Journal cover Journal topic
The Cryosphere An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 4.790 IF 4.790
  • IF 5-year value: 5.921 IF 5-year
    5.921
  • CiteScore value: 5.27 CiteScore
    5.27
  • SNIP value: 1.551 SNIP 1.551
  • IPP value: 5.08 IPP 5.08
  • SJR value: 3.016 SJR 3.016
  • Scimago H <br class='hide-on-tablet hide-on-mobile'>index value: 63 Scimago H
    index 63
  • h5-index value: 51 h5-index 51
Volume 10, issue 6
The Cryosphere, 10, 2865-2886, 2016
https://doi.org/10.5194/tc-10-2865-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.

Special issue: The evolution of permafrost in mountain regions

The Cryosphere, 10, 2865-2886, 2016
https://doi.org/10.5194/tc-10-2865-2016
© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 23 Nov 2016

Research article | 23 Nov 2016

Rock glaciers on the run – understanding rock glacier landform evolution and recent changes from numerical flow modeling

Johann Müller, Andreas Vieli, and Isabelle Gärtner-Roer Johann Müller et al.
  • Department of Geography, University of Zurich, Zurich, 8004, Switzerland

Abstract. Rock glaciers are landforms that form as a result of creeping mountain permafrost which have received considerable attention concerning their dynamical and thermal changes. Observed changes in rock glacier motion on seasonal to decadal timescales have been linked to ground temperature variations and related changes in landform geometries interpreted as signs of degradation due to climate warming. Despite the extensive kinematic and thermal monitoring of these creeping permafrost landforms, our understanding of the controlling factors remains limited and lacks robust quantitative models of rock glacier evolution in relation to their environmental setting.

Here, we use a holistic approach to analyze the current and long-term dynamical development of two rock glaciers in the Swiss Alps. Site-specific sedimentation and ice generation rates are linked with an adapted numerical flow model for rock glaciers that couples the process chain from material deposition to rock glacier flow in order to reproduce observed rock glacier geometries and their general dynamics. Modeling experiments exploring the impact of variations in rock glacier temperature and sediment–ice supply show that these forcing processes are not sufficient to explain the currently observed short-term geometrical changes derived from multitemporal digital terrain models at the two different rock glaciers. The modeling also shows that rock glacier thickness is dominantly controlled by slope and rheology while the advance rates are mostly constrained by rates of sediment–ice supply. Furthermore, timescales of dynamical adjustment are found to be strongly linked to creep velocity. Overall, we provide a useful modeling framework for a better understanding of the dynamical response and morphological changes of rock glaciers to changes in external forcing.

Publications Copernicus
Special issue
Download
Short summary
Rock glaciers are landforms indicative of permafrost creep and received considerable attention concerning their dynamical and thermal changes. We use a holistic approach to analyze and model the current and long-term dynamical development of two rock glaciers in the Swiss Alps. The modeling results show the impact of variations in temperature and sediment–ice supply on rock glacier evolution and describe proceeding signs of degradation due to climate warming.
Rock glaciers are landforms indicative of permafrost creep and received considerable attention...
Citation
Share