Articles | Volume 8, issue 6
https://doi.org/10.5194/tc-8-2063-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/tc-8-2063-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
14 Nov 2014
Research article |
| 14 Nov 2014
A statistical approach to represent small-scale variability of permafrost temperatures due to snow cover
K. Gisnås
Department of Geosciences, University of Oslo, Oslo, Norway
S. Westermann
Department of Geosciences, University of Oslo, Oslo, Norway
Center for Permafrost, Department of Geography and Geology, University of Copenhagen, Copenhagen, Denmark
T. V. Schuler
Department of Geosciences, University of Oslo, Oslo, Norway
T. Litherland
Department of Geosciences, University of Oslo, Oslo, Norway
K. Isaksen
Norwegian Meteorological Institute, Oslo, Norway
J. Boike
Alfred Wegener Institute, Potsdam, Germany
B. Etzelmüller
Department of Geosciences, University of Oslo, Oslo, Norway
Related authors
Rosa M. Palau, Kjersti Gleditsch Gisnås, Anders Solheim, and Graham Lewis Gilbert
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhess-2024-46, https://doi.org/10.5194/nhess-2024-46, 2024
Revised manuscript has not been submitted
Short summary
Short summary
This paper looks at the relationship between rockfalls and weather conditions in two regions of Norway. The study explores how often rockfalls occur and how this might change in the future due to climate change. The results indicate that changes in temperature, rather than just heavy rain or snow melt, can have a big impact on the time rockfalls happen. In particular, when temperatures oscillate up and down, rockfalls are observed more often.
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
Short summary
Short summary
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, 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
Short summary
Short summary
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, 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
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Coline Bouchayer, Ugo Nanni, Pierre-Marie Lefeuvre, John Hult, Louise Steffensen Schmidt, Jack Kohler, François Renard, and Thomas V. Schuler
The Cryosphere, 18, 2939–2968, https://doi.org/10.5194/tc-18-2939-2024, https://doi.org/10.5194/tc-18-2939-2024, 2024
Short summary
Short summary
We explore the interplay between surface runoff and subglacial conditions. We focus on Kongsvegen glacier in Svalbard. We drilled 350 m down to the glacier base to measure water pressure, till strength, seismic noise, and glacier surface velocity. In the low-melt season, the drainage system adapted gradually, while the high-melt season led to a transient response, exceeding drainage capacity and enhancing sliding. Our findings contribute to discussions on subglacial hydro-mechanical processes.
Thomas J. Barnes, Thomas V. Schuler, Simon Filhol, and Karianne S. Lilleøren
Earth Surf. Dynam., 12, 801–818, https://doi.org/10.5194/esurf-12-801-2024, https://doi.org/10.5194/esurf-12-801-2024, 2024
Short summary
Short summary
In this paper, we use machine learning to automatically outline landforms based on their characteristics. We test several methods to identify the most accurate and then proceed to develop the most accurate to improve its accuracy further. We manage to outline landforms with 65 %–75 % accuracy, at a resolution of 10 m, thanks to high-quality/high-resolution elevation data. We find that it is possible to run this method at a country scale to quickly produce landform inventories for future studies.
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
Short summary
Short summary
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.
Rosa M. Palau, Kjersti Gleditsch Gisnås, Anders Solheim, and Graham Lewis Gilbert
Nat. Hazards Earth Syst. Sci. Discuss., https://doi.org/10.5194/nhess-2024-46, https://doi.org/10.5194/nhess-2024-46, 2024
Revised manuscript has not been submitted
Short summary
Short summary
This paper looks at the relationship between rockfalls and weather conditions in two regions of Norway. The study explores how often rockfalls occur and how this might change in the future due to climate change. The results indicate that changes in temperature, rather than just heavy rain or snow melt, can have a big impact on the time rockfalls happen. In particular, when temperatures oscillate up and down, rockfalls are observed more often.
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
Short summary
Short summary
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.
Andrea Spolaor, Federico Scoto, Catherine Larose, Elena Barbaro, Francois Burgay, Mats P. Bjorkman, David Cappelletti, Federico Dallo, Fabrizio de Blasi, Dmitry Divine, Giuliano Dreossi, Jacopo Gabrieli, Elisabeth Isaksson, Jack Kohler, Tonu Martma, Louise S. Schmidt, Thomas V. Schuler, Barbara Stenni, Clara Turetta, Bartłomiej Luks, Mathieu Casado, and Jean-Charles Gallet
The Cryosphere, 18, 307–320, https://doi.org/10.5194/tc-18-307-2024, https://doi.org/10.5194/tc-18-307-2024, 2024
Short summary
Short summary
We evaluate the impact of the increased snowmelt on the preservation of the oxygen isotope (δ18O) signal in firn records recovered from the top of the Holtedahlfonna ice field located in the Svalbard archipelago. Thanks to a multidisciplinary approach we demonstrate a progressive deterioration of the isotope signal in the firn core. We link the degradation of the δ18O signal to the increased occurrence and intensity of melt events associated with the rapid warming occurring in the archipelago.
Bernd Etzelmüller, Ketil Isaksen, Justyna Czekirda, Sebastian Westermann, Christin Hilbich, and Christian Hauck
The Cryosphere, 17, 5477–5497, https://doi.org/10.5194/tc-17-5477-2023, https://doi.org/10.5194/tc-17-5477-2023, 2023
Short summary
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.
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
Short summary
Short summary
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
Preprint archived
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Anirudha Mahagaonkar, Geir Moholdt, and Thomas V. Schuler
The Cryosphere Discuss., https://doi.org/10.5194/tc-2023-4, https://doi.org/10.5194/tc-2023-4, 2023
Revised manuscript not accepted
Short summary
Short summary
Surface meltwater lakes along the margins of the Antarctic Ice Sheet can be important for ice shelf dynamics and stability. We used optical satellite imagery to study seasonal evolution of meltwater lakes in Dronning Maud Land. We found large interannual variability in lake extents, but with consistent seasonal patterns. Although correlation with summer air temperature was strong locally, other climatic and environmental factors need to be considered to explain the large regional variability.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Chloé Scholzen, Thomas V. Schuler, and Adrien Gilbert
The Cryosphere, 15, 2719–2738, https://doi.org/10.5194/tc-15-2719-2021, https://doi.org/10.5194/tc-15-2719-2021, 2021
Short summary
Short summary
We use a two-dimensional model of water flow below the glaciers in Kongsfjord, Svalbard, to investigate how different processes of surface-to-bed meltwater transfer affect subglacial hydraulic conditions. The latter are important for the sliding motion of glaciers, which in some cases exhibit huge variations. Our findings indicate that the glaciers in our study area undergo substantial sliding because water is poorly evacuated from their base, with limited influence from the surface hydrology.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Elena Barbaro, Krystyna Koziol, Mats P. Björkman, Carmen P. Vega, Christian Zdanowicz, Tonu Martma, Jean-Charles Gallet, Daniel Kępski, Catherine Larose, Bartłomiej Luks, Florian Tolle, Thomas V. Schuler, Aleksander Uszczyk, and Andrea Spolaor
Atmos. Chem. Phys., 21, 3163–3180, https://doi.org/10.5194/acp-21-3163-2021, https://doi.org/10.5194/acp-21-3163-2021, 2021
Short summary
Short summary
This paper shows the most comprehensive seasonal snow chemistry survey to date, carried out in April 2016 across 22 sites on 7 glaciers across Svalbard. The dataset consists of the concentration, mass loading, spatial and altitudinal distribution of major ion species (Ca2+, K+,
Na2+, Mg2+,
NH4+, SO42−,
Br−, Cl− and
NO3−), together with its stable oxygen and hydrogen isotope composition (δ18O and
δ2H) in the snowpack. This study was part of the larger Community Coordinated Snow Study in Svalbard.
