Greenland ice-stream dynamics: short-lived and agile?
Reliable knowledge of ice discharge dynamics for the Greenland ice sheet via its ice streams is essential if we are to understand its stability under future climate scenarios as well as their dynamics in the past, especially when using numerical models for diagnosis and prediction. Currently active...
Main Authors: | , , , , , , , , , , , |
---|---|
Format: | Conference Object |
Language: | unknown |
Published: |
2023
|
Subjects: | |
Online Access: | https://epic.awi.de/id/eprint/58236/ https://epic.awi.de/id/eprint/58236/1/EGU23-6770-print.pdf https://hdl.handle.net/10013/epic.43e33a48-00cc-49c5-ae3a-67bbcf8eb997 |
id |
ftawi:oai:epic.awi.de:58236 |
---|---|
record_format |
openpolar |
spelling |
ftawi:oai:epic.awi.de:58236 2024-02-11T10:04:10+01:00 Greenland ice-stream dynamics: short-lived and agile? Eisen, Olaf Franke, Steven Bons, Paul D Westhoff, Julien Weikusat, Ilka Binder, Tobias Streng, Kyra Steinhage, Daniel Helm, Veit Paden, John D Eagles, Graeme Jansen, Daniela 2023-04-23 application/pdf https://epic.awi.de/id/eprint/58236/ https://epic.awi.de/id/eprint/58236/1/EGU23-6770-print.pdf https://hdl.handle.net/10013/epic.43e33a48-00cc-49c5-ae3a-67bbcf8eb997 unknown https://epic.awi.de/id/eprint/58236/1/EGU23-6770-print.pdf Eisen, O. orcid:0000-0002-6380-962X , Franke, S. orcid:0000-0001-8462-4379 , Bons, P. D. , Westhoff, J. , Weikusat, I. orcid:0000-0002-3023-6036 , Binder, T. , Streng, K. , Steinhage, D. orcid:0000-0003-4737-9751 , Helm, V. orcid:0000-0001-7788-9328 , Paden, J. D. , Eagles, G. orcid:0000-0001-5325-0810 and Jansen, D. orcid:0000-0002-4412-5820 (2023) Greenland ice-stream dynamics: short-lived and agile? doi:10.5194/egusphere-egu23-6770 <https://doi.org/10.5194/egusphere-egu23-6770> , hdl:10013/epic.43e33a48-00cc-49c5-ae3a-67bbcf8eb997 EPIC3 Conference NonPeerReviewed 2023 ftawi 2024-01-22T00:23:15Z Reliable knowledge of ice discharge dynamics for the Greenland ice sheet via its ice streams is essential if we are to understand its stability under future climate scenarios as well as their dynamics in the past, especially when using numerical models for diagnosis and prediction. Currently active ice streams in Greenland have been well mapped using remote-sensing data while past ice-stream paths in what are now deglaciated regions can be reconstructed from the landforms they left behind. However, little is known about possible former and now defunct ice streams in areas still covered by ice. Here we use radio-echo sounding data to decipher the regional ice-flow history of the northeastern Greenland ice sheet on the basis of its internal stratigraphy. By creating a three-dimensional reconstruction of time-equivalent horizons, we map folds deep below the surface that we then attribute to the deformation caused by now-extinct ice streams. We propose that locally this ancient ice-!ow regime was much more focused and reached much farther inland than today’s and was deactivated when the main drainage system was reconfigured and relocated southwards. The insight that major ice streams in Greenland might start, shift or abruptly disappear will affect our approaches to understanding and modelling the past or future response of Earth’s ice sheets to global warming. Such behaviour has to be sufficiently reproduced by numerical models operating on the mid- to longer-term timescales to be considered adequate physical representations of the naturally occuring dynamic behaviour of ice streams. Conference Object Greenland Ice Sheet Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Greenland |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Reliable knowledge