Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles
Hanyk et al. (2005) studied the viscous shear heating in the mantle induced by the surface loading and unloading of a parabolic-shaped Laurentide-size ice sheet. They found that for linear rheology, viscous heating is mainly concentrated below the ice sheet. The depth extent of the heating in the ma...
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ftunivhongkonghu:oai:hub.hku.hk:10722/241054 2023-05-15T16:40:13+02:00 Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles van der Wal, W Wu, PPC Huang, P 2017 http://hdl.handle.net/10722/241054 eng eng European Geoscience Union General Assembly, EGU 2017 The 2017 General Assembly of the European Geosciences Union (EGU), Vienna, Austria, 23–28 April 2017. 272195 http://hdl.handle.net/10722/241054 Conference_Paper 2017 ftunivhongkonghu 2023-01-14T16:19:31Z Hanyk et al. (2005) studied the viscous shear heating in the mantle induced by the surface loading and unloading of a parabolic-shaped Laurentide-size ice sheet. They found that for linear rheology, viscous heating is mainly concentrated below the ice sheet. The depth extent of the heating in the mantle is determined by the viscosity distribution. Also, the magnitude of viscous heating is significantly affected by the rate of ice thickness change. However, only one ice sheet has been considered in their work and the interactions between ice sheets and ocean loading have been neglected. Furthermore, only linear rheology has been considered, although they suggested that non-Newtonian rheology may have a stronger effect. Here we follow Hanyk et al. (2005) and computed the viscous dissipation for viscoelastic models using the finite element methodology of Wu (2004) and van der Wal et al. (2010). However, the global ICE6G model (Peltier et al. 2015) with realistic oceans is used here to provide the surface loading. In addition, viscous heating in nonlinear rheology, composite rheology, in addition to linear rheology with uniform or VM5a profile are computed and compared. Our results for linear rheology mainly confirm the findings of Hanyk et al. (2005). For both non-linear and composite rheologies, viscous heating is also mainly distributed near and under the ice sheets, but, more concentrated; depending on the horizontal dimension of the ice sheet, it can extend into the lower mantle, but for some of the time, not as deep as that for linear rheology. For composite rheology, the viscous heating is dominated by the effect of non-linear relation between the stress and the strain. The ice history controls the time when the local maximum in viscous heating appears. However, the magnitude of the viscous heating is affected by mantle rheology as well as the ice loading. Due to viscosity stratification, the shape of the region with high viscous heating in model VM5a is a little more irregular than that from uniform ... Conference Object Ice Sheet University of Hong Kong: HKU Scholars Hub Peltier ENVELOPE(-63.495,-63.495,-64.854,-64.854) |
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Open Polar |
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University of Hong Kong: HKU Scholars Hub |
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ftunivhongkonghu |
language |
English |
description |
Hanyk et al. (2005) studied the viscous shear heating in the mantle induced by the surface loading and unloading of a parabolic-shaped Laurentide-size ice sheet. They found that for linear rheology, viscous heating is mainly concentrated below the ice sheet. The depth extent of the heating in the mantle is determined by the viscosity distribution. Also, the magnitude of viscous heating is significantly affected by the rate of ice thickness change. However, only one ice sheet has been considered in their work and the interactions between ice sheets and ocean loading have been neglected. Furthermore, only linear rheology has been considered, although they suggested that non-Newtonian rheology may have a stronger effect. Here we follow Hanyk et al. (2005) and computed the viscous dissipation for viscoelastic models using the finite element methodology of Wu (2004) and van der Wal et al. (2010). However, the global ICE6G model (Peltier et al. 2015) with realistic oceans is used here to provide the surface loading. In addition, viscous heating in nonlinear rheology, composite rheology, in addition to linear rheology with uniform or VM5a profile are computed and compared. Our results for linear rheology mainly confirm the findings of Hanyk et al. (2005). For both non-linear and composite rheologies, viscous heating is also mainly distributed near and under the ice sheets, but, more concentrated; depending on the horizontal dimension of the ice sheet, it can extend into the lower mantle, but for some of the time, not as deep as that for linear rheology. For composite rheology, the viscous heating is dominated by the effect of non-linear relation between the stress and the strain. The ice history controls the time when the local maximum in viscous heating appears. However, the magnitude of the viscous heating is affected by mantle rheology as well as the ice loading. Due to viscosity stratification, the shape of the region with high viscous heating in model VM5a is a little more irregular than that from uniform ... |
format |
Conference Object |
author |
van der Wal, W Wu, PPC Huang, P |
spellingShingle |
van der Wal, W Wu, PPC Huang, P Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles |
author_facet |
van der Wal, W Wu, PPC Huang, P |
author_sort |
van der Wal, W |
title |
Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles |
title_short |
Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles |
title_full |
Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles |
title_fullStr |
Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles |
title_full_unstemmed |
Effect of Mantle Rheology on Viscous Heating induced during Ice Sheet Cycles |
title_sort |
effect of mantle rheology on viscous heating induced during ice sheet cycles |
publishDate |
2017 |
url |
http://hdl.handle.net/10722/241054 |
long_lat |
ENVELOPE(-63.495,-63.495,-64.854,-64.854) |
geographic |
Peltier |
geographic_facet |
Peltier |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
European Geoscience Union General Assembly, EGU 2017 The 2017 General Assembly of the European Geosciences Union (EGU), Vienna, Austria, 23–28 April 2017. 272195 http://hdl.handle.net/10722/241054 |
_version_ |
1766030603215437824 |