Christian Zdanowicz, Jean-Charles Gallet, Mats P. Björkman, Catherine Larose, Thomas Schuler, Bartłomiej Luks, Krystyna Koziol, Andrea Spolaor, Elena Barbaro, Tõnu Martma, Ward van Pelt, Ulla Wideqvist, and Johan Ström
Atmos. Chem. Phys., 21, 3035–3057, https://doi.org/10.5194/acp-21-3035-2021, https://doi.org/10.5194/acp-21-3035-2021, 2021
Short summary
Short summary
Black carbon (BC) aerosols are soot-like particles which, when transported to the Arctic, darken snow surfaces, thus indirectly affecting climate. Information on BC in Arctic snow is needed to measure their impact and monitor the efficacy of pollution-reduction policies. This paper presents a large new set of BC measurements in snow in Svalbard collected between 2007 and 2018. It describes how BC in snow varies across the archipelago and explores some factors controlling these variations.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Andreas Alexander, Jaroslav Obu, Thomas V. Schuler, Andreas Kääb, and Hanne H. Christiansen
The Cryosphere, 14, 4217–4231, https://doi.org/10.5194/tc-14-4217-2020, https://doi.org/10.5194/tc-14-4217-2020, 2020
Short summary
Short summary
In this study we present subglacial air, ice and sediment temperatures from within the basal drainage systems of two cold-based glaciers on Svalbard during late spring and the summer melt season. We put the data into the context of air temperature and rainfall at the glacier surface and show the importance of surface events on the subglacial thermal regime and erosion around basal drainage channels. Observed vertical erosion rates thereby reachup to 0.9 m d−1.
Aynom T. Teweldebrhan, Thomas V. Schuler, John F. Burkhart, and Morten Hjorth-Jensen
Hydrol. Earth Syst. Sci., 24, 4641–4658, https://doi.org/10.5194/hess-24-4641-2020, https://doi.org/10.5194/hess-24-4641-2020, 2020
Ankit Pramanik, Jack Kohler, Katrin Lindbäck, Penelope How, Ward Van Pelt, Glen Liston, and Thomas V. Schuler
The Cryosphere Discuss., https://doi.org/10.5194/tc-2020-197, https://doi.org/10.5194/tc-2020-197, 2020
Revised manuscript not accepted
Short summary
Short summary
Freshwater discharge from tidewater glaciers influences fjord circulation and fjord ecosystem. Glacier hydrology plays crucial role in transporting water underneath glacier ice. We investigated hydrology beneath the tidewater glaciers of Kongsfjord basin in Northwest Svalbard and found that subglacial water flow differs substantially from surface flow of glacier ice. Furthermore, we derived freshwater discharge time-series from all the glaciers to the fjord.
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
Short summary
Short summary
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.
Thomas Vikhamar Schuler and Torbjørn Ims Østby
Earth Syst. Sci. Data, 12, 875–885, https://doi.org/10.5194/essd-12-875-2020, https://doi.org/10.5194/essd-12-875-2020, 2020
Short summary
Short summary
Atmospheric variables needed to force terrestrial process models (permafrost, glacier mass balance, seasonal snow, surface energy balance) have been downscaled from the ERA-40 and ERA-Interim reanalyses using methodology described in the accompanying paper. The gridded dataset has a horizontal resolution of 1 km and covers the entire Svalbard archipelago. The data have a temporal resolution of 6 h and cover the entire ERA-40 period (1957–2002) and the ERA-Interim period (1979–2017).
Andreas Alexander, Maarja Kruusmaa, Jeffrey A. Tuhtan, Andrew J. Hodson, Thomas V. Schuler, and Andreas Kääb
The Cryosphere, 14, 1009–1023, https://doi.org/10.5194/tc-14-1009-2020, https://doi.org/10.5194/tc-14-1009-2020, 2020
Short summary
Short summary
This work shows the potential of pressure and inertia sensing drifters to measure flow parameters along glacial channels. The technology allows us to record the spatial distribution of water pressures, as well as an estimation of the flow velocity along the flow path in the channels. The measurements show a high repeatability and the potential to identify channel morphology from sensor readings.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Preprint withdrawn
Short summary
Short summary
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.
Ward van Pelt, Veijo Pohjola, Rickard Pettersson, Sergey Marchenko, Jack Kohler, Bartłomiej Luks, Jon Ove Hagen, Thomas V. Schuler, Thorben Dunse, Brice Noël, and Carleen Reijmer
The Cryosphere, 13, 2259–2280, https://doi.org/10.5194/tc-13-2259-2019, https://doi.org/10.5194/tc-13-2259-2019, 2019
Short summary
Short summary
The climate in Svalbard is undergoing amplified change compared to the global mean, which has a strong impact on the climatic mass balance of glaciers and the state of seasonal snow in land areas. In this study we analyze a coupled energy balance–subsurface model dataset, which provides detailed information on distributed climatic mass balance, snow conditions, and runoff across Svalbard between 1957 and 2018.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Aynom T. Teweldebrhan, John F. Burkhart, and Thomas V. Schuler
Hydrol. Earth Syst. Sci., 22, 5021–5039, https://doi.org/10.5194/hess-22-5021-2018, https://doi.org/10.5194/hess-22-5021-2018, 2018
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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
Preprint withdrawn
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Christopher J. L. D'Amboise, Karsten Müller, Laurent Oxarango, Samuel Morin, and Thomas V. Schuler
Geosci. Model Dev., 10, 3547–3566, https://doi.org/10.5194/gmd-10-3547-2017, https://doi.org/10.5194/gmd-10-3547-2017, 2017
Short summary
Short summary
We present a new water percolation routine added to the Crocus model. The new routine is physically based, describing motion of water through a layered snowpack considering capillary-driven and gravity flow. We tested the routine on two data sets. Wet-snow layers were able to reach higher saturations than the empirical routine. Meaningful applicability is limited until new and better parameterizations of water retention are developed, and feedbacks are adjusted to handle higher saturations.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Thomas Schellenberger, Thorben Dunse, Andreas Kääb, Thomas Vikhamar Schuler, Jon Ove Hagen, and Carleen H. Reijmer
The Cryosphere Discuss., https://doi.org/10.5194/tc-2017-5, https://doi.org/10.5194/tc-2017-5, 2017
Preprint withdrawn
Short summary
Short summary
Basin-3, NE-Svalbard, was still surging with 10 m d-1 in July 2016. After a speed peak of 18.8 m d-1 in Dec 2012/Jan 2013, speed-ups are overlying the fast flow every summer. The glacier is massively calving icebergs (5.2 Gt yr-1 ~ 2 L drinking water for every human being daily!) which in the same order of magnitude as all other Svalbard glaciers together.
