HUSCAP logo Hokkaido Univ. logo

Hokkaido University Collection of Scholarly and Academic Papers >
Institute of Low Temperature Science >
Peer-reviewed Journal Articles, etc >

Permanent fast flow versus cyclic surge behaviour: numerical simulations of the Austfonna ice cap, Svalbard

Files in This Item:
Dunse_etal_2011_JGlac.pdf1.05 MBPDFView/Open
Please use this identifier to cite or link to this item:http://hdl.handle.net/2115/47983

Title: Permanent fast flow versus cyclic surge behaviour: numerical simulations of the Austfonna ice cap, Svalbard
Authors: Dunse, Thorben Browse this author
Greve, Ralf Browse this author →KAKEN DB
Schuler, Thomas Vikhamar Browse this author
Hagen, Jon Ove Browse this author
Keywords: Austfonna
Ice cap
Surge
Oscillation
Modelling
Issue Date: 1-Apr-2011
Publisher: International Glaciological Society
Journal Title: Journal of Glaciology
Volume: 57
Issue: 202
Start Page: 247
End Page: 259
Publisher DOI: 10.3189/002214311796405979
Abstract: A large part of the ice flux within ice caps occurs through spatially limited fast-flowing units. Some of them permanently maintain fast flow, whereas others operate in an oscillatory mode, characterized by short-lived active phases followed by long quiescent phases. This surge-type behaviour results from intrinsic rather than external factors, thus complicating estimates of glacier response to climate change. Here we present numerical model results from Austfonna, an ice cap on Svalbard that comprises several surge-type basins. Previous studies have suggested a thermally controlled soft-bed surge mechanism for Svalbard. We systematically change the parameters that govern the nature of basal motion and thereby control the transition between permanent and oscillatory fast flow. Surge-type behaviour is realized by a relatively abrupt onset of basal sliding when basal temperatures approach the pressure-melting point and enhanced sliding of marine grounded ice. Irrespective of the dynamic regime, the absence of considerable volumes of temperate ice, both in the observed and simulated ice cap, indicates that fast flow is accomplished by basal motion over a temperate bed. Given an idealized present-day climate, the equilibrium ice-cap size varies significantly, depending on the chosen parameters.
Rights: © 2011 International Glaciological Society
Relation: http://www.igsoc.org/
Type: article
URI: http://hdl.handle.net/2115/47983
Appears in Collections:低温科学研究所 (Institute of Low Temperature Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)

Submitter: Greve Ralf

Export metadata:

OAI-PMH ( junii2 , jpcoar )


 

Feedback - Hokkaido University