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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

Permafrost is warming at a global scale

Biskaborn, Boris K. ; Smith, Sharon L. ; Noetzli, Jeannette ; Matthes, Heidrun ; Vieira, Gonçalo ; Streletskiy, Dmitry A. ; Schoeneich, Philippe ; Romanovsky, Vladimir E. ; Lewkowicz, Antoni G. ; Abramov, Andrey ; Allard, Michel ; Boike, Julia ; Cable, William L. ; Christiansen, Hanne H. ; Delaloye, Reynald ; Diekmann, Bernhard ; Drozdov, Dmitry ; Etzelmüller, Bernd ; Grosse, Guido ; Guglielmin, Mauro ; Ingeman-Nielsen, Thomas ; Isaksen, Ketil ; Ishikawa, Mamoru ; Johansson, Margareta ; Johannsson, Halldor ; Joo, Anseok ; Kaverin, Dmitry ; Kholodov, Alexander ; Konstantinov, Pavel ; Kröger, Tim ; Lambiel, Christophe ; Lanckman, Jean-Pierre ; Luo, Dongliang ; Malkova, Galina ; Meiklejohn, Ian ; Moskalenko, Natalia ; Oliva, Marc ; Phillips, Marcia ; Ramos, Miguel ; Sannel, A. Britta K. ; Sergeev, Dmitrii ; Seybold, Cathy ; Skryabin, Pavel ; Vasiliev, Alexander ; Wu, Qingbai ; Yoshikawa, Kenji ; Zheleznyak, Mikhail ; Lantuit, Hugues

In: Nature Communications, 2019, vol. 10, no. 1, p. 264

Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across...

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

Snowpack characteristics on steep frozen rock slopes

Phillips, Marcia ; Haberkorn, Anna ; Rhyner, Hansueli

In: Cold Regions Science and Technology, 2017, vol. 141, no. Supplement C, p. 54–65

Data from 27 snow profiles taken in frozen rock walls at two sites in the Swiss Alps reveal that steep slopes have distinctive snowpack characteristics. Snow pits were dug in 50–65° slopes at elevations between 2900 and 3600masl on north- and south- facing slopes at Gemsstock and Jungfraujoch Sphinx in the winters 2012–2013 and 2013–2014. There were marked contrasts in snow...

Université de Fribourg

New insights on permafrost genesis and conservation in talus slopes based on observations at Flüelapass, Eastern Switzerland

Kenner, Robert ; Phillips, Marcia ; Hauck, Christian ; Hilbich, Christin ; Mulsow, Christian ; Bühler, Yves ; Stoffel, Andreas ; Buchroithner, Manfred

In: Geomorphology, 2017, vol. 290, p. 101–113

The talus slope at Flüelapass was the first mountain permafrost study site in Switzerland in the 1970s and the presence of ice-rich permafrost at the foot of the slope has been investigated in the context of several studies focusing on the role of snow cover distribution. We review previously developed hypotheses and present new ones using various data sources, such as temperature...

Université de Fribourg

Distributed snow and rock temperature modelling in steep rock walls using Alpine3D

Haberkorn, Anna ; Wever, Nander ; Hoelzle, Martin ; Phillips, Marcia ; Kenner, Robert ; Bavay, Mathias ; Lehning, and Michael

In: The Cryosphere, 2017, vol. 11, no. 1, p. 585–607

In this study we modelled the influence of the spatially and temporally heterogeneous snow cover on the surface energy balance and thus on rock temperatures in two rugged, steep rock walls on the Gemsstock ridge in the central Swiss Alps. The heterogeneous snow depth distribution in the rock walls was introduced to the distributed, process-based energy balance model Alpine3D with a...

Université de Fribourg

Thermal and mechanical responses resulting from spatial and temporal snow cover variability in permafrost rock slopes, steintaelli, swiss alps

Draebing, Daniel ; Haberkorn, Anna ; Krautblatter, Michael ; Kenner, Robert ; Phillips, Marcia

In: Permafrost and Periglacial Processes, 2017, vol. 28, no. 1, p. 140–157

The aim of this study is to investigate the influence of snow on permafrost and rock stability at the Steintaelli (Swiss Alps). Snow depth distribution was observed using terrestrial laser scanning and time-lapse photography. The influence of snow on the rock thermal regime was investigated using near-surface rock temperature measurements, seismic refraction tomography and one-dimensional...

Université de Fribourg

Semi-automated calibration method for modelling of mountain permafrost evolution in Switzerland

Marmy, Antoine ; Rajczak, Jan ; Delaloye, Reynald ; Hilbich, Christin ; Hoelzle, Martin ; Kotlarski, Sven ; Lambiel, Christophe ; Noetzli, Jeannette ; Phillips, Marcia ; Salzmann, Nadine ; Staub, Benno ; Hauck, Christian

In: The Cryosphere, 2016, vol. 10, no. 6, p. 2693–2719

Permafrost is a widespread phenomenon in mountainous regions of the world such as the European Alps. Many important topics such as the future evolution of permafrost related to climate change and the detection of permafrost related to potential natural hazards sites are of major concern to our society. Numerical permafrost models are the only tools which allow for the projection of the future...

Université de Fribourg

Seasonally intermittent water flow through deep fractures in an Alpine Rock Ridge: Gemsstock, Central Swiss Alps

Phillips, Marcia ; Haberkorn, , Anna ; Draebing, Daniel ; Krautblatter, Michael ; Rhyner, Hansueli ; Kenner, Robert

In: Cold Regions Science and Technology, 2016, vol. 125, p. 117–127

Geological investigations and seismic refraction tomography reveal a series of 70° steep, parallel and continuous fractures at 2950 m asl within the Gemsstock rock ridge (Central Swiss Alps), at the lower fringe of alpine permafrost. Temperature measurements in a 40 m horizontal borehole through the base of the ridge show that whilst conductive heat transfer dominates within the rock mass,...