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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Liss Marie Andreassen, Ketil Isaksen, Lukas J. Monrad-Krohn, Jogscha M. Abderhalden, Luc Girod, Jessica De Marco, Bernd Etzelmüller, Simon Oldani, and Rune Strand Ødegård
EGUsphere, https://doi.org/10.5194/egusphere-2026-3152, https://doi.org/10.5194/egusphere-2026-3152, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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Juvfonne is a small ice patch and contains the oldest ice dated in Norway so far. Juvfonne prevails due to drifting snow and can fill up after years with surface lowering. However, the reduction in area and volume over the period 2010–2025 reveal that Juvfonne is vulnerable to the current warming. Ice thickness measurements conducted in September 2025 reveal a current maximum thickness of less than 9 meters and an interpolated mean thickness of < 3 meters.
Andreas Aspaas, Gregory Bievre, Pascal Lacroix, Nadège Langet, Juditha Aga, Ingrid Skrede, Lene Kristensen, Bernd Etzelmuller, and François Renard
EGUsphere, https://doi.org/10.5194/egusphere-2026-62, https://doi.org/10.5194/egusphere-2026-62, 2026
Short summary
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Climate change increases landslide risk in cold regions. We analyzed 12 years of GPS, borehole, water, and seismic data from two landslides in Arctic Norway, one with permafrost and one without. Both accelerate in spring and autumn due to water infiltration. One slip zone shows increasing snowmelt sensitivity while seismic data reveal seasonal stiffness changes. Results advance understanding of water-driven landslide dynamics in Arctic climates.
Alexandru Onaca, Flavius Sîrbu, Valentin Poncoş, Christin Hilbich, Tazio Strozzi, Petru Urdea, Răzvan Popescu, Oana Berzescu, Bernd Etzelmüller, Alfred Vespremeanu-Stroe, Mirela Vasile, Delia Teleagă, Dan Birtaş, Iosif Lopătiţă, Simon Filhol, Alexandru Hegyi, and Florina Ardelean
Earth Surf. Dynam., 13, 981–1001, https://doi.org/10.5194/esurf-13-981-2025, https://doi.org/10.5194/esurf-13-981-2025, 2025
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This study establishes a methodology for the study of slow-moving rock glaciers in marginal permafrost and provides the basic knowledge for understanding rock glaciers in South East Europe. By using a combination of different methods (remote sensing, geophysical survey, thermal measurements), we found out that, on the transitional rock glaciers, low ground ice content (i.e. below 20 %) produces horizontal displacements of up to 3 cm per year.
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.
Liss Marie Andreassen, Ketil Isaksen, Lukas J. Monrad-Krohn, Jogscha M. Abderhalden, Luc Girod, Jessica De Marco, Bernd Etzelmüller, Simon Oldani, and Rune Strand Ødegård
EGUsphere, https://doi.org/10.5194/egusphere-2026-3152, https://doi.org/10.5194/egusphere-2026-3152, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
Short summary
Short summary
Juvfonne is a small ice patch and contains the oldest ice dated in Norway so far. Juvfonne prevails due to drifting snow and can fill up after years with surface lowering. However, the reduction in area and volume over the period 2010–2025 reveal that Juvfonne is vulnerable to the current warming. Ice thickness measurements conducted in September 2025 reveal a current maximum thickness of less than 9 meters and an interpolated mean thickness of < 3 meters.
Joana Baptista, Sebastian Westermann, and Gonçalo Vieira
EGUsphere, https://doi.org/10.5194/egusphere-2026-1914, https://doi.org/10.5194/egusphere-2026-1914, 2026
This preprint is open for discussion and under review for The Cryosphere (TC).
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Permafrost underlies most ice-free areas of the Antarctic Peninsula being crucial for ecosystems. Yet its response to climate warming is uncertain. Using the CryoGrid Community Model at five PERMANTAR observatories, we simulated past and future permafrost evolution. Results revealed a warming of 0.22 °C dec⁻¹ since 1950–2020 and a progressive degradation under all CMIP6 scenarios, with positive MAGTs at 20 m depth before 2100, driven by elevation, snow cover, and ocean–atmosphere interactions.
Ingrid Vesterdal Tjessem, Peter Horvath, Adam Eindride Naas, Rune Halvorsen, Kerstin Potthoff, Ketil Isaksen, Ole Einar Tveito, Terje Koren Berntsen, Ida Marielle Mienna, and Anders Bryn
EGUsphere, https://doi.org/10.5194/egusphere-2026-2717, https://doi.org/10.5194/egusphere-2026-2717, 2026
This preprint is open for discussion and under review for Biogeosciences (BG).
