-0416 1994-0424 https://doaj.org/article/abc194eba7ed441b85a696450999245b The Cryosphere, Vol 13, Pp 2657-2672 (2019) Environmental sciences GE1-350 Geology QE1-996.5 article 2019 ftdoajarticles https://doi.org/10.5194/tc-13-2657-2019 2022-12-31T03:11:51Z Frontal ablation is a major component of the mass budget of calving glaciers, strongly affecting their dynamics. Most global-scale ice volume estimates to date still suffer from considerable uncertainties related to (i) the implemented frontal ablation parameterization or (ii) not accounting for frontal ablation at all in the glacier model. To improve estimates of the ice thickness distribution of glaciers, it is thus important to identify and test low-cost and robust parameterizations of this process. By implementing such parameterization into the ice thickness estimation module of the Open Global Glacier Model (OGGM v1.1.2), we conduct a first assessment of the impact of accounting for frontal ablation on the estimate of ice stored in glaciers in Alaska. We find that inversion methods based on mass conservation systematically underestimate the mass turnover and, therefore, the thickness of tidewater glaciers when neglecting frontal ablation. This underestimation can amount to up to 19 % on a regional scale and up to 30 % for individual glaciers. The effect is independent of the size of the glacier. Additionally, we perform different sensitivity experiments to study the influence of (i) a constant of proportionality ( k ) used in the frontal ablation parameterization, (ii) Glen's temperature-dependent creep parameter ( A ) and (iii) a sliding velocity parameter ( f s ) on the regional dynamics of Alaska tidewater glaciers. OGGM is able to reproduce previous regional frontal ablation estimates, applying a number of combinations of values for k , Glen's A and f s . Our sensitivity studies also show that differences in thickness between accounting for and not accounting for frontal ablation occur mainly at the lower parts of the glacier, both above and below sea level. This indicates that not accounting for frontal ablation will have an impact on the estimate of the glaciers' potential contribution to sea-level rise. Introducing frontal ablation increases the volume estimate of Alaska marine-terminating glaciers ... Article in Journal/Newspaper glacier glaciers The Cryosphere Tidewater Alaska Directory of Open Access Journals: DOAJ Articles The Cryosphere 13 10 2657 2672 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 B. Recinos F. Maussion T. Rothenpieler B. Marzeion Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Frontal ablation is a major component of the mass budget of calving glaciers, strongly affecting their dynamics. Most global-scale ice volume estimates to date still suffer from considerable uncertainties related to (i) the implemented frontal ablation parameterization or (ii) not accounting for frontal ablation at all in the glacier model. To improve estimates of the ice thickness distribution of glaciers, it is thus important to identify and test low-cost and robust parameterizations of this process. By implementing such parameterization into the ice thickness estimation module of the Open Global Glacier Model (OGGM v1.1.2), we conduct a first assessment of the impact of accounting for frontal ablation on the estimate of ice stored in glaciers in Alaska. We find that inversion methods based on mass conservation systematically underestimate the mass turnover and, therefore, the thickness of tidewater glaciers when neglecting frontal ablation. This underestimation can amount to up to 19 % on a regional scale and up to 30 % for individual glaciers. The effect is independent of the size of the glacier. Additionally, we perform different sensitivity experiments to study the influence of (i) a constant of proportionality ( k ) used in the frontal ablation parameterization, (ii) Glen's temperature-dependent creep parameter ( A ) and (iii) a sliding velocity parameter ( f s ) on the regional dynamics of Alaska tidewater glaciers. OGGM is able to reproduce previous regional frontal ablation estimates, applying a number of combinations of values for k , Glen's A and f s . Our sensitivity studies also show that differences in thickness between accounting for and not accounting for frontal ablation occur mainly at the lower parts of the glacier, both above and below sea level. This indicates that not accounting for frontal ablation will have an impact on the estimate of the glaciers' potential contribution to sea-level rise. Introducing frontal ablation increases the volume estimate of Alaska marine-terminating glaciers ... |
format |
Article in Journal/Newspaper |
author |
B. Recinos F. Maussion T. Rothenpieler B. Marzeion |
author_facet |
B. Recinos F. Maussion T. Rothenpieler B. Marzeion |
author_sort |
B. Recinos |
title |
Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska |
title_short |
Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska |
title_full |
Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska |
title_fullStr |
Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska |
title_full_unstemmed |
Impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in Alaska |
title_sort |
impact of frontal ablation on the ice thickness estimation of marine-terminating glaciers in alaska |
publisher |
Copernicus Publications |
publishDate |
2019 |
url |
https://doi.org/10.5194/tc-13-2657-2019 https://doaj.org/article/abc194eba7ed441b85a696450999245b |
genre |
glacier glaciers The Cryosphere Tidewater Alaska |
genre_facet |
glacier glaciers The Cryosphere Tidewater Alaska |
op_source |
The Cryosphere, Vol 13, Pp 2657-2672 (2019) |
op_relation |
https://www.the-cryosphere.net/13/2657/2019/tc-13-2657-2019.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-13-2657-2019 1994-0416 1994-0424 https://doaj.org/article/abc194eba7ed441b85a696450999245b |
op_doi |
https://doi.org/10.5194/tc-13-2657-2019 |
container_title |
The Cryosphere |
container_volume |
13 |
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10 |
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2657 |
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2672 |
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