Since autumn 2015 also Basin-2 is surging with maximum velocities of 8.7 m d-1, an advance of more than 2 km and a mass loss of 0.7 Gt yr-1.
Torbjørn Ims Østby, Thomas Vikhamar Schuler, Jon Ove Hagen, Regine Hock, Jack Kohler, and Carleen H. Reijmer
The Cryosphere, 11, 191–215, https://doi.org/10.5194/tc-11-191-2017, https://doi.org/10.5194/tc-11-191-2017, 2017
Short summary
Short summary
We present modelled climatic mass balance for all glaciers in Svalbard for the period 1957–2014 at 1 km resolution using a coupled surface energy balance and snowpack model, thereby closing temporal and spatial gaps in direct and geodetic mass balance estimates.
Supporting previous studies, our results indicate increased mass loss over the period.
A detailed analysis of the involved energy fluxes reveals that increased mass loss is caused by atmospheric warming further amplified by feedbacks.
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Kjetil S. Aas, Thorben Dunse, Emily Collier, Thomas V. Schuler, Terje K. Berntsen, Jack Kohler, and Bartłomiej Luks
The Cryosphere, 10, 1089–1104, https://doi.org/10.5194/tc-10-1089-2016, https://doi.org/10.5194/tc-10-1089-2016, 2016
Short summary
Short summary
A high-resolution, coupled atmosphere--climatic mass balance (CMB) model is applied to Svalbard for the period 2003 to 2013. The mean CMB during this period is negative but displays large spatial and temporal variations. Comparison with observations on different scales shows a good overall model performance except for one particular glacier, where wind strongly affects the spatial patterns of CMB. The model also shows considerable sensitivity to model resolution, especially on local scales.
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
Short summary
Short summary
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.
L. Gray, D. Burgess, L. Copland, M. N. Demuth, T. Dunse, K. Langley, and T. V. Schuler
The Cryosphere, 9, 1895–1913, https://doi.org/10.5194/tc-9-1895-2015, https://doi.org/10.5194/tc-9-1895-2015, 2015
Short summary
Short summary
We show that the Cryosat (CS) radar altimeter can measure elevation change on a variety of Arctic ice caps. With the frequent coverage of Cryosat it is even possible to track summer surface height loss due to extensive melt; no other satellite altimeter has been able to do this. However, we also show that under cold conditions there is a bias between the surface and Cryosat detected elevation which varies with the conditions of the upper snow and firn layers.
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
Short summary
Short summary
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
Short summary
Short summary
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.
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
Short summary
Short summary
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
Short summary
Short summary
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.
T. Dunse, T. Schellenberger, J. O. Hagen, A. Kääb, T. V. Schuler, and C. H. Reijmer
The Cryosphere, 9, 197–215, https://doi.org/10.5194/tc-9-197-2015, https://doi.org/10.5194/tc-9-197-2015, 2015
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
M. Engelhardt, T. V. Schuler, and L. M. Andreassen
Hydrol. Earth Syst. Sci., 18, 511–523, https://doi.org/10.5194/hess-18-511-2014, https://doi.org/10.5194/hess-18-511-2014, 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
Related subject area
Frozen Ground
Effect of surficial geology mapping scale on modelled ground ice in Canadian Shield terrain
Spectral Induced Polarization survey for the estimation of hydrogeological parameters in an active rock glacier
InSAR-measured permafrost degradation of palsa peatlands in northern Sweden
The evolution of Arctic permafrost over the last 3 centuries from ensemble simulations with the CryoGridLite permafrost model
Permafrost saline water and Early to mid-Holocene permafrost aggradation in Svalbard
Environmental spaces for palsas and peat plateaus are disappearing at a circumpolar scale
Post-Little Ice Age rock wall permafrost evolution in Norway
Modelling rock glacier ice content based on InSAR-derived velocity, Khumbu and Lhotse valleys, Nepal
The temperature-dependent shear strength of ice-filled joints in rock mass considering the effect of joint roughness, opening and shear rates
Significant underestimation of peatland permafrost along the Labrador Sea coastline in northern Canada
Estimation of stream water components and residence time in a permafrost catchment in the central Tibetan Plateau using long-term water stable isotopic data
Brief communication: Improving ERA5-Land soil temperature in permafrost regions using an optimized multi-layer snow scheme
Towards accurate quantification of ice content in permafrost of the Central Andes – Part 2: An upscaling strategy of geophysical measurements to the catchment scale at two study sites
Long-term analysis of cryoseismic events and associated ground thermal stress in Adventdalen, Svalbard
Seismic physics-based characterization of permafrost sites using surface waves
Three in one: GPS-IR measurements of ground surface elevation changes, soil moisture, and snow depth at a permafrost site in the northeastern Qinghai–Tibet Plateau
Surface temperatures and their influence on the permafrost thermal regime in high-Arctic rock walls on Svalbard
Consequences of permafrost degradation for Arctic infrastructure – bridging the model gap between regional and engineering scales
Passive seismic recording of cryoseisms in Adventdalen, Svalbard
Projecting circum-Arctic excess-ground-ice melt with a sub-grid representation in the Community Land Model
Ground ice, organic carbon and soluble cations in tundra permafrost soils and sediments near a Laurentide ice divide in the Slave Geological Province, Northwest Territories, Canada
The ERA5-Land soil temperature bias in permafrost regions
Brief Communication: The reliability of gas extraction techniques for analysing CH4 and N2O compositions in gas trapped in permafrost ice wedges
Geochemical signatures of pingo ice and its origin in Grøndalen, west Spitsbergen
Mountain permafrost degradation documented through a network of permanent electrical resistivity tomography sites
Permafrost variability over the Northern Hemisphere based on the MERRA-2 reanalysis
Distinguishing ice-rich and ice-poor permafrost to map ground temperatures and ground ice occurrence in the Swiss Alps
New ground ice maps for Canada using a paleogeographic modelling approach
Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada)
Characteristics and fate of isolated permafrost patches in coastal Labrador, Canada
Rock glaciers in Daxue Shan, south-eastern Tibetan Plateau: an inventory, their distribution, and their environmental controls
