Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier
Abstract Frontal ablation from tidewater glaciers is a major component of the total mass loss from the Greenland ice sheet. It remains unclear, however, how changes in atmospheric and oceanic temperatures translate into changes in frontal ablation, in part due to sparse observations at sufficiently...
Published in: | Journal of Glaciology |
---|---|
Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
2020
|
Subjects: | |
Online Access: | http://dx.doi.org/10.1017/jog.2020.109 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020001094 |
id |
crcambridgeupr:10.1017/jog.2020.109 |
---|---|
record_format |
openpolar |
spelling |
crcambridgeupr:10.1017/jog.2020.109 2024-05-19T07:40:42+00:00 Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier Bunce, Charlie Nienow, Peter Sole, Andrew Cowton, Tom Davison, Benjamin 2020 http://dx.doi.org/10.1017/jog.2020.109 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020001094 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by/4.0/ Journal of Glaciology volume 67, issue 262, page 343-352 ISSN 0022-1430 1727-5652 journal-article 2020 crcambridgeupr https://doi.org/10.1017/jog.2020.109 2024-05-02T06:51:17Z Abstract Frontal ablation from tidewater glaciers is a major component of the total mass loss from the Greenland ice sheet. It remains unclear, however, how changes in atmospheric and oceanic temperatures translate into changes in frontal ablation, in part due to sparse observations at sufficiently high spatial and temporal resolution. We present high-frequency time-lapse imagery (photos every 30 min) of iceberg calving and meltwater plumes at Kangiata Nunaata Sermia (KNS), southwest Greenland, during June–October 2017, alongside satellite-derived ice velocities and modelled subglacial discharge. Early in the melt season, we infer a subglacial hydrological network with multiple outlets that would theoretically distribute discharge and enhance undercutting by submarine melt, an inference supported by our observations of terminus-wide calving during this period. During the melt season, we infer hydraulic evolution to a relatively more channelised subglacial drainage configuration, based on meltwater plume visibility indicating focused emergence of subglacial water; these observations coincide with a reduction in terminus-wide calving and transition to an incised planform terminus geometry. We suggest that temporal variations in subglacial discharge and near-terminus subglacial hydraulic efficiency exert considerable influence on calving and frontal ablation at KNS. Article in Journal/Newspaper glacier Greenland greenlandic Ice Sheet Journal of Glaciology Tidewater Cambridge University Press Journal of Glaciology 67 262 343 352 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Abstract Frontal ablation from tidewater glaciers is a major component of the total mass loss from the Greenland ice sheet. It remains unclear, however, how changes in atmospheric and oceanic temperatures translate into changes in frontal ablation, in part due to sparse observations at sufficiently high spatial and temporal resolution. We present high-frequency time-lapse imagery (photos every 30 min) of iceberg calving and meltwater plumes at Kangiata Nunaata Sermia (KNS), southwest Greenland, during June–October 2017, alongside satellite-derived ice velocities and modelled subglacial discharge. Early in the melt season, we infer a subglacial hydrological network with multiple outlets that would theoretically distribute discharge and enhance undercutting by submarine melt, an inference supported by our observations of terminus-wide calving during this period. During the melt season, we infer hydraulic evolution to a relatively more channelised subglacial drainage configuration, based on meltwater plume visibility indicating focused emergence of subglacial water; these observations coincide with a reduction in terminus-wide calving and transition to an incised planform terminus geometry. We suggest that temporal variations in subglacial discharge and near-terminus subglacial hydraulic efficiency exert considerable influence on calving and frontal ablation at KNS. |
format |
Article in Journal/Newspaper |
author |
Bunce, Charlie Nienow, Peter Sole, Andrew Cowton, Tom Davison, Benjamin |
spellingShingle |
Bunce, Charlie Nienow, Peter Sole, Andrew Cowton, Tom Davison, Benjamin Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier |
author_facet |
Bunce, Charlie Nienow, Peter Sole, Andrew Cowton, Tom Davison, Benjamin |
author_sort |
Bunce, Charlie |
title |
Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier |
title_short |
Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier |
title_full |
Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier |
title_fullStr |
Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier |
title_full_unstemmed |
Influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large Greenlandic tidewater glacier |
title_sort |
influence of glacier runoff and near-terminus subglacial hydrology on frontal ablation at a large greenlandic tidewater glacier |
publisher |
Cambridge University Press (CUP) |
publishDate |
2020 |
url |
http://dx.doi.org/10.1017/jog.2020.109 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143020001094 |
genre |
glacier Greenland greenlandic Ice Sheet Journal of Glaciology Tidewater |
genre_facet |
glacier Greenland greenlandic Ice Sheet Journal of Glaciology Tidewater |
op_source |
Journal of Glaciology volume 67, issue 262, page 343-352 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2020.109 |
container_title |
Journal of Glaciology |
container_volume |
67 |
container_issue |
262 |
container_start_page |
343 |
op_container_end_page |
352 |
_version_ |
1799480287149686784 |