Effect of the Spatial Variability of Physical Parameters on the Rheology of Temperate Glaciers
and Their Modelled Response to Climate Change
Best estimates by the IPCC indicate that global sea level has risen by
6.5 cm over the past century, as a consequence of thinning of the world’s ice masses.
In light of these changes, and continued warming, the primary task of glaciologists
is to predict how ice masses will respond to future climate change. Dynamic, spatially
distributed models of ice-mass motion, which calculate the deformation rate of ice under
stress, are the most effective way by which such predictions are made. However the
performance of these models are limited by their incorporation of spatial variations
in the rate at which ice responds to applied stresses, but knowledge of the 3D structure
of ice masses is currently poor. This limitation is of greatest concern on temperate valley
glaciers and small ice caps, which together have accounted for nearly two-thirds of the
observed sea-level rise over the past century, as a consequence of their dramatic retreat.
This project aims to address the current lack of knowledge concerning the structure of temperate valley
glaciers, using a multi-disciplinary research programme, in order to develop a model of valley glacier flow
that can predict and incorporate layers of different ice rheology. There are two components:
1) To determine the variability in ice properties which are important controls on rheology at the
temperate valley glacier: Glacier de Tsanfleuron, Switzerland. This is being achieved using a
combined field, laboratory and theoretical study.
2) To develop a model, which associates different rheological units with their large-scale glaciological
controls, and to generalise this information to other glaciers.
Images of Glacier de Tsanfleuron
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View approximately north above the glacier. Glacier is behind the photo
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View east (down-glacier) from glacier, August 2005
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En-route to glacier, spring 2004
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Glacier de Tsanfleuron; dusk, spring 2004
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Glacier de Tsanfleuron, August 2005
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Glacier de Tsanfleuron, spring 2004
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Principal and co-investigators
Post-doctoral research fellows
Three field seasons have been carried out to date: spring 2004, spring 2005 and summer 2005.
In the two spring seasons, surface radar data were collected along the lines shown in Figure 1.
Figure 1: Basemap of Glacier de Tsanfleuron, showing GPR tracks. Blue line shows location of survey in spring 2004.
Green and red tracks show the location of surveys in spring 2005.
Borehole radar data were collected in spring 2004 and summer 2005. These data are still being processed.
