Modelling the subglacial hydrology of the former Barents Sea Ice Sheet
Ice dynamics are strongly controlled by processes taking place at the interface between the ice and the underlying bed. In modern day ice sheets, up to 90% of mass is lost through fast-flowing corridors of ice, called ice streams. These are typically underlain by a thin layer of water and wet sedime...
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UiT Norges arktiske universitet
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ftunivtroemsoe:oai:munin.uit.no:10037/25064 2023-05-15T13:45:59+02:00 Modelling the subglacial hydrology of the former Barents Sea Ice Sheet Gudlaugsson, Eythor 2015-12-01 https://hdl.handle.net/10037/25064 eng eng UiT Norges arktiske universitet UiT The Arctic University of Norway Paper 1: Gudlaugsson, E., Humbert, A., Winsborrow, M. & Andreassen, K. (2013). Subglacial roughness of the former Barents Sea ice sheet. Journal of Geophysical Research - Earth Surface, 118 (4), 2546-2556. Also available in Munin at https://hdl.handle.net/10037/7361 . Paper 2: Gudlaugsson, E., Humbert, A., Kleiner, T., Kohler, J. & Andreassen, K. (2015). The influence of a model subglacial lake on ice dynamics and internal layering. (Manuscript). Now published in The Cryosphere, 10 (2), 751–760, 2016, available in Munin at https://hdl.handle.net/10037/10802 . Paper 3: Gudlaugsson, E., Humbert, A., Andreassen, K., Clason, C., Kleiner, T. & Beyer, S. Eurasian ice sheet dynamics and sensitivity to subglacial hydrology. (Manuscript). Now published in Journal of Glaciology, 63 (239), 556-564, 2017, available in Munin at https://hdl.handle.net/10037/12362 . 978-82-8236-196-5 (trykt) og 978-82-8236-197-2 (pdf) https://hdl.handle.net/10037/25064 openAccess Copyright 2015 The Author(s) VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 DOKTOR-004 Doctoral thesis Doktorgradsavhandling 2015 ftunivtroemsoe 2022-05-11T22:58:43Z Ice dynamics are strongly controlled by processes taking place at the interface between the ice and the underlying bed. In modern day ice sheets, up to 90% of mass is lost through fast-flowing corridors of ice, called ice streams. These are typically underlain by a thin layer of water and wet sediment, both of which promote fast flow. In recent years it has emerged that subglacial hydrology played an important role in the relatively fast disintegration of the Fennoscandian and the Barents Sea Ice Sheets (BSIS). The BSIS is a close historical analogue to the West Antarctic Ice sheet (WAIS) and understanding its demise could give important insight into the future evolution of the WAIS. In this study, we investigate the effect of subglacial water on the evolution of the Fennoscandian and the Barents Sea Ice Sheets. We do this by implementing a thin film model of water flow into an existing numerical ice sheet model and simulate the ice sheets growth and decay during the last glacial cycle. Additionally, we examine the influence of a subglacial lake on ice dynamics and isochrone layers within the ice. Basal water separates the ice and bed, softens the underlying sediments and greatly increases ice velocity. Including subglacial hydrology in numerical ice sheet models leads to less ice building up with time during glacial periods. Temperate areas of ice sheets are typically overestimated without it and deglaciation occurs more slowly. Subglacial water can form lakes underneath the ice that greatly affect its speed and thermal regime. Lake drainage can result in travelling waves at depth within isochrone layers, indicating the possibility of detecting past drainage events with ice penetrating radar. The effects of subglacial hydrology are important and accounting for them will be necessary in order to accurately estimate polar contributions to sea level change in the future. Doctoral or Postdoctoral Thesis Antarc* Antarctic Barents Sea Fennoscandian Ice Sheet Journal of Glaciology Sea ice The Cryosphere University of Tromsø: Munin Open Research Archive Antarctic Barents Sea West Antarctic Ice Sheet |
institution |
Open Polar |
collection |
University of Tromsø: Munin Open Research Archive |
op_collection_id |
ftunivtroemsoe |
language |
English |
topic |
VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 DOKTOR-004 |
spellingShingle |
VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 DOKTOR-004 Gudlaugsson, Eythor Modelling the subglacial hydrology of the former Barents Sea Ice Sheet |