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We investigated how tree- and forest lines (TFLs) in Norway have shifted over the past 50–130 years. Using remapped field observations, we show that the uppermost forest along the boreal-alpine ecotone is advancing at an average rate exceeding 0.5 m per year. This advance is driven by climate warming and land use. Our findings highlight the complexity and variation in TFL dynamics, caused by a combination of regional variation, stochastic disturbances, and time-lags.
Esther Karin Bender, Matvey Debolskiy, Kjetil Aas, Sebastian Westermann, Fang Li, Jiawen Zhu, and Hanna Lee
EGUsphere, https://doi.org/10.5194/egusphere-2026-1039, https://doi.org/10.5194/egusphere-2026-1039, 2026
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This paper introduces a new method to represent ice-rich permafrost soils in the Community Land Model used for climate prediction. The approach includes key processes previously missing, enabling simulation of rapid thaw events from ground-ice melt. It improves representation of soil temperature, hydrology, and landscape dynamics, leading to more accurate future greenhouse-gas estimates.
Kristoffer Aalstad, Esteban Alonso-González, Norbert Pirk, Sebastian Westermann, Clarissa Willmes, and Ruitang Yang
EGUsphere, https://doi.org/10.48550/arXiv.2601.20049, https://doi.org/10.48550/arXiv.2601.20049, 2026
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AdaPBS is a new algorithm to combine observations with cryospheric numerical models. AdaPBS is an iterative algorithm that automatically adjusts computing effort to the task, allowing the implementation of early stopping strategies. We tested AdaPBS at multiple sites with different models, matching or outperforming standard methods, when compared against more complex (computationally expensive) algorithms.
Juditha Aga, Antoni G. Lewkowicz, and Sebastian Westermann
EGUsphere, https://doi.org/10.5194/egusphere-2026-916, https://doi.org/10.5194/egusphere-2026-916, 2026
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In this study, we explore the influence of a warming climate on landslides in ice-rich permafrost slopes. Using climate, terrain and soil data, we built a model that simulates permafrost thaw and its impact on slope stability. We tested the model on Banks Island, Canada, and it reproduced years with many new landslide observations and identified the most susceptible slopes. The model can also be applied to other permafrost regions, and to both past and future climate conditions.
Anfisa Pismeniuk, Peter Dörsch, Mats Ippach, Clarissa Willmes, Sunniva Sheffield, Norbert Pirk, and Sebastian Westermann
Biogeosciences, 23, 1497–1514, https://doi.org/10.5194/bg-23-1497-2026, https://doi.org/10.5194/bg-23-1497-2026, 2026
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Thermokarst ponds in high latitudes are important methane (CH4) sources in summer. Meanwhile, these ponds are ice-covered for around 60 % of the year and can accumulate CH4 in the ice and within the underlying water column, which potentially results in high emissions during the ice-off. Here, we present data on wintertime CH4 storage of ponds located within two peat plateaus in Northern Norway. Our results show that the wintertime CH4 storage can contribute up to 40 % to the annual CH4 budget.
Lotte Wendt, Line Rouyet, Hanne H. Christiansen, Tom Rune Lauknes, and Sebastian Westermann
The Cryosphere, 20, 1179–1197, https://doi.org/10.5194/tc-20-1179-2026, https://doi.org/10.5194/tc-20-1179-2026, 2026
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In permafrost environments, the ground surface moves due to the formation and melt of ice in the ground. This study compares ground surface displacements measured from satellite images against field data of ground ice contents. We find good agreement between the detected seasonal subsidence and observed ground ice melt. Our results show the potential of satellite remote sensing for mapping ground ice variability, but also indicate that ice in excess of the pore space must be considered.
Robin B. Zweigel, Dashtseren Avirmed, Khurelbaatar Temuujin, Clare Webster, Hanna Lee, and Sebastian Westermann
The Cryosphere, 20, 1001–1023, https://doi.org/10.5194/tc-20-1001-2026, https://doi.org/10.5194/tc-20-1001-2026, 2026
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Two years of data along a forest disturbance gradient in Mongolia show a larger annual ground surface temperature range in dead and logged forests than intact forest, while the range is dampened in stands of young regrowth. Compared to intact forest, mean annual ground surface temperatures are 0.5 °C colder in dead and logged forest and dense stands of young regrowth. This is linked to differences in vegetation and surface cover due to the disturbance and patterns in livestock activity.
