Thermomechanical modelling of the Scandinavian ice sheet: implications for ice-stream formation

This work attempts to explain the fan-like landform assemblages observed in satellite images of the area covered by the former Scandinavian ice sheet (SIS). These assemblages have been interpreted as evidence of large ice streams within the SIS. If this interpretation is correct, then it calls into...

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Bibliographic Details
Published in:Annals of Glaciology
Main Authors: Payne, AJ, Baldwin, DJ
Format: Article in Journal/Newspaper
Language:English
Published: 1999
Subjects:
Online Access:http://hdl.handle.net/1983/1166
https://research-information.bris.ac.uk/en/publications/fe9ba96a-1fa1-40e6-9ca0-1968d7ceb8b5
https://doi.org/10.3189/172756499781821733
https://research-information.bris.ac.uk/ws/files/3006328/s13.pdf
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Summary:This work attempts to explain the fan-like landform assemblages observed in satellite images of the area covered by the former Scandinavian ice sheet (SIS). These assemblages have been interpreted as evidence of large ice streams within the SIS. If this interpretation is correct, then it calls into doubt current theories on the formation of ice streams. These theories regard soft sediment and topographic troughs as being the key determinants of ice-stream location. Neither can be used to explain the existence of ice streams on the flat, hard-rock area of the Baltic Shield. Initial results from a three-dimensional, thermomechanical ice-sheet model indicate that interactions between ice flow, form and temperature can create patterns similar to those mentioned above. The model uses a realistic, 20 km resolution gridded topography and a simple parameterization of accumulation and ablation. It produces patterns of maximum ice-sheet extent, which are similar to those reconstructed from the area's glacial geomorphology. Flow in the maximum, equilibrium ice sheet is dominated by wedges of warm, low-viscosity, fast-flowing ice. These are separated by areas of cold, slow-flowing ice. This patterning appears to develop spontaneously as the modelled ice sheet grows.