Articles | Volume 17, issue 12
https://doi.org/10.5194/tc-17-5477-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-17-5477-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Dec 2023
Research article |
| 22 Dec 2023
| 22 Dec 2023
Rapid warming and degradation of mountain permafrost in Norway and Iceland
Bernd Etzelmüller
CORRESPONDING AUTHOR
Department of Geosciences, University of Oslo, 1047 Blindern, Oslo, Norway
Ketil Isaksen
Meteorological Institute of Norway, Oslo, Norway
Justyna Czekirda
Department of Geosciences, University of Oslo, 1047 Blindern, Oslo, Norway
Sebastian Westermann
Department of Geosciences, University of Oslo, 1047 Blindern, Oslo, Norway
Christin Hilbich
Department of Geosciences, University of Fribourg, Fribourg, Switzerland
Christian Hauck
Department of Geosciences, University of Fribourg, Fribourg, Switzerland
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Anatoly O. Sinitsyn, Sara Bazin, Rasmus Benestad, Bernd Etzelmüller, Ketil Isaksen, Hanne Kvitsand, Julia Lutz, Andrea L. Popp, Lena Rubensdotter, and Sebastian Westermann
EGUsphere, https://doi.org/10.5194/egusphere-2023-2950, https://doi.org/10.5194/egusphere-2023-2950, 2023
Preprint archived
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This study looked at under the ground on Svalbard, an archipelago close to the North Pole. We found something very surprising – there is water under the all year around frozen soil. This was not known before. This water could be used for drinking if we manage it carefully. This is important because getting clean drinking water is very difficult in Svalbard, and other Arctic places. Also, because the climate is getting warmer, there might be even more water underground in the future.
Justyna Czekirda, Bernd Etzelmüller, Sebastian Westermann, Ketil Isaksen, and Florence Magnin
The Cryosphere, 17, 2725–2754, https://doi.org/10.5194/tc-17-2725-2023, https://doi.org/10.5194/tc-17-2725-2023, 2023
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We assess spatio-temporal permafrost variations in selected rock walls in Norway over the last 120 years. Ground temperature is modelled using the two-dimensional ground heat flux model CryoGrid 2D along nine profiles. Permafrost probably occurs at most sites. All simulations show increasing ground temperature from the 1980s. Our simulations show that rock wall permafrost with a temperature of −1 °C at 20 m depth could thaw at this depth within 50 years.
Sebastian Westermann, Thomas Ingeman-Nielsen, Johanna Scheer, Kristoffer Aalstad, Juditha Aga, Nitin Chaudhary, Bernd Etzelmüller, Simon Filhol, Andreas Kääb, Cas Renette, Louise Steffensen Schmidt, Thomas Vikhamar Schuler, Robin B. Zweigel, Léo Martin, Sarah Morard, Matan Ben-Asher, Michael Angelopoulos, Julia Boike, Brian Groenke, Frederieke Miesner, Jan Nitzbon, Paul Overduin, Simone M. Stuenzi, and Moritz Langer
Geosci. Model Dev., 16, 2607–2647, https://doi.org/10.5194/gmd-16-2607-2023, https://doi.org/10.5194/gmd-16-2607-2023, 2023
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The CryoGrid community model is a new tool for simulating ground temperatures and the water and ice balance in cold regions. It is a modular design, which makes it possible to test different schemes to simulate, for example, permafrost ground in an efficient way. The model contains tools to simulate frozen and unfrozen ground, snow, glaciers, and other massive ice bodies, as well as water bodies.
Cas Renette, Kristoffer Aalstad, Juditha Aga, Robin Benjamin Zweigel, Bernd Etzelmüller, Karianne Staalesen Lilleøren, Ketil Isaksen, and Sebastian Westermann
Earth Surf. Dynam., 11, 33–50, https://doi.org/10.5194/esurf-11-33-2023, https://doi.org/10.5194/esurf-11-33-2023, 2023
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One of the reasons for lower ground temperatures in coarse, blocky terrain is a low or varying soil moisture content, which most permafrost modelling studies did not take into account. We used the CryoGrid community model to successfully simulate this effect and found markedly lower temperatures in well-drained, blocky deposits compared to other set-ups. The inclusion of this drainage effect is another step towards a better model representation of blocky mountain terrain in permafrost regions.
Karianne S. Lilleøren, Bernd Etzelmüller, Line Rouyet, Trond Eiken, Gaute Slinde, and Christin Hilbich
Earth Surf. Dynam., 10, 975–996, https://doi.org/10.5194/esurf-10-975-2022, https://doi.org/10.5194/esurf-10-975-2022, 2022
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In northern Norway we have observed several rock glaciers at sea level. Rock glaciers are landforms that only form under the influence of permafrost, which is frozen ground. Our investigations show that the rock glaciers are probably not active under the current climate but most likely were active in the recent past. This shows how the Arctic now changes due to climate changes and also how similar areas in currently colder climates will change in the future.
Aldo Bertone, Chloé Barboux, Xavier Bodin, Tobias Bolch, Francesco Brardinoni, Rafael Caduff, Hanne H. Christiansen, Margaret M. Darrow, Reynald Delaloye, Bernd Etzelmüller, Ole Humlum, Christophe Lambiel, Karianne S. Lilleøren, Volkmar Mair, Gabriel Pellegrinon, Line Rouyet, Lucas Ruiz, and Tazio Strozzi
The Cryosphere, 16, 2769–2792, https://doi.org/10.5194/tc-16-2769-2022, https://doi.org/10.5194/tc-16-2769-2022, 2022
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We present the guidelines developed by the IPA Action Group and within the ESA Permafrost CCI project to include InSAR-based kinematic information in rock glacier inventories. Nine operators applied these guidelines to 11 regions worldwide; more than 3600 rock glaciers are classified according to their kinematics. We test and demonstrate the feasibility of applying common rules to produce homogeneous kinematic inventories at global scale, useful for hydrological and climate change purposes.
Noah D. Smith, Eleanor J. Burke, Kjetil Schanke Aas, Inge H. J. Althuizen, Julia Boike, Casper Tai Christiansen, Bernd Etzelmüller, Thomas Friborg, Hanna Lee, Heather Rumbold, Rachael H. Turton, Sebastian Westermann, and Sarah E. Chadburn
Geosci. Model Dev., 15, 3603–3639, https://doi.org/10.5194/gmd-15-3603-2022, https://doi.org/10.5194/gmd-15-3603-2022, 2022
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The Arctic has large areas of small mounds that are caused by ice lifting up the soil. Snow blown by wind gathers in hollows next to these mounds, insulating them in winter. The hollows tend to be wetter, and thus the soil absorbs more heat in summer. The warm wet soil in the hollows decomposes, releasing methane. We have made a model of this, and we have tested how it behaves and whether it looks like sites in Scandinavia and Siberia. Sometimes we get more methane than a model without mounds.
Bernd Etzelmüller, Justyna Czekirda, Florence Magnin, Pierre-Allain Duvillard, Ludovic Ravanel, Emanuelle Malet, Andreas Aspaas, Lene Kristensen, Ingrid Skrede, Gudrun D. Majala, Benjamin Jacobs, Johannes Leinauer, Christian Hauck, Christin Hilbich, Martina Böhme, Reginald Hermanns, Harald Ø. Eriksen, Tom Rune Lauknes, Michael Krautblatter, and Sebastian Westermann
Earth Surf. Dynam., 10, 97–129, https://doi.org/10.5194/esurf-10-97-2022, https://doi.org/10.5194/esurf-10-97-2022, 2022
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This paper is a multi-authored study documenting the possible existence of permafrost in permanently monitored rockslides in Norway for the first time by combining a multitude of field data, including geophysical surveys in rock walls. The paper discusses the possible role of thermal regime and rockslide movement, and it evaluates the possible impact of atmospheric warming on rockslide dynamics in Norwegian mountains.
Léo C. P. Martin, Jan Nitzbon, Johanna Scheer, Kjetil S. Aas, Trond Eiken, Moritz Langer, Simon Filhol, Bernd Etzelmüller, and Sebastian Westermann
The Cryosphere, 15, 3423–3442, https://doi.org/10.5194/tc-15-3423-2021, https://doi.org/10.5194/tc-15-3423-2021, 2021
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It is important to understand how permafrost landscapes respond to climate changes because their thaw can contribute to global warming. We investigate how a common permafrost morphology degrades using both field observations of the surface elevation and numerical modeling. We show that numerical models accounting for topographic changes related to permafrost degradation can reproduce the observed changes in nature and help us understand how parameters such as snow influence this phenomenon.
Juditha Undine Schmidt, Bernd Etzelmüller, Thomas Vikhamar Schuler, Florence Magnin, Julia Boike, Moritz Langer, and Sebastian Westermann
The Cryosphere, 15, 2491–2509, https://doi.org/10.5194/tc-15-2491-2021, https://doi.org/10.5194/tc-15-2491-2021, 2021
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This study presents rock surface temperatures (RSTs) of steep high-Arctic rock walls on Svalbard from 2016 to 2020. The field data show that coastal cliffs are characterized by warmer RSTs than inland locations during winter seasons. By running model simulations, we analyze factors leading to that effect, calculate the surface energy balance and simulate different future scenarios. Both field data and model results can contribute to a further understanding of RST in high-Arctic rock walls.
Florence Magnin, Bernd Etzelmüller, Sebastian Westermann, Ketil Isaksen, Paula Hilger, and Reginald L. Hermanns
Earth Surf. Dynam., 7, 1019–1040, https://doi.org/10.5194/esurf-7-1019-2019, https://doi.org/10.5194/esurf-7-1019-2019, 2019
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This study proposes the first permafrost (i.e. ground with temperature permanently < 0 °C) map covering the steep rock slopes of Norway. It was created by using rock temperature data collected at the near surface of 25 rock walls spread across the country between 2010 and 2018. The map shows that permafrost mostly exists above 1300–1400 m a.s.l. in southern Norway and close to sea level in northern Norway. The results have strong potential for the study of rock wall sliding and failure.
Sebastian Westermann, Maria Peter, Moritz Langer, Georg Schwamborn, Lutz Schirrmeister, Bernd Etzelmüller, and Julia Boike
The Cryosphere, 11, 1441–1463, https://doi.org/10.5194/tc-11-1441-2017, https://doi.org/10.5194/tc-11-1441-2017, 2017
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We demonstrate a remote-sensing-based scheme estimating the evolution of ground temperature and active layer thickness by means of a ground thermal model. A comparison to in situ observations from the Lena River delta in Siberia indicates that the model is generally capable of reproducing the annual temperature regime and seasonal thawing of the ground. The approach could hence be a first step towards remote detection of ground thermal conditions in permafrost areas.