topic_facet |
VDP::Mathematics and natural science: 400::Geosciences: 450::Quaternary geology glaciology: 465 VDP::Matematikk og Naturvitenskap: 400::Geofag: 450::Kvartærgeologi glasiologi: 465 DOKTOR-004 |
description |
Ice dynamics are strongly controlled by processes taking place at the interface between the ice and the underlying bed. In modern day ice sheets, up to 90% of mass is lost through fast-flowing corridors of ice, called ice streams. These are typically underlain by a thin layer of water and wet sediment, both of which promote fast flow. In recent years it has emerged that subglacial hydrology played an important role in the relatively fast disintegration of the Fennoscandian and the Barents Sea Ice Sheets (BSIS). The BSIS is a close historical analogue to the West Antarctic Ice sheet (WAIS) and understanding its demise could give important insight into the future evolution of the WAIS. In this study, we investigate the effect of subglacial water on the evolution of the Fennoscandian and the Barents Sea Ice Sheets. We do this by implementing a thin film model of water flow into an existing numerical ice sheet model and simulate the ice sheets growth and decay during the last glacial cycle. Additionally, we examine the influence of a subglacial lake on ice dynamics and isochrone layers within the ice. Basal water separates the ice and bed, softens the underlying sediments and greatly increases ice velocity. Including subglacial hydrology in numerical ice sheet models leads to less ice building up with time during glacial periods. Temperate areas of ice sheets are typically overestimated without it and deglaciation occurs more slowly. Subglacial water can form lakes underneath the ice that greatly affect its speed and thermal regime. Lake drainage can result in travelling waves at depth within isochrone layers, indicating the possibility of detecting past drainage events with ice penetrating radar. The effects of subglacial hydrology are important and accounting for them will be necessary in order to accurately estimate polar contributions to sea level change in the future. |
format |
Doctoral or Postdoctoral Thesis |
author |
Gudlaugsson, Eythor |
author_facet |
Gudlaugsson, Eythor |
author_sort |
Gudlaugsson, Eythor |
title |
Modelling the subglacial hydrology of the former Barents Sea Ice Sheet |
title_short |
Modelling the subglacial hydrology of the former Barents Sea Ice Sheet |
title_full |
Modelling the subglacial hydrology of the former Barents Sea Ice Sheet |
title_fullStr |
Modelling the subglacial hydrology of the former Barents Sea Ice Sheet |
title_full_unstemmed |
Modelling the subglacial hydrology of the former Barents Sea Ice Sheet |
title_sort |
modelling the subglacial hydrology of the former barents sea ice sheet |
publisher |
UiT Norges arktiske universitet |
publishDate |
2015 |
url |
https://hdl.handle.net/10037/25064 |
geographic |
Antarctic Barents Sea West Antarctic Ice Sheet |
geographic_facet |
Antarctic Barents Sea West Antarctic Ice Sheet |
genre |
Antarc* Antarctic Barents Sea Fennoscandian Ice Sheet Journal of Glaciology Sea ice The Cryosphere |
genre_facet |
Antarc* Antarctic Barents Sea Fennoscandian Ice Sheet Journal of Glaciology Sea ice The Cryosphere |
op_relation |
Paper 1: Gudlaugsson, E., Humbert, A., Winsborrow, M. & Andreassen, K. (2013). Subglacial roughness of the former Barents Sea ice sheet. Journal of Geophysical Research - Earth Surface, 118 (4), 2546-2556. Also available in Munin at https://hdl.handle.net/10037/7361 . Paper 2: Gudlaugsson, E., Humbert, A., Kleiner, T., Kohler, J. & Andreassen, K. (2015). The influence of a model subglacial lake on ice dynamics and internal layering. (Manuscript). Now published in The Cryosphere, 10 (2), 751–760, 2016, available in Munin at https://hdl.handle.net/10037/10802 . Paper 3: Gudlaugsson, E., Humbert, A., Andreassen, K., Clason, C., Kleiner, T. & Beyer, S. Eurasian ice sheet dynamics and sensitivity to subglacial hydrology. (Manuscript). Now published in Journal of Glaciology, 63 (239), 556-564, 2017, available in Munin at https://hdl.handle.net/10037/12362 . 978-82-8236-196-5 (trykt) og 978-82-8236-197-2 (pdf) https://hdl.handle.net/10037/25064 |
op_rights |
openAccess Copyright 2015 The Author(s) |
_version_ |
1766234664843870208 |