Andreas Aspaas, Gregory Bievre, Pascal Lacroix, Nadège Langet, Juditha Aga, Ingrid Skrede, Lene Kristensen, Bernd Etzelmuller, and François Renard
EGUsphere, https://doi.org/10.5194/egusphere-2026-62, https://doi.org/10.5194/egusphere-2026-62, 2026
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Climate change increases landslide risk in cold regions. We analyzed 12 years of GPS, borehole, water, and seismic data from two landslides in Arctic Norway, one with permafrost and one without. Both accelerate in spring and autumn due to water infiltration. One slip zone shows increasing snowmelt sensitivity while seismic data reveal seasonal stiffness changes. Results advance understanding of water-driven landslide dynamics in Arctic climates.
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
The Cryosphere, 19, 6591–6628, https://doi.org/10.5194/tc-19-6591-2025, https://doi.org/10.5194/tc-19-6591-2025, 2025
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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.
Anna-Maria Virkkala, Isabel Wargowsky, Judith Vogt, McKenzie A. Kuhn, Simran Madaan, Richard O'Keefe, Tiffany Windholz, Kyle A. Arndt, Brendan M. Rogers, Jennifer D. Watts, Kelcy Kent, Mathias Göckede, David Olefeldt, Gerard Rocher-Ros, Edward A. G. Schuur, David Bastviken, Kristoffer Aalstad, Kelly Aho, Joonatan Ala-Könni, Haley Alcock, Inge Althuizen, Christopher D. Arp, Jun Asanuma, Katrin Attermeyer, Mika Aurela, Sivakiruthika Balathandayuthabani, Alan Barr, Maialen Barret, Ochirbat Batkhishig, Christina Biasi, Mats P. Björkman, Andrew Black, Elena Blanc-Betes, Pascal Bodmer, Julia Boike, Abdullah Bolek, Frédéric Bouchard, Ingeborg Bussmann, Lea Cabrol, Eleonora Canfora, Sean Carey, Karel Castro-Morales, Namyi Chae, Andres Christen, Torben R. Christensen, Casper T. Christiansen, Housen Chu, Graham Clark, Francois Clayer, Patrick Crill, Christopher Cunada, Scott J. Davidson, Joshua F. Dean, Sigrid Dengel, Matteo Detto, Catherine Dieleman, Florent Domine, Egor Dyukarev, Colin Edgar, Bo Elberling, Craig A. Emmerton, Eugenie Euskirchen, Grant Falvo, Thomas Friborg, Michelle Garneau, Mariasilvia Giamberini, Mikhail V. Glagolev, Miquel A. Gonzalez-Meler, Gustaf Granath, Jón Guðmundsson, Konsta Happonen, Yoshinobu Harazono, Lorna Harris, Josh Hashemi, Nicholas Hasson, Janna Heerah, Liam Heffernan, Manuel Helbig, Warren Helgason, Michal Heliasz, Greg Henry, Geert Hensgens, Tetsuya Hiyama, Macall Hock, David Holl, Beth Holmes, Jutta Holst, Thomas Holst, Gabriel Hould-Gosselin, Elyn Humphreys, Jacqueline Hung, Jussi Huotari, Hiroki Ikawa, Danil V. Ilyasov, Mamoru Ishikawa, Go Iwahana, Hiroki Iwata, Marcin Antoni Jackowicz-Korczynski, Joachim Jansen, Järvi Järveoja, Vincent E. J. Jassey, Rasmus Jensen, Katharina Jentzsch, Robert G. Jespersen, Carl-Fredrik Johannesson, Chersity P. Jones, Anders Jonsson, Ji Young Jung, Sari Juutinen, Evan Kane, Jan Karlsson, Sergey Karsanaev, Kuno Kasak, Julia Kelly, Kasha Kempton, Marcus Klaus, George W. Kling, Natacha Kljun, Jacqueline Knutson, Hideki Kobayashi, John Kochendorfer, Kukka-Maaria Kohonen, Pasi Kolari, Mika Korkiakoski, Aino Korrensalo, Pirkko Kortelainen, Egle Koster, Kajar Koster, Ayumi Kotani, Praveena Krishnan, Juliya Kurbatova, Lars Kutzbach, Min Jung Kwon, Ethan D. Kyzivat, Jessica Lagroix, Theodore Langhorst, Elena Lapshina, Tuula Larmola, Klaus S. Larsen, Isabelle Laurion, Justin Ledman, Hanna Lee, A. Joshua Leffler, Lance Lesack, Anders Lindroth, David Lipson, Annalea Lohila, Efrén López-Blanco, Vincent L. St. Louis, Erik Lundin, Misha Luoto, Takashi Machimura, Marta Magnani, Avni Malhotra, Marja Maljanen, Ivan Mammarella, Elisa Männistö, Luca Belelli Marchesini, Phil Marsh, Pertti J. Martkainen, Maija E. Marushchak, Mikhail Mastepanov, Alex Mavrovic, Trofim Maximov, Christina Minions, Marco Montemayor, Tomoaki Morishita, Patrick Murphy, Daniel F. Nadeau, Erin Nicholls, Mats B. Nilsson, Anastasia