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

Journal metrics

Journal metrics

  • IF value: 4.524 IF 4.524
  • IF 5-year value: 5.558 IF 5-year 5.558
  • CiteScore value: 4.84 CiteScore 4.84
  • SNIP value: 1.425 SNIP 1.425
  • SJR value: 3.034 SJR 3.034
  • IPP value: 4.65 IPP 4.65
  • h5-index value: 52 h5-index 52
  • Scimago H index value: 55 Scimago H index 55
Discussion papers
https://doi.org/10.5194/tc-2018-192
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-2018-192
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 20 Nov 2018

Research article | 20 Nov 2018

Review status
This discussion paper is a preprint. It is a manuscript under review for the journal The Cryosphere (TC).

Modeling Sea Ice fracture at very high resolution with VP rheologies

Damien Ringeisen1, Nils Hutter1, Martin Losch1, and L. Bruno Tremblay2 Damien Ringeisen et al.
  • 1Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar und Meeresforschung (AWI), Bremerhaven, Germany
  • 2Department of Atmospheric and Oceanic Sciences, McGill University, Montréal, Quebec, Canada

Abstract. Recent high resolution pan-Arctic sea ice simulations show fracture patterns (Linear Kinematic Features – LKFs) that are typical of granular materials but with intersection (fracture) angles wider than those observed from high-resolution satellite images (with a modal value of θ=20°). In this article, We investigate the mechanism of formation and parameter dependencies of ice fracture in simple numerical bi-axial test on a 8kmx25km ice floe at an unprecedented resolution of 25m for two different yield curves: an elliptical (VP) and a Coulombic yield curve both with normal flow rule. In the standardVP model, the simulated angle of fracture is θ=33.9°, compared to 20° in observations. The dependence of the angle of fracture on the ice shear strength is also contrary to that of typical granular materials with larger angle of fracture for higher shear strength – think of a wet sand castle with steeper walls than a dry sand castle. In this model, the divergence along the fracture lines (or LKFs) is entirely dictated by the ice shear strength used in the model with high shear strength resulting in convergence along LKFs and low shear strength resulting in divergence along LKFs. This is again contrary to typical granular materials where divergence (or dilation) is linked with the orientation of contacts normals that oppose the flow with divergence present for larger shear resistance and convergence for lower shear resistance. Moreover, the angle of fracture depends on the confining pressure in the uni-axial test with more convergence as the confining pressure increases, again contrary to granular material that have an angle of fracture that is independent of the confining pressure. We note that all three behaviors of the VP model are linked with the use of an associative (normal) flow rule. In the Coulombic model, the angle of fracture is smaller (θ=23.5°), but the solution is unstable when the compressive stresses are too large because of the discontinuity between the straight limbs of the yield curve and the elliptical capping. Our results show that while the VP model gives angles of fracture that are visually correct, the bias in the magnitude of the angle of fracture and the physical dependencies of the angle of fracture on mechanical strength parameters and stress fields couple the sea ice mechanical strength parameters, the sea-ice drift, sea-ice deformation (strain-rate) field in an inconsistent way. We consider this evidence to move away from the elliptical yield curve and associative (normal) flow rule, a deformation law that is not applicable to pressure-sensitive and dilatant granular material such as sea ice.

Damien Ringeisen et al.
Interactive discussion
Status: open (until 15 Jan 2019)
Status: open (until 15 Jan 2019)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
[Subscribe to comment alert] Printer-friendly Version - Printer-friendly version Supplement - Supplement
Damien Ringeisen et al.
Damien Ringeisen et al.
Viewed  
Total article views: 260 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
206 50 4 260 2 2
  • HTML: 206
  • PDF: 50
  • XML: 4
  • Total: 260
  • BibTeX: 2
  • EndNote: 2
Views and downloads (calculated since 20 Nov 2018)
Cumulative views and downloads (calculated since 20 Nov 2018)
Viewed (geographical distribution)  
Total article views: 253 (including HTML, PDF, and XML) Thereof 253 with geography defined and 0 with unknown origin.
Country # Views %
  • 1
1
 
 
 
 
Cited  
Saved  
No saved metrics found.
Discussed  
No discussed metrics found.
Latest update: 15 Dec 2018
Publications Copernicus
Download
Short summary
We study the creation of fracture in sea ice plastic models. To do this, we compress an ideal piece of ice of 8 by 25 kilometers at an unprecedented resolution of 25 meters. We use two different mathematical expressions defining the resistance of ice. We find that the most common one is unable to model the fracture correctly while the other gives better results but bring instabilities. The results are often in opposition with ice granular nature (like sand) and call for changes in ice modeling.
We study the creation of fracture in sea ice plastic models. To do this, we compress an ideal...
Citation
Share