Microtopographic control on the ground thermal regime in ice wedge polygons
Change in frozen soils and its effect on regional hydrology, upper Heihe basin, northeastern Qinghai–Tibetan Plateau
Climate warming over the past half century has led to thermal degradation of permafrost on the Qinghai–Tibet Plateau
Decadal changes of surface elevation over permafrost area estimated using reflected GPS signals
Characterizing permafrost active layer dynamics and sensitivity to landscape spatial heterogeneity in Alaska
Resolution capacity of geophysical monitoring regarding permafrost degradation induced by hydrological processes
A new map of permafrost distribution on the Tibetan Plateau
Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ2H analysis
Modelling rock wall permafrost degradation in the Mont Blanc massif from the LIA to the end of the 21st century
New observations indicate the possible presence of permafrost in North Africa (Djebel Toubkal, High Atlas, Morocco)
Transient modeling of the ground thermal conditions using satellite data in the Lena River delta, Siberia
Wind-driven snow conditions control the occurrence of contemporary marginal mountain permafrost in the Chic-Choc Mountains, south-eastern Canada: a case study from Mont Jacques-Cartier
Numerical modelling of convective heat transport by air flow in permafrost talus slopes
Cryostratigraphy, sedimentology, and the late Quaternary evolution of the Zackenberg River delta, northeast Greenland
Response of seasonal soil freeze depth to climate change across China
Soil moisture redistribution and its effect on inter-annual active layer temperature and thickness variations in a dry loess terrace in Adventdalen, Svalbard
Review article: Inferring permafrost and permafrost thaw in the mountains of the Hindu Kush Himalaya region
Strong degradation of palsas and peat plateaus in northern Norway during the last 60 years
Weichselian permafrost depth in the Netherlands: a comprehensive uncertainty and sensitivity analysis
H. Brendan O'Neill, Stephen A. Wolfe, Caroline Duchesne, and Ryan J. H. Parker
The Cryosphere, 18, 2979–2990, https://doi.org/10.5194/tc-18-2979-2024, https://doi.org/10.5194/tc-18-2979-2024, 2024
Short summary
Short summary
Maps that show ground ice in permafrost at circumpolar or hemispherical scales offer only general depictions of broad patterns in ice content. In this paper, we show that using more detailed surficial geology in a ground ice computer model significantly improves the depiction of ground ice and makes the mapping useful for assessments of the effects of permafrost thaw and for reconnaissance planning of infrastructure routing.
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
Short summary
Short summary
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.
Samuel Valman, Matthias B. Siewert, Doreen Boyd, Martha Ledger, David Gee, Betsabé de la Barreda-Bautista, Andrew Sowter, and Sofie Sjögersten
The Cryosphere, 18, 1773–1790, https://doi.org/10.5194/tc-18-1773-2024, https://doi.org/10.5194/tc-18-1773-2024, 2024
Short summary
Short summary
Climate warming is thawing permafrost that makes up palsa (frost mound) peatlands, risking ecosystem collapse and carbon release as methane. We measure this regional degradation using radar satellite technology to examine ground elevation changes and show how terrain roughness measurements can be used to estimate local permafrost damage. We find that over half of Sweden's largest palsa peatlands are degrading, with the worse impacts to the north linked to increased winter precipitation.
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
Short summary
Short summary
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.
Dotan Rotem, Vladimir Lyakhovsky, Hanne Hvidtfeldt Christiansen, Yehudit Harlavan, and Yishai Weinstein
The Cryosphere, 17, 3363–3381, https://doi.org/10.5194/tc-17-3363-2023, https://doi.org/10.5194/tc-17-3363-2023, 2023
Short summary
Short summary
Frozen saline pore water, left over from post-glacial marine ingression, was found in shallow permafrost in a Svalbard fjord valley. This suggests that freezing occurred immediately after marine regression due to isostatic rebound. We conducted top-down freezing simulations, which confirmed that with Early to mid-Holocene temperatures (e.g. −4 °C), freezing could progress down to 20–40 m within 200 years. This, in turn, could inhibit flow through the sediment, therefore preserving saline fluids.
Oona Leppiniemi, Olli Karjalainen, Juha Aalto, Miska Luoto, and Jan Hjort
The Cryosphere, 17, 3157–3176, https://doi.org/10.5194/tc-17-3157-2023, https://doi.org/10.5194/tc-17-3157-2023, 2023
Short summary
Short summary
For the first time, suitable environments for palsas and peat plateaus were modeled for the whole Northern Hemisphere. The hotspots of occurrences were in northern Europe, western Siberia, and subarctic Canada. Climate change was predicted to cause almost complete loss of the studied landforms by the late century. Our predictions filled knowledge gaps in the distribution of the landforms, and they can be utilized in estimation of the pace and impacts of the climate change over northern regions.
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
Short summary
Short summary
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.
Yan Hu, Stephan Harrison, Lin Liu, and Joanne Laura Wood
The Cryosphere, 17, 2305–2321, https://doi.org/10.5194/tc-17-2305-2023, https://doi.org/10.5194/tc-17-2305-2023, 2023
Short summary
Short summary
Rock glaciers are considered to be important freshwater reservoirs in the future climate. However, the amount of ice stored in rock glaciers is poorly quantified. Here we developed an empirical model to estimate ice content in rock the glaciers in the Khumbu and Lhotse valleys, Nepal. The modelling results confirmed the hydrological importance of rock glaciers in the study area. The developed approach shows promise in being applied to permafrost regions to assess water storage of rock glaciers.
Shibing Huang, Haowei Cai, Zekun Xin, and Gang Liu
The Cryosphere, 17, 1205–1223, https://doi.org/10.5194/tc-17-1205-2023, https://doi.org/10.5194/tc-17-1205-2023, 2023
Short summary
Short summary
In this study, the warming degradation mechanism of ice-filled joints is revealed, and the effect of temperature, normal stress, shear rate and joint opening on the shear strength of rough ice-filled joints is investigated. The shear rupture modes include shear cracking of joint ice and debonding of the ice–rock interface, which is related to the above factors. The bonding strength of the ice–rock interface is larger than the shear strength of joint ice when the temperature is below −1 ℃.
