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

Numerical reconstructions of the flow and basal conditions of the Rhine glacier, European Central Alps, at the Last Glacial Maximum

Cohen, Denis ; Gillet-Chaulet, Fabien ; Haeberli, Wilfried ; Machguth, Horst ; Fischer, Urs H.

In: The Cryosphere, 2018, vol. 12, no. 8, p. 2515–2544

At the Last Glacial Maximum (LGM), the Rhine glacier in the Swiss Alps covered an area of about 16000km2. As part of an integrative study about the safety of repositories for radioactive waste under ice age conditions in Switzerland, we modeled the Rhine glacier using a thermodynamically coupled three-dimensional, transient Stokes flow and heat transport model down to a horizontal resolution...

Université de Fribourg

Changes in Greenland’s peripheral glaciers linked to the North Atlantic Oscillation

Bjørk?, A. A. ; Aagaard, S. ; Lütt, A. ; Khan, S. A. ; Box, J. E. ; Kjeldsen?, K. K. ; Larsen, N. K. ; Korsgaard?, N. J. ; Cappelen, J. ; Colgan, W. T. ; Machguth, Horst ; Andresen, C. S. ; Peings, Y. ; Kjær, K. H.

In: Nature Climate Change, 2018, vol. 8, no. 1, p. 48–52

Glaciers and ice caps peripheral to the main Greenland Ice Sheet contribute markedly to sea-level rise1,2,3. Their changes and variability, however, have been difficult to quantify on multi-decadal timescales due to an absence of long-term data4. Here, using historical aerial surveys, expedition photographs, spy satellite imagery and new remote-sensing products, we map glacier length...

Université de Fribourg

Re-establishing glacier monitoring in Kyrgyzstan and Uzbekistan, Central Asia

Hoelzle, Martin ; Azisov, Erlan ; Barandun, Martina ; Huss, Matthias ; Farinotti, Daniel ; Gafurov, Abror ; Hagg, Wilfried ; Kenzhebaev, Ruslan ; Kronenberg, Marlene ; Machguth, Horst ; Merkushkin, Alexandr ; Moldobekov, Bolot ; Petrov, Maxim ; Saks, Tomas ; Salzmann, Nadine ; Schöne, Tilo ; Tarasov, Yuri ; Usubaliev, Ryskul ; Vorogushyn, Sergiy ; Yakovlev, Andrey ; Zemp, Michael

In: Geoscientific Instrumentation, Methods and Data Systems, 2017, vol. 6, no. 2, p. 397–418

Glacier mass loss is among the clearest indicators of atmospheric warming. The observation of these changes is one of the major objectives of the international climate monitoring strategy developed by the Global Climate Observing System (GCOS). Long-term glacier mass balance measurements are furthermore the basis for calibrating and validating models simulating future runoff of glacierised...

Université de Fribourg

Modelling glacier-bed overdeepenings and possible future lakes for the glaciers in the Himalaya—Karakoram region

Linsbauer, Andreas ; Frey, H. ; Haeberli, Winfried ; Machguth, Horst ; Azam, M. F. ; Allen, S.

In: Annals of Glaciology, 2016, vol. 57, no. 71, p. 119–130

Surface digital elevation models (DEMs) and slope-related estimates of glacier thickness enable modelling of glacier-bed topographies over large ice-covered areas. Due to the erosive power of glaciers, such bed topographies can contain numerous overdeepenings, which when exposed following glacier retreat may fill with water and form new lakes. In this study, the bed overdeepenings for ~28 000...

Université de Fribourg

Mass balance re-analysis of Findelengletscher, Switzerland; benefits of extensive snow accumulation measurements

Sold, Leo ; Huss, Matthias ; Machguth, Horst ; Joerg, Philip C. ; Leysinger Vieli, Gwendolyn ; Linsbauer, Andreas ; Salzmann, Nadine ; Zemp, Michael ; Hoelzle, Martin

In: Front. Earth Sci. - Cryospheric Sciences, 2016, p. 18

A re-analysis is presented here of a 10 year mass balance series at Findelengletscher, a temperate mountain glacier in Switzerland. Calculating glacier-wide mass balance from the set of glaciological point balance observations using conventional approaches, such as the profile or contour method, resulted in significant deviations from the reference value given by the geodetic mass...

Université de Fribourg

Estimating the volume of glaciers in the Himalayan–Karakoram region using different methods

Frey, H. ; Machguth, Horst ; Huss, Matthias ; Huggel, C. ; Bajracharya, S. ; Bolch, T. ; Kulkarni, A. ; Linsbauer, Andreas ; Salzmann, Nadine ; Stoffel, Markus

In: The Cryosphere, 2014, vol. 8, no. 6, p. 2313–2333

Ice volume estimates are crucial for assessing water reserves stored in glaciers. Due to its large glacier coverage, such estimates are of particular interest for the Himalayan–Karakoram (HK) region. In this study, different existing methodologies are used to estimate the ice reserves: three area–volume relations, one slope-dependent volume estimation method, and two ice-thickness...

Université de Fribourg

A database of worldwide glacier thickness observations

Gärtner-Roer, Isabelle ; Naegeli, K. ; Huss, Matthias ; Knecht, T. ; Machguth, Horst ; Zemp, Michael

In: Global and Planetary Change, 2014, vol. 122, p. 330–344

One of the grand challenges in glacier research is to assess the total ice volume and its global distribution. Over the past few decades the compilation of a world glacier inventory has been well-advanced both in institutional set-up and in spatial coverage. The inventory is restricted to glacier surface observations. However, although thickness has been observed on many glaciers and ice caps...

Université de Fribourg

The Swiss Alpine glaciers' response to the global '2 °C air temperature target'

Salzmann, Nadine ; Machguth, Horst ; Linsbauer, Andreas

In: Environmental Research Letters, 2012, vol. 7, no. 4, p. 044001

While there is general consensus that observed global mean air temperature has increased during the past few decades and will very likely continue to rise in the coming decades, the assessment of the effective impacts of increased global mean air temperature on a specific regional-scale system remains highly challenging. This study takes up the widely discussed concept of limiting global mean...