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Title
  • en A full Stokes-flow thermo-mechanical model for firn and ice applied to the Gorshkov crater glacier, Kamchatka
Creator
    • en Zwinger, Thomas
    • en Gagliardini, Olivier
    • en Shiraiwa, Takayuki
    • en Lyly, Mikko
Accessrights open access
Rights
  • en © 2007 International Glaciological Society
Subject
  • Other en Glacier
  • Other en Crater
  • Other en Volcano
  • Other en Flow
  • Other en Modelling
  • NDC 452
Description
  • Abstract en The Gorshkov crater glacier at Ushkovsky volcano, Kamchatka, is characterized by a large aspect ratio and special thermodynamic conditions at the bedrock caused by a locally enhanced and spatially varying geothermal heat flux. Furthermore, large parts of this glacier consist of firn rather than pure ice, which alters the rheological properties (such as viscosity and compressibility) of the glacier. We present a newly developed, thermo-mechanically coupled, three-dimensional flow model based on the finite-element (FE) modeling software Elmer, and apply it to the Gorshkov crater glacier. By assuming steady-state conditions, the present-day velocity field, temperature field, basal melting rate and age distribution are simulated. We find that flow velocities are generally small (10’s of centimeters per year). Horizontal and vertical velocities are of comparable magnitude, which shows that the shallow-ice approximation is not applicable. Owing to the spatially variable volcanic heat flux, the thermal regime at the ice base is cold in the deeper parts of the glacier and temperate in the shallower parts. The measured temperature profile and age horizons at the K2 borehole are reproduced quite well, and remaining discrepancies may be attributed to transient (non-steady-state) conditions. Firn compressibility is identified as a crucial element for the modeling approach.
Publisher en International Glaciological Society
Date
    Issued2007-10-01
Language
  • eng
Resource Type journal article
Version Type VoR
Identifier HDL http://hdl.handle.net/2115/34532
Relation
  • URI http://www.igsoc.org/
  • isIdenticalTo DOI https://doi.org/10.3189/172756407782282543
Journal
    • PISSN 0260-3055
    • EISSN 1727-5644
      • en Annals of Glaciology
      • Volume Number45 Page Start29 Page End37
File
Oaidate 2023-09-30