Luc Girod, Christopher Nuth, Andreas Kääb, Bernd Etzelmüller, and Jack Kohler
The Cryosphere, 11, 827–840, https://doi.org/10.5194/tc-11-827-2017, https://doi.org/10.5194/tc-11-827-2017, 2017
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While gathering data on a changing environment is often a costly and complicated endeavour, it is also the backbone of all research. What if one could measure elevation change by just strapping a camera and a hiking GPS under an helicopter or a small airplane used for transportation and gather data on the ground bellow the flight path? In this article, we present a way to do exactly that and show an example survey where it helped compute the volume of ice lost by a glacier in Svalbard.
Amund F. Borge, Sebastian Westermann, Ingvild Solheim, and Bernd Etzelmüller
The Cryosphere, 11, 1–16, https://doi.org/10.5194/tc-11-1-2017, https://doi.org/10.5194/tc-11-1-2017, 2017
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Palsas and peat plateaus are permafrost landforms in subarctic mires which constitute sensitive ecosystems with strong significance for vegetation, wildlife, hydrology and carbon cycle. We have systematically mapped the occurrence of palsas and peat plateaus in northern Norway by interpretation of aerial images from the 1950s until today. The results show that about half of the area of palsas and peat plateaus has disappeared due to lateral erosion and melting of ground ice in the last 50 years.
Kjersti Gisnås, Sebastian Westermann, Thomas Vikhamar Schuler, Kjetil Melvold, and Bernd Etzelmüller
The Cryosphere, 10, 1201–1215, https://doi.org/10.5194/tc-10-1201-2016, https://doi.org/10.5194/tc-10-1201-2016, 2016
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In wind exposed areas snow redistribution results in large spatial variability in ground temperatures. In these areas, the ground temperature of a grid cell must be determined based on the distribution, and not the average, of snow depths. We employ distribution functions of snow in a regional permafrost model, showing highly improved representation of ground temperatures. By including snow distributions, we find the permafrost area to be nearly twice as large as what is modelled without.
S. Westermann, M. Langer, J. Boike, M. Heikenfeld, M. Peter, B. Etzelmüller, and G. Krinner
Geosci. Model Dev., 9, 523–546, https://doi.org/10.5194/gmd-9-523-2016, https://doi.org/10.5194/gmd-9-523-2016, 2016
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Thawing of permafrost is governed by a complex interplay of different processes, of which only conductive heat transfer is taken into account in most model studies. We present a new land-surface scheme designed for permafrost applications, CryoGrid 3, which constitutes a flexible platform to explore new parameterizations for a range of permafrost processes.
S. Westermann, T. I. Østby, K. Gisnås, T. V. Schuler, and B. Etzelmüller
The Cryosphere, 9, 1303–1319, https://doi.org/10.5194/tc-9-1303-2015, https://doi.org/10.5194/tc-9-1303-2015, 2015
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We use remotely sensed land surface temperature and land cover in conjunction with air temperature and snowfall from a reanalysis product as input for a simple permafrost model. The scheme is applied to the permafrost regions bordering the North Atlantic. A comparison with ground temperatures in boreholes suggests a modeling accuracy of 2 to 2.5 °C.
K. Gisnås, S. Westermann, T. V. Schuler, T. Litherland, K. Isaksen, J. Boike, and B. Etzelmüller
The Cryosphere, 8, 2063–2074, https://doi.org/10.5194/tc-8-2063-2014, https://doi.org/10.5194/tc-8-2063-2014, 2014
S. Westermann, T. V. Schuler, K. Gisnås, and B. Etzelmüller
The Cryosphere, 7, 719–739, https://doi.org/10.5194/tc-7-719-2013, https://doi.org/10.5194/tc-7-719-2013, 2013
Sigrid Trier Kjær, Sebastian Westermann, Nora Nedkvitne, and Peter Dörsch
Biogeosciences, 21, 4723–4737, https://doi.org/10.5194/bg-21-4723-2024, https://doi.org/10.5194/bg-21-4723-2024, 2024
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Permafrost peatlands are thawing due to climate change, releasing large quantities of carbon that degrades upon thawing and is released as CO2, CH4 or dissolved organic carbon (DOC). We incubated thawed Norwegian permafrost peat plateaus and thermokarst pond sediment found next to permafrost for up to 350 d to measure carbon loss. CO2 production was initially the highest, whereas CH4 production increased over time. The largest carbon loss was measured at the top of the peat plateau core as DOC.
Tamara Mathys, Muslim Azimshoev, Zhoodarbeshim Bektursunov, Christian Hauck, Christin Hilbich, Murataly Duishonakunov, Abdulhamid Kayumov, Nikolay Kassatkin, Vassily Kapitsa, Leo C. P. Martin, Coline Mollaret, Hofiz Navruzshoev, Eric Pohl, Tomas Saks, Intizor Silmonov, Timur Musaev, Ryskul Usubaliev, and Martin Hoelzle
EGUsphere, https://doi.org/10.5194/egusphere-2024-2795, https://doi.org/10.5194/egusphere-2024-2795, 2024
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This study provides a comprehensive geophysical dataset on permafrost in the data-scarce Tien Shan and Pamir mountain regions of Central Asia. It also introduces a novel modeling method to quantify ground ice content across different landforms. The findings indicate that this approach is well-suited for characterizing ice-rich permafrost, which is crucial for evaluating future water availability and assessing risks associated with thawing permafrost.
Cassandra E.M. Koenig, Christin Hilbich, Christian Hauck, Lukas U. Arenson, and Pablo Wainstein
EGUsphere, https://doi.org/10.5194/egusphere-2024-2244, https://doi.org/10.5194/egusphere-2024-2244, 2024
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This study presents an analysis of ground temperature data from 53 high-altitude boreholes in permafrost regions of the Central Andes. Results show that thermal characteristics of the region align with other mountain permafrost areas, while also showing unique features. The dataset could improve permafrost models and monitoring efforts, and inform mitigation strategies. The study highlights a notable collaboration between industry, academia, and regulators for advancing climate change research.
Juditha Aga, Livia Piermattei, Luc Girod, Kristoffer Aalstad, Trond Eiken, Andreas Kääb, and Sebastian Westermann
Earth Surf. Dynam., 12, 1049–1070, https://doi.org/10.5194/esurf-12-1049-2024, https://doi.org/10.5194/esurf-12-1049-2024, 2024
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Coastal rock cliffs on Svalbard are considered to be fairly stable; however, long-term trends in coastal-retreat rates remain unknown. This study examines changes in the coastline position along Brøggerhalvøya, Svalbard, using aerial images from 1970, 1990, 2010, and 2021. Our analysis shows that coastal-retreat rates accelerate during the period 2010–2021, which coincides with increasing storminess and retreating sea ice.
Mohammad Farzamian, Teddi Herring, Gonçalo Vieira, Miguel Angel de Pablo, Borhan Yaghoobi Tabar, and Christian Hauck
The Cryosphere, 18, 4197–4213, https://doi.org/10.5194/tc-18-4197-2024, https://doi.org/10.5194/tc-18-4197-2024, 2024
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An automated electrical resistivity tomography (A-ERT) system was developed and deployed in Antarctica to monitor permafrost and active-layer dynamics. The A-ERT, coupled with an efficient processing workflow, demonstrated its capability to monitor real-time thaw depth progression, detect seasonal and surficial freezing–thawing events, and assess permafrost stability. Our study showcased the potential of A-ERT to contribute to global permafrost monitoring networks.
Theresa Maierhofer, Adrian Flores Orozco, Nathalie Roser, Jonas K. Limbrock, Christin Hilbich, Clemens Moser, Andreas Kemna, Elisabetta Drigo, Umberto Morra di Cella, and Christian Hauck
The Cryosphere, 18, 3383–3414, https://doi.org/10.5194/tc-18-3383-2024, https://doi.org/10.5194/tc-18-3383-2024, 2024
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In this study, we apply an electrical method in a high-mountain permafrost terrain in the Italian Alps, where long-term borehole temperature data are available for validation. In particular, we investigate the frequency dependence of the electrical properties for seasonal and annual variations along a 3-year monitoring period. We demonstrate that our method is capable of resolving temporal changes in the thermal state and the ice / water ratio associated with seasonal freeze–thaw processes.
Robin B. Zweigel, Avirmed Dashtseren, Khurelbaatar Temuujin, Anarmaa Sharkhuu, Clare Webster, Hanna Lee, and Sebastian Westermann
EGUsphere, https://doi.org/10.5194/egusphere-2024-1790, https://doi.org/10.5194/egusphere-2024-1790, 2024
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Intense grazing at grassland sites removes vegetation, reduces the snow cover, and inhibits litter layers from forming. Grazed sites generally have a larger annual ground surface temperature amplitude than ungrazed sites, but the net effect depends on effects in the transitional seasons. Our results also suggest that seasonal use of pastures can reduce ground temperatures, which can be a strategy to protect currently degrading grassland permafrost.
Clemens Moser, Umberto Morra di Cella, Christian Hauck, and Adrián Flores Orozco
EGUsphere, https://doi.org/10.5194/egusphere-2024-1444, https://doi.org/10.5194/egusphere-2024-1444, 2024
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We quantify hydrogeological properties in an active rock glacier by using electrical conductivity and induced polarization in an imaging framework and we used geophysical monitoring to track tracer test injections. The water content is spatially variable, and the water can move rapidly with a velocity in the range of cm/s through the active layer of the rock glacier. Hydrogeological parameters were linked to kinematic data to investigate the role of water content on rock glacier movement.
Marco Mazzolini, Kristoffer Aalstad, Esteban Alonso-González, Sebastian Westermann, and Désirée Treichler
EGUsphere, https://doi.org/10.5194/egusphere-2024-1404, https://doi.org/10.5194/egusphere-2024-1404, 2024
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In this work, we use the satellite laser altimeter ICESat-2 to retrieve snow depth in areas where snow amounts are still poorly estimated despite the high societal importance. We explore how to update snow models with these observations through algorithms that spatially propagate the information beyond the narrow satellite profiles. The positive results show the potential of this approach for improving snow simulations, both in terms of average snow depth and spatial distribution.
