Modeling Northern Hemispheric ice sheet dynamics, sea level change and solid Earth deformation through the last glacial cycle

<p>The interaction between ice sheets and the solid Earth plays an important role for ice-sheet stability and sea-level change and hence for global climate models. Glacial-isostatic adjustment (GIA) models enable simulation of the solid Earth response due to variations in ice-sheet and ocean loading and prediction of the relative sea-level change. Because the viscoelastic response of the solid Earth depends on both ice-sheet distribution and the Earth&#8217;s rheology, independent constraints for the Earth structure in GIA models are beneficial. Seismic tomography models facilitate insights into the Earth&#8217;s interior, revealing lateral variability of the mantle viscosity that allows studying its relevance in GIA modeling. Especially, in regions of low mantle viscosity, the predicted surface deformations generated with such 3D GIA models differ considerably from those generated by traditional GIA models with radially symmetric structures. But also, the conversion from seismic velocity variations to viscosity is affected by a set of uncertainties. Here, we apply geodynamically constrained 3D Earth structures. We analyze the impact of conversion parameters (reduction factor in Arrhenius law and radial viscosity profile) on relative sea-level predictions. Furthermore, we focus on exemplary low-viscosity regions like the Cascadian subduction zone and southern Patagonia, which coincide with significant ice-mass changes.</p>

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Past Antarctic ice sheet dynamics (PAIS) and implications for future sea-level change

10.1016/b978-0-12-819109-5.00010-4 ◽

2022 ◽

pp. 689-768

Author(s):

Florence Colleoni ◽

Laura De Santis ◽

Tim R. Naish ◽

Robert M. DeConto ◽

Carlota Escutia ◽

...

Keyword(s):

Sea Level ◽

Ice Sheet ◽

Sea Level Change ◽

Antarctic Ice Sheet ◽

Level Change ◽

Ice Sheet Dynamics

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Into and out of the Last Glacial Maximum: sea-level change during Oxygen Isotope Stages 3 and 2

Quaternary Science Reviews ◽

10.1016/s0277-3791(01)00071-3 ◽

2002 ◽

Vol 21 (1-3) ◽

pp. 343-360 ◽

Cited By ~ 464

Author(s):

Kurt Lambeck ◽

Yusuke Yokoyama ◽

Tony Purcell

Keyword(s):

Oxygen Isotope ◽

Sea Level ◽

Last Glacial Maximum ◽

Sea Level Change ◽

Glacial Maximum ◽

Last Glacial ◽

Level Change ◽

The Last Glacial Maximum ◽

The Last Glacial

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Ice-sheet modelling characteristics in sea-level-based temperature reconstructions over the last glacial cycle

Journal of Glaciology ◽

10.3189/172756506781828944 ◽

2006 ◽

Vol 52 (176) ◽

pp. 149-158 ◽

Cited By ~ 3

Author(s):

Frank Wilschut ◽

Richard Bintanja ◽

Roderik S.W. Van De Wal

Keyword(s):

Sea Level ◽

Sediment Cores ◽

Ice Sheet ◽

Ice Cores ◽

Glacial Cycle ◽

Deep Sea Sediment ◽

Last Glacial ◽

Proxy Records ◽

Temperature Reconstructions ◽

The Last Glacial

AbstractA widely used method for investigating palaeotemperatures is to analyze local proxy records (e.g. ice cores or deep-sea sediment cores). The interpretation of these records is often not straightforward, and global or hemispheric means cannot be deduced from local estimates because of large spatial variability. Using a different approach, temperature changes over the last glacial cycle can be estimated from sea-level observations by applying an inverse method to an ice-sheet model. In order to understand the underlying physical mechanisms, we used a 1-D ice-sheet model and a 3-D coupled thermodynamic ice-sheet–ice-shelf–bedrock model to investigate the importance of several physical processes for the inverse temperature reconstructions. Results show that (i) temperature reconstructions are sensitive to the employed formulation of mass balance, (ii) excluding thermodynamics in the ice sheet leads to a smaller temperature amplitude in the reconstruction and (iii) hysteresis in the non-linear relation between sea level and temperature occurs as a consequence of ice redistribution in the process of merging and separation of ice sheets. The ice redistribution does not occur if the geometry does not support the formation of a relatively flat dome, which tends to be preserved in warming conditions.

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