Speaker
Dr
Martin Luethi
(University of Zurich, Geography)
Description
The iceberg calving process influences the geometry of a tidewater glacier,
and is in turn controlled by the terminus geometry through the stress field
which controls damage and fracture of the ice. A simple parametrization of
the stress field at the glacier terminus is obtained from the results of a
Finite Element model with varying water depths. Using this stress field in an
isotropic damage evolution equation yields calving rates in dependence of
calving front thickness and water depth. These parametrized calving rates
compare favorably with observations, and extend well established
parametrizations. The proposed calving parametrization is easy to implement
in numerical ice sheet models. Using these parametrized calving rates in a
minimal calving model allows us to analyze the intricate feedbacks of the
calving process, reproduce observed tidewater glacier dynamics, and to analyze
the stability of glacier termini.
Significance statement
This work presents a new, physics-based and experimentally validated parametrization for glacier calving. Parameters of a damage evolution law appicable to glacier ice can therefore be inferred.
Primary author
Dr
Martin Luethi
(University of Zurich, Geography)
Co-authors
Dr
Andreas Vieli
(University of Zurich)
Mr
Remy Mercenier
(University of Zurich)