Julie Wee, Sebastián Vivero, Tamara Mathys, Coline Mollaret, Christian Hauck, Christophe Lambiel, Jan Beutel, and Wilfried Haeberli
EGUsphere, https://doi.org/10.5194/egusphere-2024-1283, https://doi.org/10.5194/egusphere-2024-1283, 2024
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This study highlights the importance of a multi-method and multidisciplinary approach to better understand the influence of the internal structure of the Gruben glacier forefield-connected rock glacier and adjacent debris-covered glacier on their driving thermo-mechanical processes and associated surface dynamics. We were able to discriminate glacial from periglacial processes as their spatio-temporal patterns of surface dynamics and geophysical signatures are (mostly) different.
Wilfried Haeberli, Lukas U. Arenson, Julie Wee, Christian Hauck, and Nico Mölg
The Cryosphere, 18, 1669–1683, https://doi.org/10.5194/tc-18-1669-2024, https://doi.org/10.5194/tc-18-1669-2024, 2024
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Rock glaciers in ice-rich permafrost can be discriminated from debris-covered glaciers. The key physical phenomenon relates to the tight mechanical coupling between the moving frozen body at depth and the surface layer of debris in the case of rock glaciers, as opposed to the virtually inexistent coupling in the case of surface ice with a debris cover. Contact zones of surface ice with subsurface ice in permafrost constitute diffuse landforms beyond either–or-type landform classification.
Moritz Langer, Jan Nitzbon, Brian Groenke, Lisa-Marie Assmann, Thomas Schneider von Deimling, Simone Maria Stuenzi, and Sebastian Westermann
The Cryosphere, 18, 363–385, https://doi.org/10.5194/tc-18-363-2024, https://doi.org/10.5194/tc-18-363-2024, 2024
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Using a model that can simulate the evolution of Arctic permafrost over centuries to millennia, we find that post-industrialization permafrost warming has three "hotspots" in NE Canada, N Alaska, and W Siberia. The extent of near-surface permafrost has decreased substantially since 1850, with the largest area losses occurring in the last 50 years. The simulations also show that volcanic eruptions have in some cases counteracted the loss of near-surface permafrost for a few decades.
Esteban Alonso-González, Kristoffer Aalstad, Norbert Pirk, Marco Mazzolini, Désirée Treichler, Paul Leclercq, Sebastian Westermann, Juan Ignacio López-Moreno, and Simon Gascoin
Hydrol. Earth Syst. Sci., 27, 4637–4659, https://doi.org/10.5194/hess-27-4637-2023, https://doi.org/10.5194/hess-27-4637-2023, 2023
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Here we explore how to improve hyper-resolution (5 m) distributed snowpack simulations using sparse observations, which do not provide information from all the areas of the simulation domain. We propose a new way of propagating information throughout the simulations adapted to the hyper-resolution, which could also be used to improve simulations of other nature. The method has been implemented in an open-source data assimilation tool that is readily accessible to everyone.
Anatoly O. Sinitsyn, Sara Bazin, Rasmus Benestad, Bernd Etzelmüller, Ketil Isaksen, Hanne Kvitsand, Julia Lutz, Andrea L. Popp, Lena Rubensdotter, and Sebastian Westermann
EGUsphere, https://doi.org/10.5194/egusphere-2023-2950, https://doi.org/10.5194/egusphere-2023-2950, 2023
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This study looked at under the ground on Svalbard, an archipelago close to the North Pole. We found something very surprising – there is water under the all year around frozen soil. This was not known before. This water could be used for drinking if we manage it carefully. This is important because getting clean drinking water is very difficult in Svalbard, and other Arctic places. Also, because the climate is getting warmer, there might be even more water underground in the future.
Léo C. P. Martin, Sebastian Westermann, Michele Magni, Fanny Brun, Joel Fiddes, Yanbin Lei, Philip Kraaijenbrink, Tamara Mathys, Moritz Langer, Simon Allen, and Walter W. Immerzeel
Hydrol. Earth Syst. Sci., 27, 4409–4436, https://doi.org/10.5194/hess-27-4409-2023, https://doi.org/10.5194/hess-27-4409-2023, 2023
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Across the Tibetan Plateau, many large lakes have been changing level during the last decades as a response to climate change. In high-mountain environments, water fluxes from the land to the lakes are linked to the ground temperature of the land and to the energy fluxes between the ground and the atmosphere, which are modified by climate change. With a numerical model, we test how these water and energy fluxes have changed over the last decades and how they influence the lake level variations.
Juditha Aga, Julia Boike, Moritz Langer, Thomas Ingeman-Nielsen, and Sebastian Westermann
The Cryosphere, 17, 4179–4206, https://doi.org/10.5194/tc-17-4179-2023, https://doi.org/10.5194/tc-17-4179-2023, 2023
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This study presents a new model scheme for simulating ice segregation and thaw consolidation in permafrost environments, depending on ground properties and climatic forcing. It is embedded in the CryoGrid community model, a land surface model for the terrestrial cryosphere. We describe the model physics and functionalities, followed by a model validation and a sensitivity study of controlling factors.
Matan Ben-Asher, Florence Magnin, Sebastian Westermann, Josué Bock, Emmanuel Malet, Johan Berthet, Ludovic Ravanel, and Philip Deline
Earth Surf. Dynam., 11, 899–915, https://doi.org/10.5194/esurf-11-899-2023, https://doi.org/10.5194/esurf-11-899-2023, 2023
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Quantitative knowledge of water availability on high mountain rock slopes is very limited. We use a numerical model and field measurements to estimate the water balance at a steep rock wall site. We show that snowmelt is the main source of water at elevations >3600 m and that snowpack hydrology and sublimation are key factors. The new information presented here can be used to improve the understanding of thermal, hydrogeological, and mechanical processes on steep mountain rock slopes.
Brian Groenke, Moritz Langer, Jan Nitzbon, Sebastian Westermann, Guillermo Gallego, and Julia Boike
The Cryosphere, 17, 3505–3533, https://doi.org/10.5194/tc-17-3505-2023, https://doi.org/10.5194/tc-17-3505-2023, 2023
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It is now well known from long-term temperature measurements that Arctic permafrost, i.e., ground that remains continuously frozen for at least 2 years, is warming in response to climate change. Temperature, however, only tells half of the story. In this study, we use computer modeling to better understand how the thawing and freezing of water in the ground affects the way permafrost responds to climate change and what temperature trends can and cannot tell us about how permafrost is changing.
Louise Steffensen Schmidt, Thomas Vikhamar Schuler, Erin Emily Thomas, and Sebastian Westermann
The Cryosphere, 17, 2941–2963, https://doi.org/10.5194/tc-17-2941-2023, https://doi.org/10.5194/tc-17-2941-2023, 2023
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Here, we present high-resolution simulations of glacier mass balance (the gain and loss of ice over a year) and runoff on Svalbard from 1991–2022, one of the fastest warming regions in the Arctic. The simulations are created using the CryoGrid community model. We find a small overall loss of mass over the simulation period of −0.08 m yr−1 but with no statistically significant trend. The average runoff was found to be 41 Gt yr−1, with a significant increasing trend of 6.3 Gt per decade.
Johannes Buckel, Jan Mudler, Rainer Gardeweg, Christian Hauck, Christin Hilbich, Regula Frauenfelder, Christof Kneisel, Sebastian Buchelt, Jan Henrik Blöthe, Andreas Hördt, and Matthias Bücker
The Cryosphere, 17, 2919–2940, https://doi.org/10.5194/tc-17-2919-2023, https://doi.org/10.5194/tc-17-2919-2023, 2023
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This study reveals permafrost degradation by repeating old geophysical measurements at three Alpine sites. The compared data indicate that ice-poor permafrost is highly affected by temperature warming. The melting of ice-rich permafrost could not be identified. However, complex geomorphic processes are responsible for this rather than external temperature change. We suspect permafrost degradation here as well. In addition, we introduce a new current injection method for data acquisition.
Justyna Czekirda, Bernd Etzelmüller, Sebastian Westermann, Ketil Isaksen, and Florence Magnin
The Cryosphere, 17, 2725–2754, https://doi.org/10.5194/tc-17-2725-2023, https://doi.org/10.5194/tc-17-2725-2023, 2023
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We assess spatio-temporal permafrost variations in selected rock walls in Norway over the last 120 years. Ground temperature is modelled using the two-dimensional ground heat flux model CryoGrid 2D along nine profiles. Permafrost probably occurs at most sites. All simulations show increasing ground temperature from the 1980s. Our simulations show that rock wall permafrost with a temperature of −1 °C at 20 m depth could thaw at this depth within 50 years.
Norbert Pirk, Kristoffer Aalstad, Yeliz A. Yilmaz, Astrid Vatne, Andrea L. Popp, Peter Horvath, Anders Bryn, Ane Victoria Vollsnes, Sebastian Westermann, Terje Koren Berntsen, Frode Stordal, and Lena Merete Tallaksen
Biogeosciences, 20, 2031–2047, https://doi.org/10.5194/bg-20-2031-2023, https://doi.org/10.5194/bg-20-2031-2023, 2023
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We measured the land–atmosphere exchange of CO2 and water vapor in alpine Norway over 3 years. The extremely snow-rich conditions in 2020 reduced the total annual evapotranspiration to 50 % and reduced the growing-season carbon assimilation to turn the ecosystem from a moderate annual carbon sink to an even stronger source. Our analysis suggests that snow cover anomalies are driving the most consequential short-term responses in this ecosystem’s functioning.
Sebastian Westermann, Thomas Ingeman-Nielsen, Johanna Scheer, Kristoffer Aalstad, Juditha Aga, Nitin Chaudhary, Bernd Etzelmüller, Simon Filhol, Andreas Kääb, Cas Renette, Louise Steffensen Schmidt, Thomas Vikhamar Schuler, Robin B. Zweigel, Léo Martin, Sarah Morard, Matan Ben-Asher, Michael Angelopoulos, Julia Boike, Brian Groenke, Frederieke Miesner, Jan Nitzbon, Paul Overduin, Simone M. Stuenzi, and Moritz Langer
Geosci. Model Dev., 16, 2607–2647, https://doi.org/10.5194/gmd-16-2607-2023, https://doi.org/10.5194/gmd-16-2607-2023, 2023
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The CryoGrid community model is a new tool for simulating ground temperatures and the water and ice balance in cold regions. It is a modular design, which makes it possible to test different schemes to simulate, for example, permafrost ground in an efficient way. The model contains tools to simulate frozen and unfrozen ground, snow, glaciers, and other massive ice bodies, as well as water bodies.