Niyazova, Jenni Nordén, Koffi Dodji Noumonvi, Hannu Nykanen, Walter Oechel, Anne Ojala, Tomohiro Okadera, Sujan Pal, Alexey V. Panov, Tim Papakyriakou, Dario Papale, Sang-Jong Park, Frans-Jan W. Parmentier, Gilberto Pastorello, Mike Peacock, Matthias Peichl, Roman Petrov, Kyra St. Pierre, Norbert Pirk, Jessica Plein, Vilmantas Preskienis, Anatoly Prokushkin, Jukka Pumpanen, Hilary A. Rains, Niklas Rakos, Aleski Räsänen, Helena Rautakoski, Riika Rinnan, Janne Rinne, Adrian Rocha, Nigel Roulet, Alexandre Roy, Anna Rutgersson, Aleksandr F. Sabrekov, Torsten Sachs, Erik Sahlée, Alejandro Salazar, Henrique Oliveira Sawakuchi, Christopher Schulze, Roger Seco, Armando Sepulveda-Jauregui, Svetlana Serikova, Abbey Serrone, Hanna M. Silvennoinen, Sofie Sjogersten, June Skeeter, Jo Snöälv, Sebastian Sobek, Oliver Sonnentag, Emily H. Stanley, Maria Strack, Lena Strom, Patrick Sullivan, Ryan Sullivan, Anna Sytiuk, Torbern Tagesson, Pierre Taillardat, Julie Talbot, Suzanne E. Tank, Mario Tenuta, Irina Terenteva, Frederic Thalasso, Antoine Thiboult, Halldor Thorgeirsson, Fenix Garcia Tigreros, Margaret Torn, Amy Townsend-Small, Claire Treat, Alain Tremblay, Carlo Trotta, Eeva-Stiina Tuittila, Merritt Turetsky, Masahito Ueyama, Muhammad Umair, Aki Vähä, Lona van Delden, Maarten van Hardenbroek, Andrej Varlagin, Ruth K. Varner, Elena Veretennikova, Timo Vesala, Tarmo Virtanen, Carolina Voigt, Jorien E. Vonk, Robert Wagner, Katey Walter Anthony, Qinxue Wang, Masataka Watanabe, Hailey Webb, Jeffrey M. Welker, Andreas Westergaard-Nielsen, Sebastian Westermann, Jeffrey R. White, Christian Wille, Scott N. Williamson, Scott Zolkos, Donatella Zona, and Susan M. Natali
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-585, https://doi.org/10.5194/essd-2025-585, 2025
Revised manuscript accepted for ESSD
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This dataset includes monthly measurements of carbon dioxide and methane exchange between land, water, and the atmosphere from over 1,000 sites in Arctic and boreal regions. It combines measurements from a variety of ecosystems, including wetlands, forests, tundra, lakes, and rivers, gathered by over 260 researchers from 1984–2024. This dataset can be used to improve and reduce uncertainty in carbon budgets in order to strengthen our understanding of climate feedbacks in a warming world.
Alexandru Onaca, Flavius Sîrbu, Valentin Poncoş, Christin Hilbich, Tazio Strozzi, Petru Urdea, Răzvan Popescu, Oana Berzescu, Bernd Etzelmüller, Alfred Vespremeanu-Stroe, Mirela Vasile, Delia Teleagă, Dan Birtaş, Iosif Lopătiţă, Simon Filhol, Alexandru Hegyi, and Florina Ardelean
Earth Surf. Dynam., 13, 981–1001, https://doi.org/10.5194/esurf-13-981-2025, https://doi.org/10.5194/esurf-13-981-2025, 2025
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This study establishes a methodology for the study of slow-moving rock glaciers in marginal permafrost and provides the basic knowledge for understanding rock glaciers in South East Europe. By using a combination of different methods (remote sensing, geophysical survey, thermal measurements), we found out that, on the transitional rock glaciers, low ground ice content (i.e. below 20 %) produces horizontal displacements of up to 3 cm per year.
Clarissa Willmes, Kristoffer Aalstad, and Sebastian Westermann
EGUsphere, https://doi.org/10.5194/egusphere-2025-3142, https://doi.org/10.5194/egusphere-2025-3142, 2025
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In permafrost areas, the spatial variability of the snow cover significantly affects the ground thermal regime. This study presents an algorithm that integrates satellite data into a permafrost model to enhance the spatial detail of ground temperature simulations. At a site on Svalbard, the algorithm improves simulations of ground temperatures especially for wind-blown ridges with little snow, as well as snow-drift sites.
