Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams
Ice streams are corridors of fast-flowing ice that control mass transfers from continental ice sheets to oceans. Their flow speeds are known to accelerate and decelerate, their activity can switch on and off, and even their locations can shift entirely. Our analogue physical experiments reveal that...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus Publications
2018
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-12-2759-2018 https://doaj.org/article/80cce5937f1347daaeef3c111235782a |
id |
ftdoajarticles:oai:doaj.org/article:80cce5937f1347daaeef3c111235782a |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:80cce5937f1347daaeef3c111235782a 2023-05-15T18:32:26+02:00 Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams T. Lelandais É. Ravier S. Pochat O. Bourgeois C. Clark R. Mourgues P. Strzerzynski 2018-08-01T00:00:00Z https://doi.org/10.5194/tc-12-2759-2018 https://doaj.org/article/80cce5937f1347daaeef3c111235782a EN eng Copernicus Publications https://www.the-cryosphere.net/12/2759/2018/tc-12-2759-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-2759-2018 1994-0416 1994-0424 https://doaj.org/article/80cce5937f1347daaeef3c111235782a The Cryosphere, Vol 12, Pp 2759-2772 (2018) Environmental sciences GE1-350 Geology QE1-996.5 article 2018 ftdoajarticles https://doi.org/10.5194/tc-12-2759-2018 2022-12-31T10:18:50Z Ice streams are corridors of fast-flowing ice that control mass transfers from continental ice sheets to oceans. Their flow speeds are known to accelerate and decelerate, their activity can switch on and off, and even their locations can shift entirely. Our analogue physical experiments reveal that a life cycle incorporating evolving subglacial meltwater routing and bed erosion can govern this complex transitory behaviour. The modelled ice streams switch on and accelerate when subglacial water pockets drain as marginal outburst floods (basal decoupling). Then they decelerate when the lubricating water drainage system spontaneously organizes itself into channels that create tunnel valleys (partial basal recoupling). The ice streams surge or jump in location when these water drainage systems maintain low discharge but they ultimately switch off when tunnel valleys have expanded to develop efficient drainage systems. Beyond reconciling previously disconnected observations of modern and ancient ice streams into a single life cycle, the modelling suggests that tunnel valley development may be crucial in stabilizing portions of ice sheets during periods of climate change. Article in Journal/Newspaper The Cryosphere Directory of Open Access Journals: DOAJ Articles The Cryosphere 12 8 2759 2772 |
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 T. Lelandais É. Ravier S. Pochat O. Bourgeois C. Clark R. Mourgues P. Strzerzynski Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Ice streams are corridors of fast-flowing ice that control mass transfers from continental ice sheets to oceans. Their flow speeds are known to accelerate and decelerate, their activity can switch on and off, and even their locations can shift entirely. Our analogue physical experiments reveal that a life cycle incorporating evolving subglacial meltwater routing and bed erosion can govern this complex transitory behaviour. The modelled ice streams switch on and accelerate when subglacial water pockets drain as marginal outburst floods (basal decoupling). Then they decelerate when the lubricating water drainage system spontaneously organizes itself into channels that create tunnel valleys (partial basal recoupling). The ice streams surge or jump in location when these water drainage systems maintain low discharge but they ultimately switch off when tunnel valleys have expanded to develop efficient drainage systems. Beyond reconciling previously disconnected observations of modern and ancient ice streams into a single life cycle, the modelling suggests that tunnel valley development may be crucial in stabilizing portions of ice sheets during periods of climate change. |
format |
Article in Journal/Newspaper |
author |
T. Lelandais É. Ravier S. Pochat O. Bourgeois C. Clark R. Mourgues P. Strzerzynski |
author_facet |
T. Lelandais É. Ravier S. Pochat O. Bourgeois C. Clark R. Mourgues P. Strzerzynski |
author_sort |
T. Lelandais |
title |
Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams |
title_short |
Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams |
title_full |
Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams |
title_fullStr |
Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams |
title_full_unstemmed |
Modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams |
title_sort |
modelled subglacial floods and tunnel valleys control the life cycle of transitory ice streams |
publisher |
Copernicus Publications |
publishDate |
2018 |
url |
https://doi.org/10.5194/tc-12-2759-2018 https://doaj.org/article/80cce5937f1347daaeef3c111235782a |
genre |
The Cryosphere |
genre_facet |
The Cryosphere |
op_source |
The Cryosphere, Vol 12, Pp 2759-2772 (2018) |
op_relation |
https://www.the-cryosphere.net/12/2759/2018/tc-12-2759-2018.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-12-2759-2018 1994-0416 1994-0424 https://doaj.org/article/80cce5937f1347daaeef3c111235782a |
op_doi |
https://doi.org/10.5194/tc-12-2759-2018 |
container_title |
The Cryosphere |
container_volume |
12 |
container_issue |
8 |
container_start_page |
2759 |
op_container_end_page |
2772 |
_version_ |
1766216553441787904 |