of ice discharge dynamics for the Greenland ice sheet via its ice streams is essential if we are to understand its stability under future climate scenarios as well as their dynamics in the past, especially when using numerical models for diagnosis and prediction. Currently active ice streams in Greenland have been well mapped using remote-sensing data while past ice-stream paths in what are now deglaciated regions can be reconstructed from the landforms they left behind. However, little is known about possible former and now defunct ice streams in areas still covered by ice. Here we use radio-echo sounding data to decipher the regional ice-flow history of the northeastern Greenland ice sheet on the basis of its internal stratigraphy. By creating a three-dimensional reconstruction of time-equivalent horizons, we map folds deep below the surface that we then attribute to the deformation caused by now-extinct ice streams. We propose that locally this ancient ice-!ow regime was much more focused and reached much farther inland than today’s and was deactivated when the main drainage system was reconfigured and relocated southwards. The insight that major ice streams in Greenland might start, shift or abruptly disappear will affect our approaches to understanding and modelling the past or future response of Earth’s ice sheets to global warming. Such behaviour has to be sufficiently reproduced by numerical models operating on the mid- to longer-term timescales to be considered adequate physical representations of the naturally occuring dynamic behaviour of ice streams. |
format |
Conference Object |
author |
Eisen, Olaf Franke, Steven Bons, Paul D Westhoff, Julien Weikusat, Ilka Binder, Tobias Streng, Kyra Steinhage, Daniel Helm, Veit Paden, John D Eagles, Graeme Jansen, Daniela |
spellingShingle |
Eisen, Olaf Franke, Steven Bons, Paul D Westhoff, Julien Weikusat, Ilka Binder, Tobias Streng, Kyra Steinhage, Daniel Helm, Veit Paden, John D Eagles, Graeme Jansen, Daniela Greenland ice-stream dynamics: short-lived and agile? |
author_facet |
Eisen, Olaf Franke, Steven Bons, Paul D Westhoff, Julien Weikusat, Ilka Binder, Tobias Streng, Kyra Steinhage, Daniel Helm, Veit Paden, John D Eagles, Graeme Jansen, Daniela |
author_sort |
Eisen, Olaf |
title |
Greenland ice-stream dynamics: short-lived and agile? |
title_short |
Greenland ice-stream dynamics: short-lived and agile? |
title_full |
Greenland ice-stream dynamics: short-lived and agile? |
title_fullStr |
Greenland ice-stream dynamics: short-lived and agile? |
title_full_unstemmed |
Greenland ice-stream dynamics: short-lived and agile? |
title_sort |
greenland ice-stream dynamics: short-lived and agile? |
publishDate |
2023 |
url |
https://epic.awi.de/id/eprint/58236/ https://epic.awi.de/id/eprint/58236/1/EGU23-6770-print.pdf https://hdl.handle.net/10013/epic.43e33a48-00cc-49c5-ae3a-67bbcf8eb997 |
geographic |
Greenland |
geographic_facet |
Greenland |
genre |
Greenland Ice Sheet |
genre_facet |
Greenland Ice Sheet |
op_source |
EPIC3 |
op_relation |
https://epic.awi.de/id/eprint/58236/1/EGU23-6770-print.pdf Eisen, O. orcid:0000-0002-6380-962X , Franke, S. orcid:0000-0001-8462-4379 , Bons, P. D. , Westhoff, J. , Weikusat, I. orcid:0000-0002-3023-6036 , Binder, T. , Streng, K. , Steinhage, D. orcid:0000-0003-4737-9751 , Helm, V. orcid:0000-0001-7788-9328 , Paden, J. D. , Eagles, G. orcid:0000-0001-5325-0810 and Jansen, D. orcid:0000-0002-4412-5820 (2023) Greenland ice-stream dynamics: short-lived and agile? doi:10.5194/egusphere-egu23-6770 <https://doi.org/10.5194/egusphere-egu23-6770> , hdl:10013/epic.43e33a48-00cc-49c5-ae3a-67bbcf8eb997 |
_version_ |
1790600709140381696 |