Yifeng Wang, Robert G. Way, Jordan Beer, Anika Forget, Rosamond Tutton, and Meredith C. Purcell
The Cryosphere, 17, 63–78, https://doi.org/10.5194/tc-17-63-2023, https://doi.org/10.5194/tc-17-63-2023, 2023
Short summary
Short summary
Peatland permafrost in northeastern Canada has been misrepresented by models, leading to significant underestimates of peatland permafrost and permafrost distribution along the Labrador Sea coastline. Our multi-stage, multi-mapper, consensus-based inventorying process, supported by field- and imagery-based validation efforts, identifies peatland permafrost complexes all along the coast. The highest density of complexes is found to the south of the current sporadic discontinuous permafrost limit.
Shaoyong Wang, Xiaobo He, Shichang Kang, Hui Fu, and Xiaofeng Hong
The Cryosphere, 16, 5023–5040, https://doi.org/10.5194/tc-16-5023-2022, https://doi.org/10.5194/tc-16-5023-2022, 2022
Short summary
Short summary
This study used the sine-wave exponential model and long-term water stable isotopic data to estimate water mean residence time (MRT) and its influencing factors in a high-altitude permafrost catchment (5300 m a.s.l.) in the central Tibetan Plateau (TP). MRT for stream and supra-permafrost water was estimated at 100 and 255 d, respectively. Climate and vegetation factors affected the MRT of stream and supra-permafrost water mainly by changing the thickness of the permafrost active layer.
Bin Cao, Gabriele Arduini, and Ervin Zsoter
The Cryosphere, 16, 2701–2708, https://doi.org/10.5194/tc-16-2701-2022, https://doi.org/10.5194/tc-16-2701-2022, 2022
Short summary
Short summary
We implemented a new multi-layer snow scheme in the land surface scheme of ERA5-Land with revised snow densification parameterizations. The revised HTESSEL improved the representation of soil temperature in permafrost regions compared to ERA5-Land; in particular, warm bias in winter was significantly reduced, and the resulting modeled near-surface permafrost extent was improved.
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
Short summary
Short summary
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.
Rowan Romeyn, Alfred Hanssen, and Andreas Köhler
The Cryosphere, 16, 2025–2050, https://doi.org/10.5194/tc-16-2025-2022, https://doi.org/10.5194/tc-16-2025-2022, 2022
Short summary
Short summary
We have investigated a long-term record of ground vibrations, recorded by a seismic array installed in Adventdalen, Svalbard. This record contains a large number of
frost quakes, a type of ground shaking that can be produced by cracks that form as the ground cools rapidly. We use underground temperatures measured in a nearby borehole to model forces of thermal expansion and contraction that can cause these cracks. We also use the seismic measurements to estimate where these cracks occurred.
Hongwei Liu, Pooneh Maghoul, and Ahmed Shalaby
The Cryosphere, 16, 1157–1180, https://doi.org/10.5194/tc-16-1157-2022, https://doi.org/10.5194/tc-16-1157-2022, 2022
Short summary
Short summary
The knowledge of physical and mechanical properties of permafrost and its location is critical for the management of permafrost-related geohazards. Here, we developed a hybrid inverse and multiphase poromechanical approach to quantitatively estimate the physical and mechanical properties of a permafrost site. Our study demonstrates the potential of surface wave techniques coupled with our proposed data-processing algorithm to characterize a permafrost site more accurately.
Jiahua Zhang, Lin Liu, Lei Su, and Tao Che
The Cryosphere, 15, 3021–3033, https://doi.org/10.5194/tc-15-3021-2021, https://doi.org/10.5194/tc-15-3021-2021, 2021
Short summary
Short summary
We improve the commonly used GPS-IR algorithm for estimating surface soil moisture in permafrost areas, which does not consider the bias introduced by seasonal surface vertical movement. We propose a three-in-one framework to integrate the GPS-IR observations of surface elevation changes, soil moisture, and snow depth at one site and illustrate it by using a GPS site in the Qinghai–Tibet Plateau. This study is the first to use GPS-IR to measure environmental variables in the Tibetan Plateau.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Rowan Romeyn, Alfred Hanssen, Bent Ole Ruud, Helene Meling Stemland, and Tor Arne Johansen
The Cryosphere, 15, 283–302, https://doi.org/10.5194/tc-15-283-2021, https://doi.org/10.5194/tc-15-283-2021, 2021
Short summary
Short summary
A series of unusual ground motion signatures were identified in geophone recordings at a frost polygon site in Adventdalen on Svalbard. By analysing where the ground motion originated in time and space, we are able to classify them as cryoseisms, also known as frost quakes, a ground-cracking phenomenon that occurs as a result of freezing processes. The waves travelling through the ground produced by these frost quakes also allow us to measure the structure of the permafrost in the near surface.
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
Short summary
Short summary
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.
Rupesh Subedi, Steven V. Kokelj, and Stephan Gruber
The Cryosphere, 14, 4341–4364, https://doi.org/10.5194/tc-14-4341-2020, https://doi.org/10.5194/tc-14-4341-2020, 2020
Short summary
Short summary
Permafrost beneath tundra near Lac de Gras (Northwest Territories, Canada) contains more ice and less organic carbon than shown in global compilations. Excess-ice content of 20–60 %, likely remnant Laurentide basal ice, is found in upland till. This study is based on 24 boreholes up to 10 m deep. Findings highlight geology and glacial legacy as determinants of a mosaic of permafrost characteristics with potential for thaw subsidence up to several metres in some locations.
Bin Cao, Stephan Gruber, Donghai Zheng, and Xin Li
The Cryosphere, 14, 2581–2595, https://doi.org/10.5194/tc-14-2581-2020, https://doi.org/10.5194/tc-14-2581-2020, 2020
Short summary
Short summary
This study reports that ERA5-Land (ERA5L) soil temperature bias in permafrost regions correlates with the bias in air temperature and with maximum snow height. While global reanalyses are important drivers for permafrost study, ERA5L soil data are not well suited for directly informing permafrost research decision making due to their warm bias in winter. To address this, future soil temperature products in reanalyses will require permafrost-specific alterations to their land surface models.
Ji-Woong Yang, Jinho Ahn, Go Iwahana, Sangyoung Han, Kyungmin Kim, and Alexander Fedorov
The Cryosphere, 14, 1311–1324, https://doi.org/10.5194/tc-14-1311-2020, https://doi.org/10.5194/tc-14-1311-2020, 2020
Short summary
Short summary
Thawing permafrost may lead to decomposition of soil carbon and nitrogen and emission of greenhouse gases. Thus, methane and nitrous oxide compositions in ground ice may provide information on their production mechanisms in permafrost. We test conventional wet and dry extraction methods. We find that both methods extract gas from the easily extractable parts of the ice and yield similar results for mixing ratios. However, both techniques are unable to fully extract gas from the ice.
