Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels
Subglacial meltwater channels (N-channels) are attributed to erosion by meltwater in subglacial conduits. They exert a major control on meltwater accumulation at the base of ice sheets, serving as drainage pathways and modifying ice flow rates. The study of exposed relict subglacial channels offers...
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Copernicus Publications
2018
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Online Access: | https://doi.org/10.5194/tc-12-1461-2018 https://doaj.org/article/e0b58c886a634601b1f901b9661054bf |
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ftdoajarticles:oai:doaj.org/article:e0b58c886a634601b1f901b9661054bf 2023-05-15T14:28:56+02:00 Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels A. Grau Galofre A. M. Jellinek G. R. Osinski M. Zanetti A. Kukko 2018-04-01T00:00:00Z https://doi.org/10.5194/tc-12-1461-2018 https://doaj.org/article/e0b58c886a634601b1f901b9661054bf EN eng Copernicus Publications https://www.the-cryosphere.net/12/1461/2018/tc-12-1461-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-1461-2018 1994-0416 1994-0424 https://doaj.org/article/e0b58c886a634601b1f901b9661054bf The Cryosphere, Vol 12, Pp 1461-1478 (2018) Environmental sciences GE1-350 Geology QE1-996.5 article 2018 ftdoajarticles https://doi.org/10.5194/tc-12-1461-2018 2022-12-31T16:25:40Z Subglacial meltwater channels (N-channels) are attributed to erosion by meltwater in subglacial conduits. They exert a major control on meltwater accumulation at the base of ice sheets, serving as drainage pathways and modifying ice flow rates. The study of exposed relict subglacial channels offers a unique opportunity to characterize the geomorphologic fingerprint of subglacial erosion as well as study the structure and characteristics of ice sheet drainage systems. In this study we present detailed field and remote sensing observations of exposed subglacial meltwater channels in excellent preservation state on Devon Island (Canadian Arctic Archipelago). We characterize channel cross section, longitudinal profiles, and network morphologies and establish the spatial extent and distinctive characteristics of subglacial drainage systems. We use field-based GPS measurements of subglacial channel longitudinal profiles, along with stereo imagery-derived digital surface models (DSMs), and novel kinematic portable lidar data to establish a detailed characterization of subglacial channels in our field study area, including their distinction from rivers and other meltwater drainage systems. Subglacial channels typically cluster in groups of ∼ 10 channels and are oriented perpendicular to active or former ice margins. Although their overall direction generally follows topographic gradients, channels can be oblique to topographic gradients and have undulating longitudinal profiles. We also observe that the width of first-order tributaries is 1 to 2 orders of magnitude larger than in Devon Island river systems and approximately constant. Furthermore, our findings are consistent with theoretical expectations drawn from analyses of flow driven by gradients in effective water pressure related to variations in ice thickness. Our field and remote sensing observations represent the first high-resolution study of the subglacial geomorphology of the high Arctic, and provide quantitative and qualitative descriptions of subglacial ... Article in Journal/Newspaper Arctic Archipelago Arctic Canadian Arctic Archipelago Devon Island Ice Sheet The Cryosphere Directory of Open Access Journals: DOAJ Articles Arctic Canada Canadian Arctic Archipelago Devon Island ENVELOPE(-88.000,-88.000,75.252,75.252) The Cryosphere 12 4 1461 1478 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 A. Grau Galofre A. M. Jellinek G. R. Osinski M. Zanetti A. Kukko Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Subglacial meltwater channels (N-channels) are attributed to erosion by meltwater in subglacial conduits. They exert a major control on meltwater accumulation at the base of ice sheets, serving as drainage pathways and modifying ice flow rates. The study of exposed relict subglacial channels offers a unique opportunity to characterize the geomorphologic fingerprint of subglacial erosion as well as study the structure and characteristics of ice sheet drainage systems. In this study we present detailed field and remote sensing observations of exposed subglacial meltwater channels in excellent preservation state on Devon Island (Canadian Arctic Archipelago). We characterize channel cross section, longitudinal profiles, and network morphologies and establish the spatial extent and distinctive characteristics of subglacial drainage systems. We use field-based GPS measurements of subglacial channel longitudinal profiles, along with stereo imagery-derived digital surface models (DSMs), and novel kinematic portable lidar data to establish a detailed characterization of subglacial channels in our field study area, including their distinction from rivers and other meltwater drainage systems. Subglacial channels typically cluster in groups of ∼ 10 channels and are oriented perpendicular to active or former ice margins. Although their overall direction generally follows topographic gradients, channels can be oblique to topographic gradients and have undulating longitudinal profiles. We also observe that the width of first-order tributaries is 1 to 2 orders of magnitude larger than in Devon Island river systems and approximately constant. Furthermore, our findings are consistent with theoretical expectations drawn from analyses of flow driven by gradients in effective water pressure related to variations in ice thickness. Our field and remote sensing observations represent the first high-resolution study of the subglacial geomorphology of the high Arctic, and provide quantitative and qualitative descriptions of subglacial ... |
format |
Article in Journal/Newspaper |
author |
A. Grau Galofre A. M. Jellinek G. R. Osinski M. Zanetti A. Kukko |
author_facet |
A. Grau Galofre A. M. Jellinek G. R. Osinski M. Zanetti A. Kukko |
author_sort |
A. Grau Galofre |
title |
Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels |
title_short |
Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels |
title_full |
Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels |
title_fullStr |
Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels |
title_full_unstemmed |
Subglacial drainage patterns of Devon Island, Canada: detailed comparison of rivers and subglacial meltwater channels |
title_sort |
subglacial drainage patterns of devon island, canada: detailed comparison of rivers and subglacial meltwater channels |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-1461-2018 https://doaj.org/article/e0b58c886a634601b1f901b9661054bf |
long_lat |
ENVELOPE(-88.000,-88.000,75.252,75.252) |
geographic |
Arctic Canada Canadian Arctic Archipelago Devon Island |
geographic_facet |
Arctic Canada Canadian Arctic Archipelago Devon Island |
genre |
Arctic Archipelago Arctic Canadian Arctic Archipelago Devon Island Ice Sheet The Cryosphere |
genre_facet |
Arctic Archipelago Arctic Canadian Arctic Archipelago Devon Island Ice Sheet The Cryosphere |
op_source |
The Cryosphere, Vol 12, Pp 1461-1478 (2018) |
op_relation |
https://www.the-cryosphere.net/12/1461/2018/tc-12-1461-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-1461-2018 1994-0416 1994-0424 https://doaj.org/article/e0b58c886a634601b1f901b9661054bf |
op_doi |
https://doi.org/10.5194/tc-12-1461-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
4 |
container_start_page |
1461 |
op_container_end_page |
1478 |
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1766303060083081216 |