Adrian Wicki, Peter Lehmann, Christian Hauck, and Manfred Stähli
Nat. Hazards Earth Syst. Sci., 23, 1059–1077, https://doi.org/10.5194/nhess-23-1059-2023, https://doi.org/10.5194/nhess-23-1059-2023, 2023
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Soil wetness measurements are used for shallow landslide prediction; however, existing sites are often located in flat terrain. Here, we assessed the ability of monitoring sites at flat locations to detect critically saturated conditions compared to if they were situated at a landslide-prone location. We found that differences exist but that both sites could equally well distinguish critical from non-critical conditions for shallow landslide triggering if relative changes are considered.
Cas Renette, Kristoffer Aalstad, Juditha Aga, Robin Benjamin Zweigel, Bernd Etzelmüller, Karianne Staalesen Lilleøren, Ketil Isaksen, and Sebastian Westermann
Earth Surf. Dynam., 11, 33–50, https://doi.org/10.5194/esurf-11-33-2023, https://doi.org/10.5194/esurf-11-33-2023, 2023
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One of the reasons for lower ground temperatures in coarse, blocky terrain is a low or varying soil moisture content, which most permafrost modelling studies did not take into account. We used the CryoGrid community model to successfully simulate this effect and found markedly lower temperatures in well-drained, blocky deposits compared to other set-ups. The inclusion of this drainage effect is another step towards a better model representation of blocky mountain terrain in permafrost regions.
Norbert Pirk, Kristoffer Aalstad, Sebastian Westermann, Astrid Vatne, Alouette van Hove, Lena Merete Tallaksen, Massimo Cassiani, and Gabriel Katul
Atmos. Meas. Tech., 15, 7293–7314, https://doi.org/10.5194/amt-15-7293-2022, https://doi.org/10.5194/amt-15-7293-2022, 2022
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In this study, we show how sparse and noisy drone measurements can be combined with an ensemble of turbulence-resolving wind simulations to estimate uncertainty-aware surface energy exchange. We demonstrate the feasibility of this drone data assimilation framework in a series of synthetic and real-world experiments. This new framework can, in future, be applied to estimate energy and gas exchange in heterogeneous landscapes more representatively than conventional methods.
Karianne S. Lilleøren, Bernd Etzelmüller, Line Rouyet, Trond Eiken, Gaute Slinde, and Christin Hilbich
Earth Surf. Dynam., 10, 975–996, https://doi.org/10.5194/esurf-10-975-2022, https://doi.org/10.5194/esurf-10-975-2022, 2022
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In northern Norway we have observed several rock glaciers at sea level. Rock glaciers are landforms that only form under the influence of permafrost, which is frozen ground. Our investigations show that the rock glaciers are probably not active under the current climate but most likely were active in the recent past. This shows how the Arctic now changes due to climate changes and also how similar areas in currently colder climates will change in the future.
Juri Palmtag, Jaroslav Obu, Peter Kuhry, Andreas Richter, Matthias B. Siewert, Niels Weiss, Sebastian Westermann, and Gustaf Hugelius
Earth Syst. Sci. Data, 14, 4095–4110, https://doi.org/10.5194/essd-14-4095-2022, https://doi.org/10.5194/essd-14-4095-2022, 2022
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The northern permafrost region covers 22 % of the Northern Hemisphere and holds almost twice as much carbon as the atmosphere. This paper presents data from 651 soil pedons encompassing more than 6500 samples from 16 different study areas across the northern permafrost region. We use this dataset together with ESA's global land cover dataset to estimate soil organic carbon and total nitrogen storage up to 300 cm soil depth, with estimated values of 813 Pg for carbon and 55 Pg for nitrogen.
Aldo Bertone, Chloé Barboux, Xavier Bodin, Tobias Bolch, Francesco Brardinoni, Rafael Caduff, Hanne H. Christiansen, Margaret M. Darrow, Reynald Delaloye, Bernd Etzelmüller, Ole Humlum, Christophe Lambiel, Karianne S. Lilleøren, Volkmar Mair, Gabriel Pellegrinon, Line Rouyet, Lucas Ruiz, and Tazio Strozzi
The Cryosphere, 16, 2769–2792, https://doi.org/10.5194/tc-16-2769-2022, https://doi.org/10.5194/tc-16-2769-2022, 2022
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We present the guidelines developed by the IPA Action Group and within the ESA Permafrost CCI project to include InSAR-based kinematic information in rock glacier inventories. Nine operators applied these guidelines to 11 regions worldwide; more than 3600 rock glaciers are classified according to their kinematics. We test and demonstrate the feasibility of applying common rules to produce homogeneous kinematic inventories at global scale, useful for hydrological and climate change purposes.
Tamara Mathys, Christin Hilbich, Lukas U. Arenson, Pablo A. Wainstein, and Christian Hauck
The Cryosphere, 16, 2595–2615, https://doi.org/10.5194/tc-16-2595-2022, https://doi.org/10.5194/tc-16-2595-2022, 2022
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With ongoing climate change, there is a pressing need to understand how much water is stored as ground ice in permafrost. Still, field-based data on permafrost in the Andes are scarce, resulting in large uncertainties regarding ground ice volumes and their hydrological role. We introduce an upscaling methodology of geophysical-based ground ice quantifications at the catchment scale. Our results indicate that substantial ground ice volumes may also be present in areas without rock glaciers.
Theresa Maierhofer, Christian Hauck, Christin Hilbich, Andreas Kemna, and Adrián Flores-Orozco
The Cryosphere, 16, 1903–1925, https://doi.org/10.5194/tc-16-1903-2022, https://doi.org/10.5194/tc-16-1903-2022, 2022
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We extend the application of electrical methods to characterize alpine permafrost using the so-called induced polarization (IP) effect associated with the storage of charges at the interface between liquid and solid phases. We investigate different field protocols to enhance data quality and conclude that with appropriate measurement and processing procedures, the characteristic dependence of the IP response of frozen rocks improves the assessment of thermal state and ice content in permafrost.
Christin Hilbich, Christian Hauck, Coline Mollaret, Pablo Wainstein, and Lukas U. Arenson
The Cryosphere, 16, 1845–1872, https://doi.org/10.5194/tc-16-1845-2022, https://doi.org/10.5194/tc-16-1845-2022, 2022
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In view of water scarcity in the Andes, the significance of permafrost as a future water resource is often debated focusing on satellite-detected features such as rock glaciers. We present data from > 50 geophysical surveys in Chile and Argentina to quantify the ground ice volume stored in various permafrost landforms, showing that not only rock glacier but also non-rock-glacier permafrost contains significant ground ice volumes and is relevant when assessing the hydrological role of permafrost.
Noah D. Smith, Eleanor J. Burke, Kjetil Schanke Aas, Inge H. J. Althuizen, Julia Boike, Casper Tai Christiansen, Bernd Etzelmüller, Thomas Friborg, Hanna Lee, Heather Rumbold, Rachael H. Turton, Sebastian Westermann, and Sarah E. Chadburn
Geosci. Model Dev., 15, 3603–3639, https://doi.org/10.5194/gmd-15-3603-2022, https://doi.org/10.5194/gmd-15-3603-2022, 2022
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The Arctic has large areas of small mounds that are caused by ice lifting up the soil. Snow blown by wind gathers in hollows next to these mounds, insulating them in winter. The hollows tend to be wetter, and thus the soil absorbs more heat in summer. The warm wet soil in the hollows decomposes, releasing methane. We have made a model of this, and we have tested how it behaves and whether it looks like sites in Scandinavia and Siberia. Sometimes we get more methane than a model without mounds.
Martin Hoelzle, Christian Hauck, Tamara Mathys, Jeannette Noetzli, Cécile Pellet, and Martin Scherler
Earth Syst. Sci. Data, 14, 1531–1547, https://doi.org/10.5194/essd-14-1531-2022, https://doi.org/10.5194/essd-14-1531-2022, 2022
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With ongoing climate change, it is crucial to understand the interactions of the individual heat fluxes at the surface and within the subsurface layers, as well as their impacts on the permafrost thermal regime. A unique set of high-altitude meteorological measurements has been analysed to determine the energy balance at three mountain permafrost sites in the Swiss Alps, where data have been collected since the late 1990s in collaboration with the Swiss Permafrost Monitoring Network (PERMOS).
Sarah E. Chadburn, Eleanor J. Burke, Angela V. Gallego-Sala, Noah D. Smith, M. Syndonia Bret-Harte, Dan J. Charman, Julia Drewer, Colin W. Edgar, Eugenie S. Euskirchen, Krzysztof Fortuniak, Yao Gao, Mahdi Nakhavali, Włodzimierz Pawlak, Edward A. G. Schuur, and Sebastian Westermann
Geosci. Model Dev., 15, 1633–1657, https://doi.org/10.5194/gmd-15-1633-2022, https://doi.org/10.5194/gmd-15-1633-2022, 2022
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We present a new method to include peatlands in an Earth system model (ESM). Peatlands store huge amounts of carbon that accumulates very slowly but that can be rapidly destabilised, emitting greenhouse gases. Our model captures the dynamic nature of peat by simulating the change in surface height and physical properties of the soil as carbon is added or decomposed. Thus, we model, for the first time in an ESM, peat dynamics and its threshold behaviours that can lead to destabilisation.
Bernd Etzelmüller, Justyna Czekirda, Florence Magnin, Pierre-Allain Duvillard, Ludovic Ravanel, Emanuelle Malet, Andreas Aspaas, Lene Kristensen, Ingrid Skrede, Gudrun D. Majala, Benjamin Jacobs, Johannes Leinauer, Christian Hauck, Christin Hilbich, Martina Böhme, Reginald Hermanns, Harald Ø. Eriksen, Tom Rune Lauknes, Michael Krautblatter, and Sebastian Westermann
Earth Surf. Dynam., 10, 97–129, https://doi.org/10.5194/esurf-10-97-2022, https://doi.org/10.5194/esurf-10-97-2022, 2022
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This paper is a multi-authored study documenting the possible existence of permafrost in permanently monitored rockslides in Norway for the first time by combining a multitude of field data, including geophysical surveys in rock walls. The paper discusses the possible role of thermal regime and rockslide movement, and it evaluates the possible impact of atmospheric warming on rockslide dynamics in Norwegian mountains.
Adrian Wicki, Per-Erik Jansson, Peter Lehmann, Christian Hauck, and Manfred Stähli
Hydrol. Earth Syst. Sci., 25, 4585–4610, https://doi.org/10.5194/hess-25-4585-2021, https://doi.org/10.5194/hess-25-4585-2021, 2021
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Soil moisture information was shown to be valuable for landslide prediction. Soil moisture was simulated at 133 sites in Switzerland, and the temporal variability was compared to the regional occurrence of landslides. We found that simulated soil moisture is a good predictor for landslides, and that the forecast goodness is similar to using in situ measurements. This encourages the use of models for complementing existing soil moisture monitoring networks for regional landslide early warning.