Nikita Demidov, Sebastian Wetterich, Sergey Verkulich, Aleksey Ekaykin, Hanno Meyer, Mikhail Anisimov, Lutz Schirrmeister, Vasily Demidov, and Andrew J. Hodson
The Cryosphere, 13, 3155–3169, https://doi.org/10.5194/tc-13-3155-2019, https://doi.org/10.5194/tc-13-3155-2019, 2019
Short summary
Short summary
As Norwegian geologist Liestøl (1996) recognised,
in connection with formation of pingos there are a great many unsolved questions. Drillings and temperature measurements through the pingo mound and also through the surrounding permafrost are needed before the problems can be better understood. To shed light on pingo formation here we present the results of first drilling of pingo on Spitsbergen together with results of detailed hydrochemical and stable-isotope studies of massive-ice samples.
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
Short summary
Short summary
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.
Jing Tao, Randal D. Koster, Rolf H. Reichle, Barton A. Forman, Yuan Xue, Richard H. Chen, and Mahta Moghaddam
The Cryosphere, 13, 2087–2110, https://doi.org/10.5194/tc-13-2087-2019, https://doi.org/10.5194/tc-13-2087-2019, 2019
Short summary
Short summary
The active layer thickness (ALT) in middle-to-high northern latitudes from 1980 to 2017 was produced at 81 km2 resolution by a global land surface model (NASA's CLSM) with forcing fields from a reanalysis data set, MERRA-2. The simulated permafrost distribution and ALTs agree reasonably well with an observation-based map and in situ measurements, respectively. The accumulated above-freezing air temperature and maximum snow water equivalent explain most of the year-to-year variability of ALT.
Robert Kenner, Jeannette Noetzli, Martin Hoelzle, Hugo Raetzo, and Marcia Phillips
The Cryosphere, 13, 1925–1941, https://doi.org/10.5194/tc-13-1925-2019, https://doi.org/10.5194/tc-13-1925-2019, 2019
Short summary
Short summary
A new permafrost mapping method distinguishes between ice-poor and ice-rich permafrost. The approach was tested for the entire Swiss Alps and highlights the dominating influence of the factors elevation and solar radiation on the distribution of ice-poor permafrost. Our method enabled the indication of mean annual ground temperatures and the cartographic representation of permafrost-free belts, which are bounded above by ice-poor permafrost and below by permafrost-containing excess ice.
H. Brendan O'Neill, Stephen A. Wolfe, and Caroline Duchesne
The Cryosphere, 13, 753–773, https://doi.org/10.5194/tc-13-753-2019, https://doi.org/10.5194/tc-13-753-2019, 2019
Short summary
Short summary
In this paper, we present new models to depict ground ice in permafrost in Canada, incorporating knowledge from recent studies. The model outputs we present reproduce observed regional ground ice conditions and are generally comparable with previous mapping. However, our results are more detailed and more accurately reflect ground ice conditions in many regions. The new mapping is an important step toward understanding terrain response to permafrost degradation in Canada.
Stephanie Coulombe, Daniel Fortier, Denis Lacelle, Mikhail Kanevskiy, and Yuri Shur
The Cryosphere, 13, 97–111, https://doi.org/10.5194/tc-13-97-2019, https://doi.org/10.5194/tc-13-97-2019, 2019
Short summary
Short summary
This study provides a detailed description of relict glacier ice preserved in the permafrost of Bylot Island (Nunavut). We demonstrate that the 18O composition (-34.0 0.4 ‰) of the ice is consistent with the late Pleistocene age ice in the Barnes Ice Cap. As most of the glaciated Arctic landscapes are still strongly determined by their glacial legacy, the melting of these large ice bodies could have significant impacts on permafrost geosystem landscape dynamics and ecosystems.
Robert G. Way, Antoni G. Lewkowicz, and Yu Zhang
The Cryosphere, 12, 2667–2688, https://doi.org/10.5194/tc-12-2667-2018, https://doi.org/10.5194/tc-12-2667-2018, 2018
Short summary
Short summary
Isolated patches of permafrost in southeast Labrador are among the southernmost lowland permafrost features in Canada. Local characteristics at six sites were investigated from Cartwright, NL (~ 54° N) to Blanc-Sablon, QC (~ 51° N). Annual ground temperatures varied from −0.7 °C to −2.3 °C with permafrost thicknesses of 1.7–12 m. Ground temperatures modelled for two sites showed permafrost disappearing at the southern site by 2060 and persistence beyond 2100 at the northern site only for RCP2.6.
Zeze Ran and Gengnian Liu
The Cryosphere, 12, 2327–2340, https://doi.org/10.5194/tc-12-2327-2018, https://doi.org/10.5194/tc-12-2327-2018, 2018
Short summary
Short summary
This article provides the first rock glacier inventory of Daxue Shan, south- eastern Tibetan Plateau. This study provides important data for exploring the relation between maritime periglacial environments and the development of rock glaciers on the south-eastern Tibetan Plateau (TP). It may also highlight the characteristics typical of rock glaciers found in a maritime setting.
Charles J. Abolt, Michael H. Young, Adam L. Atchley, and Dylan R. Harp
The Cryosphere, 12, 1957–1968, https://doi.org/10.5194/tc-12-1957-2018, https://doi.org/10.5194/tc-12-1957-2018, 2018
Short summary
Short summary
We investigate the relationship between ice wedge polygon topography and near-surface ground temperature using a combination of field work and numerical modeling. We analyze a year-long record of ground temperature across a low-centered polygon, then demonstrate that lower rims and deeper troughs promote warmer conditions in the ice wedge in winter. This finding implies that ice wedge cracking and growth, which are driven by cold conditions, can be impeded by rim erosion or trough subsidence.
Bing Gao, Dawen Yang, Yue Qin, Yuhan Wang, Hongyi Li, Yanlin Zhang, and Tingjun Zhang
The Cryosphere, 12, 657–673, https://doi.org/10.5194/tc-12-657-2018, https://doi.org/10.5194/tc-12-657-2018, 2018
Short summary
Short summary
This study developed a distributed hydrological model coupled with cryospherical processes and applied it in order to simulate the long-term change of frozen ground and its effect on hydrology in the upper Heihe basin. Results showed that the permafrost area shrank by 8.8%, and the frozen depth of seasonally frozen ground decreased. Runoff in cold seasons and annual liquid soil moisture increased due to frozen soils change. Groundwater recharge was enhanced due to the degradation of permafrost.
