Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time
Glacial isostatic adjustment is the viscoelastic response of the earth to ice sheet loading. Ice dynamic models employ glacial isostatic adjustment to accurately simulate bedrock uplift. In previous studies, ice dynamic models use only a constant relaxation time to predict bedrock uplift. In this st...
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fttudelft:oai:tudelft.nl:uuid:372721e2-2891-48f2-8c1f-5c8dd036c3a3 2023-07-30T03:59:09+02:00 Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time oude Egbrink, Dirk (author) van der Wal, W. (mentor) Vermeersen, L.L.A. (graduation committee) de Visser, C.C. (graduation committee) van de Wal, S.W. (graduation committee) de Boer, B. (graduation committee) Delft University of Technology (degree granting institution) 2017-12-21 http://resolver.tudelft.nl/uuid:372721e2-2891-48f2-8c1f-5c8dd036c3a3 en eng http://resolver.tudelft.nl/uuid:372721e2-2891-48f2-8c1f-5c8dd036c3a3 © 2017 Dirk oude Egbrink GIA Antarctica viscosity relaxation time glacial isostatic adjustment ice sheet wavelength master thesis 2017 fttudelft 2023-07-08T20:00:51Z Glacial isostatic adjustment is the viscoelastic response of the earth to ice sheet loading. Ice dynamic models employ glacial isostatic adjustment to accurately simulate bedrock uplift. In previous studies, ice dynamic models use only a constant relaxation time to predict bedrock uplift. In this study, the aim is to improve an ice dynamic model by using a laterally varying bedrock relaxation time. Shear wave velocity data suggest a sharp increase in relaxation time between West and East Antarctica. Viscosity fields based on shear wave velocity data were converted to a set of relaxation time fields that are compatible with the ice dynamic model. These relaxation time fields were used in an ice dynamic simulation for the Antarctic Ice Sheet. It was found that largest differences between the different relaxation time models occur from 20 000 years ago up to PD. The model with a high relaxation time average showed a decrease in ice volume of 22.0%, whereas the model with a low relaxation time average, decreased by 17.4%. It was found that the largest differences between the models occurred at the WAIS due to the strong interaction of sea level and bedrock uplift. Furthermore, it was found that a reduction of ice sheet wavelength led to relaxation time decrease, locally up to 50%. This appeared to be a stabilising mechanism for decreasing ice sheets, but the effective retained ice volume by this mechanism remains unknown. Aerospace Engineering Master Thesis Antarc* Antarctic Antarctica East Antarctica Ice Sheet Delft University of Technology: Institutional Repository Antarctic East Antarctica The Antarctic |
institution |
Open Polar |
collection |
Delft University of Technology: Institutional Repository |
op_collection_id |
fttudelft |
language |
English |
topic |
GIA Antarctica viscosity relaxation time glacial isostatic adjustment ice sheet wavelength |
spellingShingle |
GIA Antarctica viscosity relaxation time glacial isostatic adjustment ice sheet wavelength oude Egbrink, Dirk (author) Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time |
topic_facet |
GIA Antarctica viscosity relaxation time glacial isostatic adjustment ice sheet wavelength |
description |
Glacial isostatic adjustment is the viscoelastic response of the earth to ice sheet loading. Ice dynamic models employ glacial isostatic adjustment to accurately simulate bedrock uplift. In previous studies, ice dynamic models use only a constant relaxation time to predict bedrock uplift. In this study, the aim is to improve an ice dynamic model by using a laterally varying bedrock relaxation time. Shear wave velocity data suggest a sharp increase in relaxation time between West and East Antarctica. Viscosity fields based on shear wave velocity data were converted to a set of relaxation time fields that are compatible with the ice dynamic model. These relaxation time fields were used in an ice dynamic simulation for the Antarctic Ice Sheet. It was found that largest differences between the different relaxation time models occur from 20 000 years ago up to PD. The model with a high relaxation time average showed a decrease in ice volume of 22.0%, whereas the model with a low relaxation time average, decreased by 17.4%. It was found that the largest differences between the models occurred at the WAIS due to the strong interaction of sea level and bedrock uplift. Furthermore, it was found that a reduction of ice sheet wavelength led to relaxation time decrease, locally up to 50%. This appeared to be a stabilising mechanism for decreasing ice sheets, but the effective retained ice volume by this mechanism remains unknown. Aerospace Engineering |
author2 |
van der Wal, W. (mentor) Vermeersen, L.L.A. (graduation committee) de Visser, C.C. (graduation committee) van de Wal, S.W. (graduation committee) de Boer, B. (graduation committee) Delft University of Technology (degree granting institution) |
format |
Master Thesis |
author |
oude Egbrink, Dirk (author) |
author_facet |
oude Egbrink, Dirk (author) |
author_sort |
oude Egbrink, Dirk (author) |
title |
Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time |
title_short |
Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time |
title_full |
Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time |
title_fullStr |
Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time |
title_full_unstemmed |
Modelling the Last Glacial Ice Sheet on Antarctica with Laterally Varying Relaxation Time |
title_sort |
modelling the last glacial ice sheet on antarctica with laterally varying relaxation time |
publishDate |
2017 |
url |
http://resolver.tudelft.nl/uuid:372721e2-2891-48f2-8c1f-5c8dd036c3a3 |
geographic |
Antarctic East Antarctica The Antarctic |
geographic_facet |
Antarctic East Antarctica The Antarctic |
genre |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet |
genre_facet |
Antarc* Antarctic Antarctica East Antarctica Ice Sheet |
op_relation |
http://resolver.tudelft.nl/uuid:372721e2-2891-48f2-8c1f-5c8dd036c3a3 |
op_rights |
© 2017 Dirk oude Egbrink |
_version_ |
1772809871199043584 |