Elmer/Ice Ice Sheet Model

Elmer/Ice is an ologo elmer ICEpen-source high-fidelity ice dynamic code developed at CSC-IT Center of Science. It utilizes the Finite Element Method and doesn’t apply any simplifications in terms of neglected stress components, which makes it applicable to glaciological problems where common ice-sheet codes are unable to capture the physics of steeply inclined or marine terminated glaciers.

Animation of temporal evolution (=retreat) of Midtre Lovénbreen from 1977 to 2050. Credits CSC/Artic Centre (T. Zwinger,/J.C.Moore, simulation/data), CSC (J.Hokkanen, visualisation)

Reference

Gagliardini, O., T. Zwinger, F. Gillet-Chaulet, G. Durand, L. Favier, B. de Fleurian, R. Greve, M. Malinen, C. Martín, P. Råback, J. Ruokolainen, M. Sacchettini, M. Schäfer, H. Seddik, and J. Thies, 2013. Capabilities and performance of Elmer/Ice, a new-generation ice sheet model, Geosci. Model Dev., 6, 1299-1318, doi:10.5194/gmd-6-1299-2013.

Elmer/Ice support for continuation and finalization of SVALI projects

eSTICC contributed to unfinished activities from the NCoE SVALI by continuing and finalizing the  projects listed below. Those activities were mainly focused around the high-fidelity ice sheet model Elmer/Ice. Most of these projects helped to finalize the PhD studies of students that either were working within or were supported by SVALI.

Determining dynamics of calving at Kronebreen

Kronebreen slidingeSTICC contributed to two publications for the PhD thesis of Dorothée Vallot, an associated SVALI-student. Bith focused on the fasted outlet glacier on Svalbard, Kronebreen. The studies used Elmer/Ice and Elmer/Ice amongst other models that were constrained and driven by field and remote sensing data. Papers published are

Vallot, D., J. Åström, T. Zwinger, R. Pettersson, A. Everett, D.I. Benn, A. Luckman, W.J.J. van Pelt, F. Nick, and J. Kohler, 2018. Effects of undercutting and sliding on calving: a global approach applied to Kronebreen, Svalbard. The Cryosphere, 12, 609-625, doi:10.5194/tc-12-609-2018

Vallot, D., R. Pettersson, A. Luckman, D. Benn, T. Zwinger, W.J.J. van Pelt, J. Kohler, M. Schäfer, B. Claremar and N.R.J. Hulton, 2017. Basal dynamics of Kronebreen, a fast-flowing tidewater glacier in Svalbard: Non-local spatio-temporal response to water input, Journal of Glaciology, 1-13, doi:doi:10.1017/jog.2017.69.

A case study on influence of water pressure in sub-glacial channels on ice dynamics

pim2018The sub-glacial laboratory at Engabreen, Norway was a major study site in the SVALI-NCoE project. SVALI PhD-student Pierre-Marie Lefeuvre investigated stress distribution changes using Elmer/Ice linking those to data recorded with the pressure sensors installed at the lab, resulting in the following publication

Lefeuvre P.-M., T. Zwinger, M. Jackson, O. Gagliardini, G. Lappegard and J.O. Hagen, 2018. Stress Redistribution Explains Anti-correlated Subglacial Pressure Variations. Front. Earth Sci. 5:110. doi:10.3389/feart.2017.00110

Classification of different calving modes

TBennJGlac2017 picturehis was a project study on calving law parametrization using a combined model approach of Elmer/Ice  (continuum model) and a discrete particle model, HiDEM. This was performed in order to find out calving parametrisations for continuum models. The corresponding publication is

Benn, D.I., J. Åström, T. Zwinger, J. Todd, F.M. Nick, S. Cook, N.R.J. Hulton, and A. Luckman, 2017. Melt-under-cutting and buoyancy-driven calving from tidewater glaciers: new insights from discrete element and continuum model simulations, Journal of Glaciology, 1-12, doi:10.1017/jog.2017.41.

Investigation of a rapidly rising jökulhlaup

Mesh of Elmer/Ice of the Skáfta cauldron
Meshed geometry of Skaftá cauldron approximated by cylindrical coordinates

This is a study on interaction of sudden subglacial water drainage (jökulhlaup) on ice mechanics based on a real case in Iceland, combining in a nice way data that was obtained during SVALI NCoE and modelling using Elmer/Ice. This was in direct support of the PhD thesis from SVALI student Bergur Einarson. The corresponding publication is

Einarsson, B., T. Jóhannesson, T. Thorsteinsson, E. Gaidos, and T. Zwinger, 2017. Subglacial flood path development during a rapidly rising jökulhlaup from the western Skaftá cauldron, Vatnajökull, Iceland, Journal of Glaciology, 1-13, doi:10.1017/jog.2017.33.

Determining surface mass balance from DEM’s

Accum all annotThis is a study on inverse determination of past surface mass balance from a series of digital elevation models using the ice flow model Elmer/Ice, thus a combination of data and modelling. It is a direct contribution to the PhD thesis of SVALI student Ilona Välisuo.  The corresponding publication is

 Välisuo, I., T. Zwinger and J. Kohler, 2017. Inverse solution of surface mass balance of Midtre Lovénbreen, Svalbard, Journal of Glaciology, 1-10, doi:10.1017/jog.2017.26.

Investigation of pre-surge dynamics at Basin 3, Austfonna

Deep crevasses computed by HiDEM  and sub-glacial water routes underneath Basin 3

A detailed study on the processes that lead to the surge of Basin 3 on Austfonna, Svalbard using Elmer/Ice in combination with other models (BISICLES and HiDEM) resulted in two publications that contributed to the successful PhD thesis of SVALI student Yongmei Gong

Gong, Y., T. Zwinger, S. Cornford, R. Gladstone, M. Schäfer, and J.C. Moore, 2016. Importance of basal boundary conditions in transient simulations: case study of a surging marine-terminating glacier on Austfonna, Svalbard, Journal of Glaciology, pp. 1–12, doi:10.1017/jog.2016.121.

Gong, Y., Zwinger, T., Åström, J., Altena, B., Schellenberger, T., Gladstone, R., and Moore, J. C., 2018. Simulating the roles of crevasse routing of surface water and basal friction on the surge evolution of Basin 3, Austfonna ice cap. The Cryosphere, 12, 1563-1577, doi:10.5194/tc-12-1563-2018

Combination: SIA and full-Stokes

Regions of SIA (blue) and FS (red) in the ISCAL computation of Greenland Ice sheet

A SVALI-supported study of a special hybrid ice-sheet algorithm combining shallow ice approximation (SIA) and unaltered Stokes (full Stokes = FS) solution. The corresponding publication is

Ahlkrona, J., P. Lötstedt, N. Kirchner, and T. Zwinger, 2016. Dynamically coupling the non-linear Stokes equations with the shallow ice approximation in glaciology: Description and first applications of the ISCAL method. J. Comp. Phys., 308, 1-19, doi:10.1016/j.jcp.2015.12.025.