Youhua Ran, Xin Li, and Guodong Cheng
The Cryosphere, 12, 595–608, https://doi.org/10.5194/tc-12-595-2018, https://doi.org/10.5194/tc-12-595-2018, 2018
Short summary
Short summary
Approximately 88 % of the permafrost area in the 1960s has been thermally degraded in the past half century over the Qinghai–Tibetan Plateau. The mean elevations of the very cold, cold, cool, warm, very warm, and likely thawing permafrost areas increased by 88 m, 97 m, 155 m, 185 m, 161 m, and 250 m, respectively. This degradation may lead to increases in risks to infrastructure, flood, reductions in ecosystem resilience, and positive climate feedback.
Lin Liu and Kristine M. Larson
The Cryosphere, 12, 477–489, https://doi.org/10.5194/tc-12-477-2018, https://doi.org/10.5194/tc-12-477-2018, 2018
Short summary
Short summary
We demonstrate the use of reflected GPS signals to measure elevation changes over a permafrost area in northern Alaska. For the first time, we construct a daily-sampled time series of elevation changes over 12 summers. Our results show regular thaw subsidence within each summer and a secular subsidence trend of 0.3 cm per year. This method promises a new way to utilize GPS data in cold regions for studying frozen ground consistently and sustainably over a long time.
Yonghong Yi, John S. Kimball, Richard H. Chen, Mahta Moghaddam, Rolf H. Reichle, Umakant Mishra, Donatella Zona, and Walter C. Oechel
The Cryosphere, 12, 145–161, https://doi.org/10.5194/tc-12-145-2018, https://doi.org/10.5194/tc-12-145-2018, 2018
Short summary
Short summary
An important feature of the Arctic is large spatial heterogeneity in active layer conditions. We developed a modeling framework integrating airborne longwave radar and satellite data to investigate active layer thickness (ALT) sensitivity to landscape heterogeneity in Alaska. We find uncertainty in spatial and vertical distribution of soil organic carbon is the largest factor affecting ALT accuracy. Advances in remote sensing of soil conditions will enable more accurate ALT predictions.
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
Defu Zou, Lin Zhao, Yu Sheng, Ji Chen, Guojie Hu, Tonghua Wu, Jichun Wu, Changwei Xie, Xiaodong Wu, Qiangqiang Pang, Wu Wang, Erji Du, Wangping Li, Guangyue Liu, Jing Li, Yanhui Qin, Yongping Qiao, Zhiwei Wang, Jianzong Shi, and Guodong Cheng
The Cryosphere, 11, 2527–2542, https://doi.org/10.5194/tc-11-2527-2017, https://doi.org/10.5194/tc-11-2527-2017, 2017
Short summary
Short summary
The area and distribution of permafrost on the Tibetan Plateau are unclear and controversial. This paper generated a benchmark map based on the modified remote sensing products and validated it using ground-based data sets. Compared with two existing maps, the new map performed better and showed that permafrost covered areas of 1.06 × 106 km2. The results provide more detailed information on the permafrost distribution and basic data for use in future research on the Tibetan Plateau permafrost.
Jorien E. Vonk, Tommaso Tesi, Lisa Bröder, Henry Holmstrand, Gustaf Hugelius, August Andersson, Oleg Dudarev, Igor Semiletov, and Örjan Gustafsson
The Cryosphere, 11, 1879–1895, https://doi.org/10.5194/tc-11-1879-2017, https://doi.org/10.5194/tc-11-1879-2017, 2017
Florence Magnin, Jean-Yves Josnin, Ludovic Ravanel, Julien Pergaud, Benjamin Pohl, and Philip Deline
The Cryosphere, 11, 1813–1834, https://doi.org/10.5194/tc-11-1813-2017, https://doi.org/10.5194/tc-11-1813-2017, 2017
Short summary
Short summary
Permafrost degradation in high mountain rock walls provokes destabilisation, constituting a threat for human activities. In the Mont Blanc massif, more than 700 rockfalls have been inventoried in recent years (2003, 2007–2015). Understanding permafrost evolution is thus crucial to sustain this densely populated area. This study investigates the changes in rock wall permafrost from 1850 to the recent period and possible optimistic or pessimistic evolutions during the 21st century.
Gonçalo Vieira, Carla Mora, and Ali Faleh
The Cryosphere, 11, 1691–1705, https://doi.org/10.5194/tc-11-1691-2017, https://doi.org/10.5194/tc-11-1691-2017, 2017
Short summary
Short summary
The Toubkal is the highest massif in North Africa (4167 m). Landforms and deposits above 3000 m show the effects of frost action in the present-day geomorphological dynamics, but data on ground temperatures were lacking. In this study ground surface temperature data measured across an altitudinal transect are presented and analysed for the first time. The highlight is the possible occurrence of permafrost at an elevation of 3800 m, which may be of high ecological and hydrological significance.
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
Short summary
Short summary
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.
Gautier Davesne, Daniel Fortier, Florent Domine, and James T. Gray
The Cryosphere, 11, 1351–1370, https://doi.org/10.5194/tc-11-1351-2017, https://doi.org/10.5194/tc-11-1351-2017, 2017
Short summary
Short summary
This study presents data from Mont Jacques-Cartier, the highest summit in the Appalachians of south-eastern Canada, to demonstrate that the occurrence of contemporary permafrost body is associated with a very thin and wind-packed winter snow cover which brings local azonal topo-climatic conditions on the dome-shaped summit. This study is an important preliminary step in modelling the regional spatial distribution of permafrost on the highest summits in eastern North America.
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
Short summary
Short summary
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.
Graham L. Gilbert, Stefanie Cable, Christine Thiel, Hanne H. Christiansen, and Bo Elberling
The Cryosphere, 11, 1265–1282, https://doi.org/10.5194/tc-11-1265-2017, https://doi.org/10.5194/tc-11-1265-2017, 2017
Short summary
Short summary
We reconstruct the Holocene development of the Zackenberg River delta (northeast Greenland) using a combination of sedimentology, cryostratigraphy, and geochronology. We distinguish four major depositional environments and identify three cryofacies. We apply the principles of cryostratigraphy to infer the aggradational history of permafrost. This paper contains an archive of ground ice in epigenetic permafrost in northeast Greenland.