Marco Mazzolini, Kristoffer Aalstad, Esteban Alonso-González, Sebastian Westermann, and Désirée Treichler
The Cryosphere, 19, 3831–3848, https://doi.org/10.5194/tc-19-3831-2025, https://doi.org/10.5194/tc-19-3831-2025, 2025
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In this work, we showcase the use the satellite laser altimeter ICESat-2, which is able to retrieve snow depth in areas where snow amounts are still poorly estimated despite the importance of these water resources. We can update snow models with these observations through algorithms that spatially propagate the information beyond the satellite profiles. The positive results show the potential of the approach to improve snow simulations, in terms of average snow depth and spatial distribution.
Joana Pedro Baptista, Gonçalo Brito Guapo Teles Vieira, António Manuel de Carvalho Soares Correia, Hyoungseok Lee, and Sebastian Westermann
The Cryosphere, 19, 3459–3476, https://doi.org/10.5194/tc-19-3459-2025, https://doi.org/10.5194/tc-19-3459-2025, 2025
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Permafrost underlies ice-free areas of Antarctica, but its response to long-term warming is unclear due to a limited number of monitoring sites. To address this, we used the CryoGrid model, forced with climate data, to estimate permafrost temperatures and active layer thickness at King Sejong Station since 1950. The results show ground temperatures rising 0.25 °C per decade and the active layer thickening by 2 m. Warming has accelerated since 2015, highlighting the need for continued monitoring.
Jacqueline K. Knutson, François Clayer, Peter Dörsch, Sebastian Westermann, and Heleen A. de Wit
Biogeosciences, 22, 3899–3914, https://doi.org/10.5194/bg-22-3899-2025, https://doi.org/10.5194/bg-22-3899-2025, 2025
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Thawing permafrost at Iškoras in northern Norway is transforming peat plateaus into thermokarst ponds and wetlands. These small ponds show striking oversaturation of dissolved greenhouse gases, such as carbon dioxide (CO2) and methane (CH4), partly owing to organic matter processing. Streams nearby emit CO2, driven by turbulence. As permafrost disappears, carbon dynamics will change, potentially increasing emissions of CH4. This study highlights the need to integrate these changes into climate models.
Cassandra E. M. Koenig, Christin Hilbich, Christian Hauck, Lukas U. Arenson, and Pablo Wainstein
The Cryosphere, 19, 2653–2676, https://doi.org/10.5194/tc-19-2653-2025, https://doi.org/10.5194/tc-19-2653-2025, 2025
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This study presents the first regional compilation of borehole temperature data from high-altitude permafrost sites in the Andes, providing a baseline of ground thermal conditions. Data from 53 boreholes show thermal characteristics similar to other mountain permafrost areas, but uniquely shaped by Andean topo-climatic conditions. The study emphasizes the need for ongoing monitoring and is a notable collaboration between industry, academia, and regulators in advancing climate change research.
Clemens Moser, Umberto Morra di Cella, Christian Hauck, and Adrián Flores Orozco
The Cryosphere, 19, 143–171, https://doi.org/10.5194/tc-19-143-2025, https://doi.org/10.5194/tc-19-143-2025, 2025
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We use electrical conductivity and induced polarization in an imaging framework to quantify hydrogeological parameters in the active Gran Sometta rock glacier. The results show high spatial variability in the hydrogeological parameters across the rock glacier and are validated by saltwater tracer tests coupled with 3D electrical conductivity imaging. Hydrogeological information was linked to kinematic data to further investigate its role in rock glacier movement.
Julie Wee, Sebastián Vivero, Tamara Mathys, Coline Mollaret, Christian Hauck, Christophe Lambiel, Jan Beutel, and Wilfried Haeberli
The Cryosphere, 18, 5939–5963, https://doi.org/10.5194/tc-18-5939-2024, https://doi.org/10.5194/tc-18-5939-2024, 2024
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This study highlights the importance of a multi-method and multi-disciplinary 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.
Robin Benjamin Zweigel, Avirmed Dashtseren, Khurelbaatar Temuujin, Anarmaa Sharkhuu, Clare Webster, Hanna Lee, and Sebastian Westermann
Biogeosciences, 21, 5059–5077, https://doi.org/10.5194/bg-21-5059-2024, https://doi.org/10.5194/bg-21-5059-2024, 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.
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.
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.
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.
Cited articles
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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....
