Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet
Marine-terminating glaciers and ice streams are important controls of ice sheet mass balance. However, understanding of their long-term response to external forcing is limited by relatively short observational records of present-day glaciers and sparse geologic evidence for paleo-glaciers. Here we u...
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Online Access: | https://hdl.handle.net/1956/18162 https://doi.org/10.1016/j.quascirev.2018.07.004 |
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ftunivbergen:oai:bora.uib.no:1956/18162 2023-05-15T16:39:33+02:00 Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet Åkesson, Henning Morlighem, Mathieu Nisancioglu, Kerim Hestnes Svendsen, John-Inge Mangerud, Jan 2018-09 application/pdf https://hdl.handle.net/1956/18162 https://doi.org/10.1016/j.quascirev.2018.07.004 eng eng Elsevier Deglaciation of the Norwegian fjords urn:issn:0277-3791 https://hdl.handle.net/1956/18162 https://doi.org/10.1016/j.quascirev.2018.07.004 cristin:1597933 Attribution CC BY-NC-ND http://creativecommons.org/licenses/by-nc-nd/4.0/ Copyright 2018 The Author(s) Quaternary Science Reviews 195 32-47 Ice sheet modelling Grounding line dynamics Marine-terminating glaciers Deglaciation Ice-ocean interactions Surface mass balance Younger dryas Norway Eurasian ice sheet Scandinavian ice sheet Peer reviewed Journal article 2018 ftunivbergen https://doi.org/10.1016/j.quascirev.2018.07.004 2023-03-14T17:40:10Z Marine-terminating glaciers and ice streams are important controls of ice sheet mass balance. However, understanding of their long-term response to external forcing is limited by relatively short observational records of present-day glaciers and sparse geologic evidence for paleo-glaciers. Here we use a high-resolution ice sheet model with an accurate representation of grounding line dynamics to study the deglaciation of the marine-based south-western Norwegian sector of the Scandinavian Ice Sheet and its sensitivity to ocean and atmosphere forcing. We find that the regional response to a uniform climate change is highly dependent on the local bedrock topography, consistent with ice sheet reconstructions. Our simulations suggest that ocean warming is able to trigger initial retreat in several fjords, but is not sufficient to explain retreat everywhere. Widespread retreat requires additional ice thinning driven by surface melt. Once retreat is triggered, the underlying bedrock topography and fjord width control the rate and extent of retreat, while multi-millennial changes over the course of deglaciation are modulated by surface melt. We suggest that fjord geometry, ice-ocean interactions and grounding line dynamics are vital controls of decadal-to centennial scale ice sheet mass loss. However, we postulate that atmospheric changes are the most important drivers of widespread ice sheet demise, and will likely trump oceanic influence on future ice sheet mass loss and resulting sea level rise over centennial and longer time scales. publishedVersion Article in Journal/Newspaper Ice Sheet University of Bergen: Bergen Open Research Archive (BORA-UiB) Norway Quaternary Science Reviews 195 32 47 |
institution |
Open Polar |
collection |
University of Bergen: Bergen Open Research Archive (BORA-UiB) |
op_collection_id |
ftunivbergen |
language |
English |
topic |
Ice sheet modelling Grounding line dynamics Marine-terminating glaciers Deglaciation Ice-ocean interactions Surface mass balance Younger dryas Norway Eurasian ice sheet Scandinavian ice sheet |
spellingShingle |
Ice sheet modelling Grounding line dynamics Marine-terminating glaciers Deglaciation Ice-ocean interactions Surface mass balance Younger dryas Norway Eurasian ice sheet Scandinavian ice sheet Åkesson, Henning Morlighem, Mathieu Nisancioglu, Kerim Hestnes Svendsen, John-Inge Mangerud, Jan Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet |
topic_facet |
Ice sheet modelling Grounding line dynamics Marine-terminating glaciers Deglaciation Ice-ocean interactions Surface mass balance Younger dryas Norway Eurasian ice sheet Scandinavian ice sheet |
description |
Marine-terminating glaciers and ice streams are important controls of ice sheet mass balance. However, understanding of their long-term response to external forcing is limited by relatively short observational records of present-day glaciers and sparse geologic evidence for paleo-glaciers. Here we use a high-resolution ice sheet model with an accurate representation of grounding line dynamics to study the deglaciation of the marine-based south-western Norwegian sector of the Scandinavian Ice Sheet and its sensitivity to ocean and atmosphere forcing. We find that the regional response to a uniform climate change is highly dependent on the local bedrock topography, consistent with ice sheet reconstructions. Our simulations suggest that ocean warming is able to trigger initial retreat in several fjords, but is not sufficient to explain retreat everywhere. Widespread retreat requires additional ice thinning driven by surface melt. Once retreat is triggered, the underlying bedrock topography and fjord width control the rate and extent of retreat, while multi-millennial changes over the course of deglaciation are modulated by surface melt. We suggest that fjord geometry, ice-ocean interactions and grounding line dynamics are vital controls of decadal-to centennial scale ice sheet mass loss. However, we postulate that atmospheric changes are the most important drivers of widespread ice sheet demise, and will likely trump oceanic influence on future ice sheet mass loss and resulting sea level rise over centennial and longer time scales. publishedVersion |
format |
Article in Journal/Newspaper |
author |
Åkesson, Henning Morlighem, Mathieu Nisancioglu, Kerim Hestnes Svendsen, John-Inge Mangerud, Jan |
author_facet |
Åkesson, Henning Morlighem, Mathieu Nisancioglu, Kerim Hestnes Svendsen, John-Inge Mangerud, Jan |
author_sort |
Åkesson, Henning |
title |
Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet |
title_short |
Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet |
title_full |
Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet |
title_fullStr |
Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet |
title_full_unstemmed |
Atmosphere-driven ice sheet mass loss paced by topography: Insights from modelling the south-western Scandinavian Ice Sheet |
title_sort |
atmosphere-driven ice sheet mass loss paced by topography: insights from modelling the south-western scandinavian ice sheet |
publisher |
Elsevier |
publishDate |
2018 |
url |
https://hdl.handle.net/1956/18162 https://doi.org/10.1016/j.quascirev.2018.07.004 |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_source |
Quaternary Science Reviews 195 32-47 |
op_relation |
Deglaciation of the Norwegian fjords urn:issn:0277-3791 https://hdl.handle.net/1956/18162 https://doi.org/10.1016/j.quascirev.2018.07.004 cristin:1597933 |
op_rights |
Attribution CC BY-NC-ND http://creativecommons.org/licenses/by-nc-nd/4.0/ Copyright 2018 The Author(s) |
op_doi |
https://doi.org/10.1016/j.quascirev.2018.07.004 |
container_title |
Quaternary Science Reviews |
container_volume |
195 |
container_start_page |
32 |
op_container_end_page |
47 |
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1766029888846823424 |