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Université de Fribourg

A general theory of rock glacier creep based on in-situ and remote sensing observations

Cicoira, Alessandro ; Marcer, Marco ; Gärtner‐Roer, Isabelle ; Bodin, Xavier ; Arenson, Lukas U. ; Vieli, Andreas

In: Permafrost and Periglacial Processes, 2020, vol. 32, no. 1, p. 139-153

The ongoing acceleration in rock glacier velocities concurrent with increasing air temperatures, and the widespread onset of rock glacier destabilization have reinforced the interest in rock glacier dynamics and in its coupling to the climate system. Despite the increasing number of studies investigating this phenomenon, our knowledge of both the fundamental mechanisms controlling rock...

Université de Fribourg

Reversed surface-mass-balance gradients on himalayan debris-covered glaciers inferred from remote sensing

Bisset, Rosie R. ; Dehecq, Amaury ; Goldberg, Daniel N. ; Huss, Matthias ; Bingham, Robert G. ; Gourmelen, Noel

In: Remote Sensing, 2020, vol. 12, no. 10, p. 1563

Meltwater from the glaciers in High Mountain Asia plays a critical role in water availability and food security in central and southern Asia. However, observations of glacier ablation and accumulation rates are limited in spatial and temporal scale due to the challenges that are associated with fieldwork at the remote, high-altitude settings of these glaciers. Here, using a...

Université de Fribourg

The impact of climate change and glacier mass loss on the hydrology in the Mont-Blanc massif

Laurent, Léa ; Buoncristiani, Jean‑François ; Pohl, Benjamin ; Zekollari, Harry ; Farinotti, Daniel ; Huss, Matthias ; Mugnier, Jean‑Louis ; Pergaud, Julien

In: Scientific Reports, 2020, vol. 10, no. 1, p. 10420

The Mont-Blanc massif, being iconic with its large glaciers and peaks of over 4,000 m, will experience a sharp increase in summer temperatures during the twenty-first century. By 2100, the impact of climate change on the cryosphere and hydrosphere in the Alps is expected to lead to a decrease in annual river discharge. In this work, we modelled the twenty-first century evolution of runoff in...

Université de Fribourg

Estimating glacier-bed overdeepenings as possible sites of future lakes in the de-glaciating Mont Blanc massif (Western European Alps)

Magnin, F. ; Haeberli, W. ; Linsbauer, Andreas ; Deline, P. ; Ravanel, L.

In: Geomorphology, 2020, vol. 350, p. 106913

De-glaciating high mountain areas result in new landscapes of bedrock and debris where permafrost can degrade, persist or even newly form in cases, and of new lakes in glacier bed overdeepenings (GBOs) becoming ice-free. These landscapes with new lakes in close neighborhood to over-steepened and perennially frozen slopes are prone to chain reaction processes (e.g. rock-ice avalanches into...

Université de Fribourg

Potential future lakes from continued glacier shrinkage in the Aosta Valley Region (Western Alps, Italy)

Viani, Cristina ; Machguth, Horst ; Huggel, Christian ; Godio, Alberto ; Franco, Diego ; Perotti, Luigi ; Giardino, Marco

In: Geomorphology, 2020, vol. 355, p. 107068

Aosta Valley (Western Alps, Italy) is the region with the largest glacierized area of Italy. Like other high mountain regions, it has shown a significant glacier retreat starting from the end of the ‘Little Ice Age’ that is expected to continue in the future. As a direct consequence of glacier shrinkage, glacier-bed overdeepenings become exposed, offering suitable geomorphological ...

Université de Fribourg

On the imbalance and response time of glaciers in the european alps

Zekollari, Harry ; Huss, Matthias ; Farinotti, Daniel

In: Geophysical Research Letters, 2020, vol. 47, no. 2, p. e2019GL085578

Glaciers in the European Alps rapidly lose mass to adapt to changes in climate conditions. Here, we investigate the relationship and lag between climate forcing and geometric glacier response with a regional glacier evolution model accounting for ice dynamics. The volume loss occurring as a result of the glacier‐climate imbalance increased over the early 21st century, from about 35% in...

Université de Fribourg

Monitoring rock glacier kinematics with satellite synthetic aperture radar

Strozzi, Tazio ; Caduff, Rafael ; Jones, Nina ; Barboux, Chloé ; Delaloye, Reynald ; Bodin, Xavier ; Kääb, Andreas ; Mätzler, Eva ; Schrott, Lothar

In: Remote Sensing, 2020, vol. 12, no. 3, p. 559

Active rock glaciers represent the best visual expression of mountain permafrost that can be mapped and monitored directly using remotely sensed data. Active rock glaciers are bodies that consist of a perennially frozen ice/rock mixture and express a distinct flow-like morphology indicating downslope permafrost creep movement. Annual rates of motion have ranged from a few millimeters to...

Université de Fribourg

A Bayesian ice thickness estimation model for large-scale applications

Werder, Mauro A. ; Huss, Matthias ; Paul, Frank ; Dehecq, Amaury ; Farinotti, Daniel

In: Journal of Glaciology, 2020, vol. 66, no. 255, p. 137–152

Accurate estimations of ice thickness and volume are indispensable for ice flow modelling, hydrological forecasts and sea-level rise projections. We present a new ice thickness estimation model based on a mass-conserving forward model and a Bayesian inversion scheme. The forward model calculates flux in an elevation-band flow-line model, and translates this into ice thickness and surface ice...

Université de Fribourg

Future retreat of Great Aletsch Glacier

Jouvet, Guillaume ; Huss, Matthias

In: Journal of Glaciology, 2019, vol. 65, no. 253, p. 869–872

We model the future evolution of the largest glacier of the European Alps – Great Aletsch Glacier, Switzerland – during the 21st century. For that purpose we use a detailed three-dimensional model, which combines full Stokes ice dynamics and surface mass balance forced with the most recent climate projections (CH2018), as well as with climate data of the last decades. As a result, all...