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Université de Fribourg

Twenty years of European mountain permafrost dynamics—the PACE legacy

Etzelmüller, Bernd ; Guglielmin, Mauro ; Hauck, Christian ; Hilbich, Christin ; Hoelzle, Martin ; Isaksen, Ketil ; Noetzli, Jeanette ; Oliva, Marc ; Ramos, Miguel

In: Environmental Research Letters, 2020, vol. 15, no. 10, p. 104070

This paper reviews and analyses the past 20 years of change and variability of European mountain permafrost in response to climate change based on time series of ground temperatures along a south–north transect of deep boreholes from Sierra Nevada in Spain (37°N) to Svalbard (78°N), established between 1998 and 2000 during the EU-funded PACE (Permafrost and Climate in Europe) project. In...

Université de Fribourg

A full Stokes ice-flow model to assist the interpretation of millennial-scale ice cores at the high-Alpine drilling site Colle Gnifetti, Swiss/Italian Alps

Licciulli, Carlo ; Bohleber, Pascal ; Lier, Josef ; Gagliardini, Olivier ; Hoelzle, Martin ; Eisen, Olaf

In: Journal of Glaciology, 2020, vol. 66, no. 255, p. 35–48

The high-Alpine ice-core drilling site Colle Gnifetti (CG), Monte Rosa, Swiss/Italian Alps, provides climate records over the last millennium and beyond. However, the full exploitation of the oldest part of the existing ice cores requires complementary knowledge of the intricate glacio-meteorological settings, including glacier dynamics. Here, we present new ice-flow modeling studies of CG,...

Université de Fribourg

Distinguishing ice-rich and ice-poor permafrost to map ground temperatures and ground ice occurrence in the Swiss Alps

Kenner, Robert ; Noetzli, Jeannette ; Hoelzle, Martin ; Raetzo, Hugo ; Phillips, Marcia

In: The Cryosphere, 2019, vol. 13, no. 7, p. 1925–1941

Mountain permafrost is invisible, and mapping it is still a challenge. Available permafrost distribution maps often overestimate the permafrost extent and include large permafrost-free areas in their permafrost zonation. In addition, the representation of the lower belt of permafrost consisting of ice-rich features such as rock glaciers or ice-rich talus slopes can be challenging. These...

Université de Fribourg

Change detection of bare-ice albedo in the Swiss Alps

Naegeli, Kathrin ; Huss, Matthias ; Hoelzle, Martin

In: The Cryosphere, 2019, vol. 13, no. 1, p. 397–412

Albedo feedback is an important driver of glacier melt over bare-ice surfaces. Light- absorbing impurities strongly enhance glacier melt rates but their abundance, composition and variations in space and time are subject to considerable uncertainties and ongoing scientific debates. In this study, we assess the temporal evolution of shortwave broadband albedo derived from 15 end-of-summer...

Université de Fribourg

Near-surface ventilation as a key for modeling the thermal regime of coarse blocky rock glaciers

Pruessner, Luisa ; Phillips, Marcia ; Farinotti, Daniel ; Hoelzle, Martin ; Lehning, Michael

In: Permafrost and Periglacial Processes, 2018, vol. 29, no. 3, p. 152–163

In a changing climate, ice‐rich permafrost features such as rock glaciers will experience drastic changes. Modeling the heat transport through the blocky surface layer with its large interstitial pore spaces poses some challenges as various modes of non‐conductive heat transport—advective forms in particular—can occur. Here, we show that the 1D physics‐based model SNOWPACK can be...

Université de Fribourg

Multi-decadal mass balance series of three Kyrgyz glaciers inferred from modelling constrained with repeated snow line observations

Barandun, Martina ; Huss, Matthias ; Usubaliev, Ryskul ; Azisov, Erlan ; Berthier, Etienne ; Kääb, Andreas ; Bolch, Tobias ; Hoelzle, Martin

In: The Cryosphere, 2018, vol. 12, no. 6, p. 1899–1919

Glacier surface mass balance observations in the Tien Shan and Pamir are relatively sparse and often discontinuous. Nevertheless, glaciers are one of the most important components of the high-mountain cryosphere in the region as they strongly influence water availability in the arid, continental and intensely populated downstream areas. This study provides reliable and continuous surface mass...

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

Mass balance observations and reconstruction for Batysh Sook Glacier, Tien Shan, from 2004 to 2016

Kenzhebaev, Ruslan ; Barandun, Martina ; Kronenberg, Marlene ; Chen, Yaning ; Usubaliev, Ryskul ; Hoelzle, Martin

In: Cold Regions Science and Technology, 2017, vol. 135, p. 76-89

In this study we present an analysis of measured annual mass balances for the period 2011 to 2016 and a reconstruction of seasonal mass balances from 2004 to 2010 for Batysh Sook Glacier located in the Kyrgyz Tien Shan. Conventional methods and a model-based extrapolation of the point measurements were used to obtain glacier- wide mass balances and to analyze glaciological measurements....