Léo C. P. Martin, Jan Nitzbon, Johanna Scheer, Kjetil S. Aas, Trond Eiken, Moritz Langer, Simon Filhol, Bernd Etzelmüller, and Sebastian Westermann
The Cryosphere, 15, 3423–3442, https://doi.org/10.5194/tc-15-3423-2021, https://doi.org/10.5194/tc-15-3423-2021, 2021
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It is important to understand how permafrost landscapes respond to climate changes because their thaw can contribute to global warming. We investigate how a common permafrost morphology degrades using both field observations of the surface elevation and numerical modeling. We show that numerical models accounting for topographic changes related to permafrost degradation can reproduce the observed changes in nature and help us understand how parameters such as snow influence this phenomenon.
Juditha Undine Schmidt, Bernd Etzelmüller, Thomas Vikhamar Schuler, Florence Magnin, Julia Boike, Moritz Langer, and Sebastian Westermann
The Cryosphere, 15, 2491–2509, https://doi.org/10.5194/tc-15-2491-2021, https://doi.org/10.5194/tc-15-2491-2021, 2021
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This study presents rock surface temperatures (RSTs) of steep high-Arctic rock walls on Svalbard from 2016 to 2020. The field data show that coastal cliffs are characterized by warmer RSTs than inland locations during winter seasons. By running model simulations, we analyze factors leading to that effect, calculate the surface energy balance and simulate different future scenarios. Both field data and model results can contribute to a further understanding of RST in high-Arctic rock walls.
Thomas Schneider von Deimling, Hanna Lee, Thomas Ingeman-Nielsen, Sebastian Westermann, Vladimir Romanovsky, Scott Lamoureux, Donald A. Walker, Sarah Chadburn, Erin Trochim, Lei Cai, Jan Nitzbon, Stephan Jacobi, and Moritz Langer
The Cryosphere, 15, 2451–2471, https://doi.org/10.5194/tc-15-2451-2021, https://doi.org/10.5194/tc-15-2451-2021, 2021
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Climate warming puts infrastructure built on permafrost at risk of failure. There is a growing need for appropriate model-based risk assessments. Here we present a modelling study and show an exemplary case of how a gravel road in a cold permafrost environment in Alaska might suffer from degrading permafrost under a scenario of intense climate warming. We use this case study to discuss the broader-scale applicability of our model for simulating future Arctic infrastructure failure.
Jan Nitzbon, Moritz Langer, Léo C. P. Martin, Sebastian Westermann, Thomas Schneider von Deimling, and Julia Boike
The Cryosphere, 15, 1399–1422, https://doi.org/10.5194/tc-15-1399-2021, https://doi.org/10.5194/tc-15-1399-2021, 2021
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We used a numerical model to investigate how small-scale landscape heterogeneities affect permafrost thaw under climate-warming scenarios. Our results show that representing small-scale heterogeneities in the model can decide whether a landscape is water-logged or well-drained in the future. This in turn affects how fast permafrost thaws under warming. Our research emphasizes the importance of considering small-scale processes in model assessments of permafrost thaw under climate change.
Christian Halla, Jan Henrik Blöthe, Carla Tapia Baldis, Dario Trombotto Liaudat, Christin Hilbich, Christian Hauck, and Lothar Schrott
The Cryosphere, 15, 1187–1213, https://doi.org/10.5194/tc-15-1187-2021, https://doi.org/10.5194/tc-15-1187-2021, 2021
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In the semi-arid to arid Andes of Argentina, rock glaciers contain invisible and unknown amounts of ground ice that could become more important in future for the water availability during the dry season. The study shows that the investigated rock glacier represents an important long-term ice reservoir in the dry mountain catchment and that interannual changes of ground ice can store and release significant amounts of annual precipitation.
Simone Maria Stuenzi, Julia Boike, William Cable, Ulrike Herzschuh, Stefan Kruse, Luidmila A. Pestryakova, Thomas Schneider von Deimling, Sebastian Westermann, Evgenii S. Zakharov, and Moritz Langer
Biogeosciences, 18, 343–365, https://doi.org/10.5194/bg-18-343-2021, https://doi.org/10.5194/bg-18-343-2021, 2021
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Boreal forests in eastern Siberia are an essential component of global climate patterns. We use a physically based model and field measurements to study the interactions between forests, permanently frozen ground and the atmosphere. We find that forests exert a strong control on the thermal state of permafrost through changing snow cover dynamics and altering the surface energy balance, through absorbing most of the incoming solar radiation and suppressing below-canopy turbulent fluxes.
Lei Cai, Hanna Lee, Kjetil Schanke Aas, and Sebastian Westermann
The Cryosphere, 14, 4611–4626, https://doi.org/10.5194/tc-14-4611-2020, https://doi.org/10.5194/tc-14-4611-2020, 2020
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A sub-grid representation of excess ground ice in the Community Land Model (CLM) is developed as novel progress in modeling permafrost thaw and its impacts under the warming climate. The modeled permafrost degradation with sub-grid excess ice follows the pathway that continuous permafrost transforms into discontinuous permafrost before it disappears, including surface subsidence and talik formation, which are highly permafrost-relevant landscape changes excluded from most land models.
Maximilian Weigand, Florian M. Wagner, Jonas K. Limbrock, Christin Hilbich, Christian Hauck, and Andreas Kemna
Geosci. Instrum. Method. Data Syst., 9, 317–336, https://doi.org/10.5194/gi-9-317-2020, https://doi.org/10.5194/gi-9-317-2020, 2020
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In times of global warming, permafrost is starting to degrade at alarming rates, requiring new and improved characterization approaches. We describe the design and test installation, as well as detailed data quality assessment, of a monitoring system used to capture natural electrical potentials in the subsurface. These self-potential signals are of great interest for the noninvasive investigation of water flow in the non-frozen or partially frozen subsurface.
Anita Verpe Dyrrdal, Ketil Isaksen, Jens Kristian Steen Jacobsen, and Irene Brox Nilsen
Nat. Hazards Earth Syst. Sci., 20, 1847–1865, https://doi.org/10.5194/nhess-20-1847-2020, https://doi.org/10.5194/nhess-20-1847-2020, 2020
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We have studied changes in winter weather known to trigger road closures and isolation of small seaside communities in northern Norway. We find that snow amounts and heavy snowfall events have increased in the past, while future projections for 2040–2100 show a decrease in snow-related indices. Events of heavy water supply and zero crossings are expected to increase. Our results imply fewer dry-snow-related access disruptions in the future, while wet-snow avalanches and slushflows may increase.
Mohammad Farzamian, Gonçalo Vieira, Fernando A. Monteiro Santos, Borhan Yaghoobi Tabar, Christian Hauck, Maria Catarina Paz, Ivo Bernardo, Miguel Ramos, and Miguel Angel de Pablo
The Cryosphere, 14, 1105–1120, https://doi.org/10.5194/tc-14-1105-2020, https://doi.org/10.5194/tc-14-1105-2020, 2020
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A 2-D automated electrical resistivity tomography (A-ERT) system was installed for the first time in Antarctica at Deception Island to (i) monitor subsurface freezing and thawing processes on a daily and seasonal basis and map the spatial and temporal variability of thaw depth and to (ii) study the impact of short-lived extreme meteorological events on active layer dynamics.
Jaroslav Obu, Sebastian Westermann, Gonçalo Vieira, Andrey Abramov, Megan Ruby Balks, Annett Bartsch, Filip Hrbáček, Andreas Kääb, and Miguel Ramos
The Cryosphere, 14, 497–519, https://doi.org/10.5194/tc-14-497-2020, https://doi.org/10.5194/tc-14-497-2020, 2020
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Little is known about permafrost in the Antarctic outside of the few research stations. We used a simple equilibrium permafrost model to estimate permafrost temperatures in the whole Antarctic. The lowest permafrost temperature on Earth is −36 °C in the Queen Elizabeth Range in the Transantarctic Mountains. Temperatures are commonly between −23 and −18 °C in mountainous areas rising above the Antarctic Ice Sheet, between −14 and −8 °C in coastal areas, and up to 0 °C on the Antarctic Peninsula.
Joel Fiddes, Kristoffer Aalstad, and Sebastian Westermann
Hydrol. Earth Syst. Sci., 23, 4717–4736, https://doi.org/10.5194/hess-23-4717-2019, https://doi.org/10.5194/hess-23-4717-2019, 2019
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In this paper we address one of the big challenges in snow hydrology, namely the accurate simulation of the seasonal snowpack in ungauged regions. We do this by assimilating satellite observations of snow cover into a modelling framework. Importantly (and a novelty of the paper), we include a clustering approach that permits highly efficient ensemble simulations. Efficiency gains and dependency on purely global datasets, means that this method can be applied over large areas anywhere on Earth.
Florence Magnin, Bernd Etzelmüller, Sebastian Westermann, Ketil Isaksen, Paula Hilger, and Reginald L. Hermanns
Earth Surf. Dynam., 7, 1019–1040, https://doi.org/10.5194/esurf-7-1019-2019, https://doi.org/10.5194/esurf-7-1019-2019, 2019
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This study proposes the first permafrost (i.e. ground with temperature permanently < 0 °C) map covering the steep rock slopes of Norway. It was created by using rock temperature data collected at the near surface of 25 rock walls spread across the country between 2010 and 2018. The map shows that permafrost mostly exists above 1300–1400 m a.s.l. in southern Norway and close to sea level in northern Norway. The results have strong potential for the study of rock wall sliding and failure.
Lei Cai, Hanna Lee, Sebastian Westermann, and Kjetil Schanke Aas
The Cryosphere Discuss., https://doi.org/10.5194/tc-2019-230, https://doi.org/10.5194/tc-2019-230, 2019
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We develop a sub-grid representation of excess ground ice in the Community Land Model (CLM) by adding three landunits to the original CLM sub-grid hierarchy, in order to prescribe three different excess ice conditions in one grid cell. Single-grid simulations verify the potential of the model development on better projecting excess ice melt in a warming climate. Global simulations recommend the proper way of applying the model development with the existing excess ice dataset.
Coline Mollaret, Christin Hilbich, Cécile Pellet, Adrian Flores-Orozco, Reynald Delaloye, and Christian Hauck
The Cryosphere, 13, 2557–2578, https://doi.org/10.5194/tc-13-2557-2019, https://doi.org/10.5194/tc-13-2557-2019, 2019
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We present a long-term multisite electrical resistivity tomography monitoring network (more than 1000 datasets recorded from six mountain permafrost sites). Despite harsh and remote measurement conditions, the datasets are of good quality and show consistent spatio-temporal variations yielding significant added value to point-scale borehole information. Observed long-term trends are similar for all permafrost sites, showing ongoing permafrost thaw and ground ice loss due to climatic conditions.
Jan Mudler, Andreas Hördt, Anita Przyklenk, Gianluca Fiandaca, Pradip Kumar Maurya, and Christian Hauck
The Cryosphere, 13, 2439–2456, https://doi.org/10.5194/tc-13-2439-2019, https://doi.org/10.5194/tc-13-2439-2019, 2019
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The capacitively coupled resistivity (CCR) method enables the determination of frequency-dependent electrical parameters of the subsurface. CCR is well suited for application in cryospheric areas because it provides logistical advantages regarding coupling on hard surfaces and highly resistive grounds. With our new spectral two-dimensional inversion, we can identify subsurface structures based on full spectral information. We show the first results of the inversion method on the field scale.
Jan Nitzbon, Moritz Langer, Sebastian Westermann, Léo Martin, Kjetil Schanke Aas, and Julia Boike
The Cryosphere, 13, 1089–1123, https://doi.org/10.5194/tc-13-1089-2019, https://doi.org/10.5194/tc-13-1089-2019, 2019
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We studied the stability of ice wedges (massive bodies of ground ice in permafrost) under recent climatic conditions in the Lena River delta of northern Siberia. For this we used a novel modelling approach that takes into account lateral transport of heat, water, and snow and the subsidence of the ground surface due to melting of ground ice. We found that wetter conditions have a destabilizing effect on the ice wedges and associated our simulation results with observations from the study area.
Kjetil S. Aas, Léo Martin, Jan Nitzbon, Moritz Langer, Julia Boike, Hanna Lee, Terje K. Berntsen, and Sebastian Westermann
The Cryosphere, 13, 591–609, https://doi.org/10.5194/tc-13-591-2019, https://doi.org/10.5194/tc-13-591-2019, 2019
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Many permafrost landscapes contain large amounts of excess ground ice, which gives rise to small-scale elevation differences. This results in lateral fluxes of snow, water, and heat, which we investigate and show how it can be accounted for in large-scale models. Using a novel model technique which can account for these differences, we are able to model both the current state of permafrost and how these landscapes change as permafrost thaws, in a way that could not previously be achieved.
Regula Frauenfelder, Ketil Isaksen, Matthew J. Lato, and Jeannette Noetzli
The Cryosphere, 12, 1531–1550, https://doi.org/10.5194/tc-12-1531-2018, https://doi.org/10.5194/tc-12-1531-2018, 2018
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On 26 June 2008, a rock avalanche with a volume of ca. 500 000 m3 detached in the north-east facing slope of Polvartinden, a high-alpine peak in northern Norway. Ice was observed in the failure zone shortly after the rock avalanche, leading to the assumption that degrading permafrost might have played an important role in the detaching of the Signaldalen rock avalanche. Here, we present a four-year series of temperature measurements from the site and subsequent temperature modelling results.
Julia Boike, Inge Juszak, Stephan Lange, Sarah Chadburn, Eleanor Burke, Pier Paul Overduin, Kurt Roth, Olaf Ippisch, Niko Bornemann, Lielle Stern, Isabelle Gouttevin, Ernst Hauber, and Sebastian Westermann
Earth Syst. Sci. Data, 10, 355–390, https://doi.org/10.5194/essd-10-355-2018, https://doi.org/10.5194/essd-10-355-2018, 2018
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A 20-year data record from the Bayelva site at Ny-Ålesund, Svalbard, is presented on meteorology, energy balance components, surface and subsurface observations. This paper presents the data set, instrumentation, calibration, processing and data quality control. The data show that mean annual, summer and winter soil temperature data from shallow to deeper depths have been warming over the period of record, indicating the degradation and loss of permafrost at this site.
Martin Beniston, Daniel Farinotti, Markus Stoffel, Liss M. Andreassen, Erika Coppola, Nicolas Eckert, Adriano Fantini, Florie Giacona, Christian Hauck, Matthias Huss, Hendrik Huwald, Michael Lehning, Juan-Ignacio López-Moreno, Jan Magnusson, Christoph Marty, Enrique Morán-Tejéda, Samuel Morin, Mohamed Naaim, Antonello Provenzale, Antoine Rabatel, Delphine Six, Johann Stötter, Ulrich Strasser, Silvia Terzago, and Christian Vincent
The Cryosphere, 12, 759–794, https://doi.org/10.5194/tc-12-759-2018, https://doi.org/10.5194/tc-12-759-2018, 2018
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This paper makes a rather exhaustive overview of current knowledge of past, current, and future aspects of cryospheric issues in continental Europe and makes a number of reflections of areas of uncertainty requiring more attention in both scientific and policy terms. The review paper is completed by a bibliography containing 350 recent references that will certainly be of value to scholars engaged in the fields of glacier, snow, and permafrost research.
John Kochendorfer, Rodica Nitu, Mareile Wolff, Eva Mekis, Roy Rasmussen, Bruce Baker, Michael E. Earle, Audrey Reverdin, Kai Wong, Craig D. Smith, Daqing Yang, Yves-Alain Roulet, Tilden Meyers, Samuel Buisan, Ketil Isaksen, Ragnar Brækkan, Scott Landolt, and Al Jachcik
Hydrol. Earth Syst. Sci., 22, 1437–1452, https://doi.org/10.5194/hess-22-1437-2018, https://doi.org/10.5194/hess-22-1437-2018, 2018
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Due to the effects of wind, precipitation gauges typically underestimate the amount of precipitation that occurs as snow. Measurements recorded during a World Meteorological Organization intercomparison of precipitation gauges were used to evaluate and improve the adjustments that are available to address this issue. Adjustments for specific types of precipitation gauges and wind shields were tested and recommended.
Kristoffer Aalstad, Sebastian Westermann, Thomas Vikhamar Schuler, Julia Boike, and Laurent Bertino
The Cryosphere, 12, 247–270, https://doi.org/10.5194/tc-12-247-2018, https://doi.org/10.5194/tc-12-247-2018, 2018
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We demonstrate how snow cover data from satellites can be used to constrain estimates of snow distributions at sites in the Arctic. In this effort, we make use of data assimilation to combine the information contained in the snow cover data with a simple snow model. By comparing our snow distribution estimates to independent observations, we find that this method performs favorably. Being modular, this method could be applied to other areas as a component of a larger reanalysis system.
Regula Frauenfelder, Anders Solheim, Ketil Isaksen, Bård Romstad, Anita V. Dyrrdal, Kristine H. H. Ekseth, Alf Harbitz, Carl B. Harbitz, Jan Erik Haugen, Hans Olav Hygen, Hilde Haakenstad, Christian Jaedicke, Árni Jónsson, Ronny Klæboe, Johanna Ludvigsen, Nele M. Meyer, Trude Rauken, Reidun G. Skaland, Kjetil Sverdrup-Thygeson, Asbjørn Aaheim, Heidi Bjordal, and Per-Anton Fevang
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhess-2017-437, https://doi.org/10.5194/nhess-2017-437, 2017
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We present results from the project
Impacts of extreme weather events on infrastructure in Norway. Our analyses document an increase in frequency and intensity of e.g. precipitation and wind during the last decades, and that these observed changes will continue throughout the 21st century. We could show that ≥ 27 % of main roads and 31 % of railroads are exposed to rockfall and avalanches. Pro-actively facing such risks will increase resilience and cost-efficiency of the transport infrastructure.
Benjamin Mewes, Christin Hilbich, Reynald Delaloye, and Christian Hauck
The Cryosphere, 11, 2957–2974, https://doi.org/10.5194/tc-11-2957-2017, https://doi.org/10.5194/tc-11-2957-2017, 2017
Sarah E. Chadburn, Gerhard Krinner, Philipp Porada, Annett Bartsch, Christian Beer, Luca Belelli Marchesini, Julia Boike, Altug Ekici, Bo Elberling, Thomas Friborg, Gustaf Hugelius, Margareta Johansson, Peter Kuhry, Lars Kutzbach, Moritz Langer, Magnus Lund, Frans-Jan W. Parmentier, Shushi Peng, Ko Van Huissteden, Tao Wang, Sebastian Westermann, Dan Zhu, and Eleanor J. Burke
Biogeosciences, 14, 5143–5169, https://doi.org/10.5194/bg-14-5143-2017, https://doi.org/10.5194/bg-14-5143-2017, 2017
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Earth system models (ESMs) are our main tools for understanding future climate. The Arctic is important for the future carbon cycle, particularly due to the large carbon stocks in permafrost. We evaluated the performance of the land component of three major ESMs at Arctic tundra sites, focusing on the fluxes and stocks of carbon.
We show that the next steps for model improvement are to better represent vegetation dynamics, to include mosses and to improve below-ground carbon cycle processes.
John Kochendorfer, Rodica Nitu, Mareile Wolff, Eva Mekis, Roy Rasmussen, Bruce Baker, Michael E. Earle, Audrey Reverdin, Kai Wong, Craig D. Smith, Daqing Yang, Yves-Alain Roulet, Samuel Buisan, Timo Laine, Gyuwon Lee, Jose Luis C. Aceituno, Javier Alastrué, Ketil Isaksen, Tilden Meyers, Ragnar Brækkan, Scott Landolt, Al Jachcik, and Antti Poikonen
Hydrol. Earth Syst. Sci., 21, 3525–3542, https://doi.org/10.5194/hess-21-3525-2017, https://doi.org/10.5194/hess-21-3525-2017, 2017
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Precipitation measurements were combined from eight separate precipitation testbeds to create multi-site transfer functions for the correction of unshielded and single-Alter-shielded precipitation gauge measurements. Site-specific errors and more universally applicable corrections were created from these WMO-SPICE measurements. The importance and magnitude of such wind speed corrections were demonstrated.
Cécile Pellet and Christian Hauck
Hydrol. Earth Syst. Sci., 21, 3199–3220, https://doi.org/10.5194/hess-21-3199-2017, https://doi.org/10.5194/hess-21-3199-2017, 2017
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This paper presents a detailed description of the new Swiss soil moisture monitoring network SOMOMOUNT, which comprises six stations distributed along an elevation gradient ranging from 1205 to 3410 m. The liquid soil moisture (LSM) data collected during the first 3 years are discussed with regard to their soil type and climate dependency as well as their altitudinal distribution. The elevation dependency of the LSM was found to be non-linear with distinct dynamics at high and low elevation.
Sebastian Westermann, Maria Peter, Moritz Langer, Georg Schwamborn, Lutz Schirrmeister, Bernd Etzelmüller, and Julia Boike
The Cryosphere, 11, 1441–1463, https://doi.org/10.5194/tc-11-1441-2017, https://doi.org/10.5194/tc-11-1441-2017, 2017
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We demonstrate a remote-sensing-based scheme estimating the evolution of ground temperature and active layer thickness by means of a ground thermal model. A comparison to in situ observations from the Lena River delta in Siberia indicates that the model is generally capable of reproducing the annual temperature regime and seasonal thawing of the ground. The approach could hence be a first step towards remote detection of ground thermal conditions in permafrost areas.
Jonas Wicky and Christian Hauck
The Cryosphere, 11, 1311–1325, https://doi.org/10.5194/tc-11-1311-2017, https://doi.org/10.5194/tc-11-1311-2017, 2017
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Talus slopes are a widespread geomorphic feature, which may show permafrost conditions even at low elevation due to cold microclimates induced by a gravity-driven internal air circulation. We show for the first time a numerical simulation of this internal air circulation of a field-scale talus slope. Results indicate that convective heat transfer leads to a pronounced ground cooling in the lower part of the talus slope favoring the persistence of permafrost.
John Kochendorfer, Roy Rasmussen, Mareile Wolff, Bruce Baker, Mark E. Hall, Tilden Meyers, Scott Landolt, Al Jachcik, Ketil Isaksen, Ragnar Brækkan, and Ronald Leeper
Hydrol. Earth Syst. Sci., 21, 1973–1989, https://doi.org/10.5194/hess-21-1973-2017, https://doi.org/10.5194/hess-21-1973-2017, 2017
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Snowfall measurements recorded using precipitation gauges are subject to significant underestimation due to the effects of wind. Using measurements recorded at two different precipitation test beds, corrections for unshielded gauges and gauges within different types of windshields were developed and tested. Using the new corrections, uncorrectable errors were quantified, and measurement biases were successfully eliminated.
Luc Girod, Christopher Nuth, Andreas Kääb, Bernd Etzelmüller, and Jack Kohler
The Cryosphere, 11, 827–840, https://doi.org/10.5194/tc-11-827-2017, https://doi.org/10.5194/tc-11-827-2017, 2017
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While gathering data on a changing environment is often a costly and complicated endeavour, it is also the backbone of all research. What if one could measure elevation change by just strapping a camera and a hiking GPS under an helicopter or a small airplane used for transportation and gather data on the ground bellow the flight path? In this article, we present a way to do exactly that and show an example survey where it helped compute the volume of ice lost by a glacier in Svalbard.
Amund F. Borge, Sebastian Westermann, Ingvild Solheim, and Bernd Etzelmüller
The Cryosphere, 11, 1–16, https://doi.org/10.5194/tc-11-1-2017, https://doi.org/10.5194/tc-11-1-2017, 2017
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Palsas and peat plateaus are permafrost landforms in subarctic mires which constitute sensitive ecosystems with strong significance for vegetation, wildlife, hydrology and carbon cycle. We have systematically mapped the occurrence of palsas and peat plateaus in northern Norway by interpretation of aerial images from the 1950s until today. The results show that about half of the area of palsas and peat plateaus has disappeared due to lateral erosion and melting of ground ice in the last 50 years.
Rune Strand Ødegård, Atle Nesje, Ketil Isaksen, Liss Marie Andreassen, Trond Eiken, Margit Schwikowski, and Chiara Uglietti
The Cryosphere, 11, 17–32, https://doi.org/10.5194/tc-11-17-2017, https://doi.org/10.5194/tc-11-17-2017, 2017
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Despite numerous spectacular archaeological discoveries worldwide related to melting ice, governing processes related to ice patch development are still largely unexplored. We present new results from Jotunheimen in central southern Norway showing that the Juvfonne ice patch has existed continuously since ca. 7600 cal years BP. This is the oldest dating of ice in mainland Norway. Moss mats along the margin of Juvfonne in 2014 were covered by the expanding ice patch about 2000 years ago.
Antoine Marmy, Jan Rajczak, Reynald Delaloye, Christin Hilbich, Martin Hoelzle, Sven Kotlarski, Christophe Lambiel, Jeannette Noetzli, Marcia Phillips, Nadine Salzmann, Benno Staub, and Christian Hauck
The Cryosphere, 10, 2693–2719, https://doi.org/10.5194/tc-10-2693-2016, https://doi.org/10.5194/tc-10-2693-2016, 2016
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This paper presents a new semi-automated method to calibrate the 1-D soil model COUP. It is the first time (as far as we know) that this approach is developed for mountain permafrost. It is applied at six test sites in the Swiss Alps. In a second step, the calibrated model is used for RCM-based simulations with specific downscaling of RCM data to the borehole scale. We show projections of the permafrost evolution at the six sites until the end of the century and according to the A1B scenario.
Kjersti Gisnås, Sebastian Westermann, Thomas Vikhamar Schuler, Kjetil Melvold, and Bernd Etzelmüller
The Cryosphere, 10, 1201–1215, https://doi.org/10.5194/tc-10-1201-2016, https://doi.org/10.5194/tc-10-1201-2016, 2016
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In wind exposed areas snow redistribution results in large spatial variability in ground temperatures. In these areas, the ground temperature of a grid cell must be determined based on the distribution, and not the average, of snow depths. We employ distribution functions of snow in a regional permafrost model, showing highly improved representation of ground temperatures. By including snow distributions, we find the permafrost area to be nearly twice as large as what is modelled without.
S. Westermann, M. Langer, J. Boike, M. Heikenfeld, M. Peter, B. Etzelmüller, and G. Krinner
Geosci. Model Dev., 9, 523–546, https://doi.org/10.5194/gmd-9-523-2016, https://doi.org/10.5194/gmd-9-523-2016, 2016
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Thawing of permafrost is governed by a complex interplay of different processes, of which only conductive heat transfer is taken into account in most model studies. We present a new land-surface scheme designed for permafrost applications, CryoGrid 3, which constitutes a flexible platform to explore new parameterizations for a range of permafrost processes.
A. Ekici, S. Chadburn, N. Chaudhary, L. H. Hajdu, A. Marmy, S. Peng, J. Boike, E. Burke, A. D. Friend, C. Hauck, G. Krinner, M. Langer, P. A. Miller, and C. Beer
The Cryosphere, 9, 1343–1361, https://doi.org/10.5194/tc-9-1343-2015, https://doi.org/10.5194/tc-9-1343-2015, 2015
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This paper compares the performance of different land models in estimating soil thermal regimes at distinct cold region landscape types. Comparing models with different processes reveal the importance of surface insulation (snow/moss layer) and soil internal processes (heat/water transfer). The importance of model processes also depend on site conditions such as high/low snow cover, dry/wet soil types.
S. Westermann, T. I. Østby, K. Gisnås, T. V. Schuler, and B. Etzelmüller
The Cryosphere, 9, 1303–1319, https://doi.org/10.5194/tc-9-1303-2015, https://doi.org/10.5194/tc-9-1303-2015, 2015
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We use remotely sensed land surface temperature and land cover in conjunction with air temperature and snowfall from a reanalysis product as input for a simple permafrost model. The scheme is applied to the permafrost regions bordering the North Atlantic. A comparison with ground temperatures in boreholes suggests a modeling accuracy of 2 to 2.5 °C.
S. Westermann, B. Elberling, S. Højlund Pedersen, M. Stendel, B. U. Hansen, and G. E. Liston
The Cryosphere, 9, 719–735, https://doi.org/10.5194/tc-9-719-2015, https://doi.org/10.5194/tc-9-719-2015, 2015
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The development of ground temperatures in permafrost areas is influenced by many factors varying on different spatial and temporal scales. We present numerical simulations of ground temperatures for the Zackenberg valley in NE Greenland, which take into account the spatial variability of snow depths, surface and ground properties at a scale of 10m. The ensemble of the model grid cells suggests a spatial variability of annual average ground temperatures of up to 5°C.
P. Pogliotti, M. Guglielmin, E. Cremonese, U. Morra di Cella, G. Filippa, C. Pellet, and C. Hauck
The Cryosphere, 9, 647–661, https://doi.org/10.5194/tc-9-647-2015, https://doi.org/10.5194/tc-9-647-2015, 2015
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This study presents the thermal state and recent evolution of permafrost at Cime Bianche.
The analysis reveals that (i) spatial variability of MAGST is greater than its interannual variability and is controlled by snow duration and air temperature during the snow-free period, (ii) the ALT has a pronounced spatial variability caused by a different subsurface ice and water content, and (iii) permafrost is warming at significant rates below 8m of depth.
B. Staub, A. Marmy, C. Hauck, C. Hilbich, and R. Delaloye
Geogr. Helv., 70, 45–62, https://doi.org/10.5194/gh-70-45-2015, https://doi.org/10.5194/gh-70-45-2015, 2015
M. A. Wolff, K. Isaksen, A. Petersen-Øverleir, K. Ødemark, T. Reitan, and R. Brækkan
Hydrol. Earth Syst. Sci., 19, 951–967, https://doi.org/10.5194/hess-19-951-2015, https://doi.org/10.5194/hess-19-951-2015, 2015
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The article reports on measurements, analysis and results of a Norwegian field study aimed to adjust automatic precipitation measurements for under-catch during windy conditions. An unique data set could be collected, documenting the under-catch of snow at very high wind speeds for the first time. A new continuous adjustment function for precipitation measured by an automated gauge covering all three precipitation types (snow, mixed and rain) was established.
M. Langer, S. Westermann, K. Walter Anthony, K. Wischnewski, and J. Boike
Biogeosciences, 12, 977–990, https://doi.org/10.5194/bg-12-977-2015, https://doi.org/10.5194/bg-12-977-2015, 2015
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Methane production rates of Arctic ponds during the freezing period within a typical tundra landscape in northern Siberia are presented. Production rates were inferred by inverse modeling based on measured methane concentrations in the ice cover. Results revealed marked differences in early winter methane production among ponds showing different stages of shore degradation. This suggests that shore erosion can increase methane production of Arctic ponds by 2 to 3 orders of magnitude.
J. Lüers, S. Westermann, K. Piel, and J. Boike
Biogeosciences, 11, 6307–6322, https://doi.org/10.5194/bg-11-6307-2014, https://doi.org/10.5194/bg-11-6307-2014, 2014
K. Gisnås, S. Westermann, T. V. Schuler, T. Litherland, K. Isaksen, J. Boike, and B. Etzelmüller
The Cryosphere, 8, 2063–2074, https://doi.org/10.5194/tc-8-2063-2014, https://doi.org/10.5194/tc-8-2063-2014, 2014
A. Ekici, C. Beer, S. Hagemann, J. Boike, M. Langer, and C. Hauck
Geosci. Model Dev., 7, 631–647, https://doi.org/10.5194/gmd-7-631-2014, https://doi.org/10.5194/gmd-7-631-2014, 2014
M. Scherler, S. Schneider, M. Hoelzle, and C. Hauck
Earth Surf. Dynam., 2, 141–154, https://doi.org/10.5194/esurf-2-141-2014, https://doi.org/10.5194/esurf-2-141-2014, 2014
S. Schneider, S. Daengeli, C. Hauck, and M. Hoelzle
Geogr. Helv., 68, 265–280, https://doi.org/10.5194/gh-68-265-2013, https://doi.org/10.5194/gh-68-265-2013, 2013
S. Westermann, T. V. Schuler, K. Gisnås, and B. Etzelmüller
The Cryosphere, 7, 719–739, https://doi.org/10.5194/tc-7-719-2013, https://doi.org/10.5194/tc-7-719-2013, 2013
Related subject area
Discipline: Frozen ground | Subject: Mountain Processes
Quantifying frost-weathering-induced damage in alpine rocks
Mountain permafrost in the Central Pyrenees: insights from the Devaux ice cave
Glacier–permafrost relations in a high-mountain environment: 5 decades of kinematic monitoring at the Gruben site, Swiss Alps
Brief communication: The influence of mica-rich rocks on the shear strength of ice-filled discontinuities
Resolving the influence of temperature forcing through heat conduction on rock glacier dynamics: a numerical modelling approach
A temperature- and stress-controlled failure criterion for ice-filled permafrost rock joints
Till Mayer, Maxim Deprez, Laurenz Schröer, Veerle Cnudde, and Daniel Draebing
The Cryosphere, 18, 2847–2864, https://doi.org/10.5194/tc-18-2847-2024, https://doi.org/10.5194/tc-18-2847-2024, 2024
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Frost weathering drives rockfall and shapes the evolution of alpine landscapes. We employed a novel combination of investigation techniques to assess the influence of different climatic conditions on high-alpine rock faces. Our results imply that rock walls exposed to freeze–thaw conditions, which are likely to occur at lower elevations, will weather more rapidly than rock walls exposed to sustained freezing conditions due to winter snow cover or permafrost at higher elevations.
Miguel Bartolomé, Gérard Cazenave, Marc Luetscher, Christoph Spötl, Fernando Gázquez, Ánchel Belmonte, Alexandra V. Turchyn, Juan Ignacio López-Moreno, and Ana Moreno
The Cryosphere, 17, 477–497, https://doi.org/10.5194/tc-17-477-2023, https://doi.org/10.5194/tc-17-477-2023, 2023
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In this work we study the microclimate and the geomorphological features of Devaux ice cave in the Central Pyrenees. The research is based on cave monitoring, geomorphology, and geochemical analyses. We infer two different thermal regimes. The cave is impacted by flooding in late winter/early spring when the main outlets freeze, damming the water inside. Rock temperatures below 0°C and the absence of drip water indicate frozen rock, while relict ice formations record past damming events.
Isabelle Gärtner-Roer, Nina Brunner, Reynald Delaloye, Wilfried Haeberli, Andreas Kääb, and Patrick Thee
The Cryosphere, 16, 2083–2101, https://doi.org/10.5194/tc-16-2083-2022, https://doi.org/10.5194/tc-16-2083-2022, 2022
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We intensely investigated the Gruben site in the Swiss Alps, where glaciers and permafrost landforms closely interact, to better understand cold-climate environments. By the interpretation of air photos from 5 decades, we describe long-term developments of the existing landforms. In combination with high-resolution positioning measurements and ground surface temperatures, we were also able to link these to short-term changes and describe different landform responses to climate forcing.
Philipp Mamot, Samuel Weber, Maximilian Lanz, and Michael Krautblatter
The Cryosphere, 14, 1849–1855, https://doi.org/10.5194/tc-14-1849-2020, https://doi.org/10.5194/tc-14-1849-2020, 2020
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A failure criterion for ice-filled rock joints is a prerequisite to accurately assess the stability of permafrost rock slopes. In 2018 a failure criterion was proposed based on limestone. Now, we tested the transferability to other rocks using mica schist and gneiss which provide the maximum expected deviation of lithological effects on the shear strength. We show that even for controversial rocks the failure criterion stays unaltered, suggesting that it is applicable to mostly all rock types.
Alessandro Cicoira, Jan Beutel, Jérome Faillettaz, Isabelle Gärtner-Roer, and Andreas Vieli
The Cryosphere, 13, 927–942, https://doi.org/10.5194/tc-13-927-2019, https://doi.org/10.5194/tc-13-927-2019, 2019
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Rock glacier flow varies on multiple timescales. The variations have been linked to climatic forcing, but a quantitative understanding is still missing.
We use a 1-D numerical modelling approach coupling heat conduction to a creep model in order to study the influence of temperature variations on rock glacier flow. Our results show that heat conduction alone cannot explain the observed variations. Other processes, likely linked to water, must dominate the short-term velocity signal.
Philipp Mamot, Samuel Weber, Tanja Schröder, and Michael Krautblatter
The Cryosphere, 12, 3333–3353, https://doi.org/10.5194/tc-12-3333-2018, https://doi.org/10.5194/tc-12-3333-2018, 2018
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Most of the observed failures in permafrost-affected alpine rock walls are likely triggered by the mechanical destabilisation of warming bedrock permafrost including ice-filled joints. We present a systematic study of the brittle shear failure of ice and rock–ice contacts along rock joints in a simulated depth ≤ 30 m and at temperatures from −10 to −0.5 °C. Warming and sudden reduction in rock overburden due to the detachment of an upper rock mass lead to a significant drop in shear resistance.
Cited articles
Andersen, J. L., Egholm, D. L., Knudsen, M. F., Jansen, J. D., and Nielsen, S. B.: The periglacial engine of mountain erosion – Part 1: Rates of frost cracking and frost creep, Earth Surf. Dynam., 3, 447–462, https://doi.org/10.5194/esurf-3-447-2015, 2015.
Arnalds, O.: The soils of Iceland, Springer, ISBN 9401796211, 2015.
Bengtsson, L., Andrae, U., Aspelien, T., Batrak, Y., Calvo, J., de Rooy, W., Gleeson, E., Hansen-Sass, B., Homleid, M., and Hortal, M.: The HARMONIE–AROME model configuration in the ALADIN–HIRLAM NWP system, Mon. Weather Rev., 145, 1919–1935, 2017.
Berthling, I. and Etzelmuller, B.: The concept of cryo-conditioning in landscape evolution, Quaternary Res., 75, 378–384, https://doi.org/10.1016/j.yqres.2010.12.011, 2011.
Biskaborn, B. K., Smith, S. L., Noetzli, J., Matthes, H., Vieira, G., Streletskiy, D. A., Schoeneich, P., Romanovsky, V. E., Lewkowicz, A. G., Abramov, A., Allard, M., Boike, J., Cable, W. L., Christiansen, H. H., Delaloye, R., Diekmann, B., Drozdov, D., Etzelmüller, B., Grosse, G., Guglielmin, M., Ingeman-Nielsen, T., Isaksen, K., Ishikawa, M., Johansson, M., Johannsson, H., Joo, A., Kaverin, D., Kholodov, A., Konstantinov, P., Kröger, T., Lambiel, C., Lanckman, J.-P., Luo, D., Malkova, G., Meiklejohn, I., Moskalenko, N., Oliva, M., Phillips, M., Ramos, M., Sannel, A. B. K., Sergeev, D., Seybold, C., Skryabin, P., Vasiliev, A., Wu, Q., Yoshikawa, K., Zheleznyak, M., and Lantuit, H.: Permafrost is warming at a global scale, Nat. Commun., 10, 264, https://doi.org/10.1038/s41467-018-08240-4, 2019.
Borge, A. F., Westermann, S., Solheim, I., and Etzelmüller, B.: Strong degradation of palsas and peat plateaus in northern Norway during the last 60 years, The Cryosphere, 11, 1–16, https://doi.org/10.5194/tc-11-1-2017, 2017.
Christiansen, H. H., Etzelmuller, B., Isaksen, K., Juliussen, H., Farbrot, H., Humlum, O., Johansson, M., Ingeman-Nielsen, T., Kristensen, L., Hjort, J., Holmlund, P., Sannel, A. B. K., Sigsgaard, C., Akerman, H. J., Foged, N., Blikra, L. H., Pernosky, M. A., and Ødegård, R. S.: The Thermal State of Permafrost in the Nordic Area during the International Polar Year 2007-2009, Permafrost Periglac., 21, 156–181, https://doi.org/10.1002/ppp.687, 2010.
Crochet, P. and Jóhannesson, T.: A data set of gridded daily temperature in Iceland, 1949–2010, Jökull, 61, 1–17, https://www.vedur.is/media/vedurstofan/utgafa/hlidarefni/J61-CrochetJohannesson.pdf (last access: 13 December 2023), 2011.
Czekirda, J., Westermann, S., Etzelmüller, B., and Jóhannesson, T.: Transient modelling of permafrost distribution in Iceland, Front. Earth Sci., 7, 130, https://doi.org/10.3389/feart.2019.00130, 2019.
Dyrrdal, A. V., Saloranta, T., Skaugen, T., and Stranden, H. B.: Changes in snow depth in Norway during the period 1961–2010, J. Hydrology Research, 44, 169–179, https://doi.org/10.2166/nh.2012.064, 2012.
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Short summary
Permafrost (permanently frozen ground) is widespread in the mountains of Norway and Iceland. Several boreholes were drilled after 1999 for long-term permafrost monitoring. We document a strong warming of permafrost, including the development of unfrozen bodies in the permafrost. Warming and degradation of mountain permafrost may lead to more natural hazards.
Permafrost (permanently frozen ground) is widespread in the mountains of Norway and Iceland....