Xiaoqing Peng, Tingjun Zhang, Oliver W. Frauenfeld, Kang Wang, Bin Cao, Xinyue Zhong, Hang Su, and Cuicui Mu
The Cryosphere, 11, 1059–1073, https://doi.org/10.5194/tc-11-1059-2017, https://doi.org/10.5194/tc-11-1059-2017, 2017
Short summary
Short summary
Previous research has paid significant attention to permafrost, e.g. active layer thickness, soil temperature, area extent, and associated degradation leading to other changes. However, less focus has been given to seasonally frozen ground and vast area extent. We combined data from more than 800 observation stations, as well as gridded data, to investigate soil freeze depth across China. The results indicate that soil freeze depth decreases with climate warming.
Carina Schuh, Andrew Frampton, and Hanne Hvidtfeldt Christiansen
The Cryosphere, 11, 635–651, https://doi.org/10.5194/tc-11-635-2017, https://doi.org/10.5194/tc-11-635-2017, 2017
Short summary
Short summary
This study investigates how soil moisture retention characteristics impact ice and moisture redistribution, heat transport and active layer thickness under permafrost conditions. This is relevant for understanding how climate change interacts with permafrost, which is important because there is much stored carbon in permafrost, which may be released to the atmosphere as permafrost degrades and may then act to further enhance climate warming.
Stephan Gruber, Renate Fleiner, Emilie Guegan, Prajjwal Panday, Marc-Olivier Schmid, Dorothea Stumm, Philippus Wester, Yinsheng Zhang, and Lin Zhao
The Cryosphere, 11, 81–99, https://doi.org/10.5194/tc-11-81-2017, https://doi.org/10.5194/tc-11-81-2017, 2017
Short summary
Short summary
We review what can be inferred about permafrost in the mountains of the Hindu Kush Himalaya region. This is important because the area of permafrost exceeds that of glaciers in this region. Climate change will produce diverse permafrost-related impacts on vegetation, water quality, geohazards, and livelihoods. To mitigate this, a better understanding of high-elevation permafrost in subtropical latitudes as well as the pathways connecting environmental change and human livelihoods, is needed.
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
Short summary
Short summary
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.
Joan Govaerts, Koen Beerten, and Johan ten Veen
The Cryosphere, 10, 2907–2922, https://doi.org/10.5194/tc-10-2907-2016, https://doi.org/10.5194/tc-10-2907-2016, 2016
Short summary
Short summary
The Rupelian Clay in the Netherlands is currently the subject of a feasibility study with respect to the storage of radioactive waste in the Netherlands (OPERA-project). Many features need to be considered in the assessment of the long-term evolution of the natural environment surrounding a geological waste disposal facility. One of these is permafrost development since it may have an impact on various components of the disposal system.
Cited articles
Andersen, L. M.: En brehydrologisk undersøkelse av Midtdalsbren, Sør-Norge, Cand. Scient. thesis, Department of Geosciences, University of Oslo, Oslo, 74 pp., 1996.
Boike, J., Roth, K., and Ippisch, O.: Seasonal snow cover on frozen ground: Energy balance calculations of a permafrost site near Ny-Ålesund, Spitsbergen, J. Geophys. Res., 108, 8163, https://doi.org/10.1029/2001JD000939, 2003.
Boike, J., Ippisch, O., Overduin, P. P., Hagedorn, B., and Roth, K.: Water, heat and solute dynamics of a mud boil, Spitsbergen, Geomorphology, 95, 61–73, https://doi.org/10.1016/j.geomorph.2006.07.033, 2008.
Bruland, O., Sand, K., and Killingtveit, A.: Snow distribution at a high arctic site at Svalbard, Nord. Hydrol., 32, 1–12, 2001.
Dunse, T., Schuler, T. V., Hagen, J. O., Eiken, T., Brandt, O., and Høgda, K. A.: Recent fluctuations in the extent of the firn area of Austfonna, Svalbard, inferred from GPR, Ann. Glaciol., 50, 155–162, https://doi.org/10.3189/172756409787769780, 2009.
eKlima: Free access to weather and climate data from the Norwegian Meteorological Institute: www.eklima.no, 2013.
Etzelmüller, B.: Recent advances in mountain permafrost research, Permafrost Periglac., 24, 99–107, https://doi.org/10.1002/ppp.1772, 2013.
Etzelmüller, B., Berthling, I., and Sollid, J. L.: The distribution of permafrost in Southern Norway; a GIS approach, Seventh International Conference on Permafrost, Proceedings, Université Lavall, Québec, PQ, Canada, 251–257, 1998.
Etzelmüller, B., Berthling, I., and Sollid, J. L.: Aspects and concepts on the geomorphological significance of Holocene permafrost in southern Norway, Geomorphology, 52, 87–104, https://doi.org/10.1016/s0169-555x(02)00250-7, 2003.
Etzelmüller, B., Farbrot, H., Gu\dhmundsson, Á., Humlum, O., Tveito, O. E., and Björnsson, H.: The regional distribution of mountain permafrost in Iceland, Permafrost Periglac., 18, 185–199, https://doi.org/10.1002/ppp.583, 2007.
Farbrot, H., Hipp, T. F., Etzelmüller, B., Isaksen, K., Ødegård, R. S., Schuler, T. V., and Humlum, O.: Air and ground temperature variations observed along elevation and continentality gradients in Southern Norway, Permafrost Periglac., 22, 343–360, https://doi.org/10.1002/ppp.733, 2011.
Førland, E. and Hanssen-Bauer, I.: Increased precipitation in the Norwegian Arctic: true or false?, Climatic Change, 46, 485–509, https://doi.org/10.1023/A:1005613304674, 2000.
Gisnås, K., Etzelmuller, B., Farbrot, H., Schuler, T. V., and Westermann, S.: CryoGRID 1.0: permafrost distribution in Norway estimated by a spatial numerical Model, Permafrost Periglac., 24, 2–19, https://doi.org/10.1002/ppp.1765, 2013.
Goodrich, L. E.: The influence of snow cover on the ground thermal regime, Can. Geotech. J., 19, 421–432, 1982.
Gruber, S. and Hoelzle, M.: Statistical modelling of mountain permafrost distribution: local calibration and incorporation of remotely sensed data, Permafrost Periglac., 12, 69–77, https://doi.org/10.1002/ppp.374, 2001.
Gruber, S., King, L., Kohl, T., Herz, T., Haeberli, W., and Hoelzle, M.: Interpretation of geothermal profiles perturbed by topography: the alpine permafrost boreholes at Stockhorn Plateau, Switzerland, Permafrost Periglac., 15, 349–357, https://doi.org/10.1002/ppp.503, 2004.
Gubler, S., Fiddes, J., Keller, M., and Gruber, S.: Scale-dependent measurement and analysis of ground surface temperature variability in alpine terrain, The Cryosphere, 5, 431–443, https://doi.org/10.5194/tc-5-431-2011, 2011.
Haeberli, W.: Die Basis-Temperatur der winterlichen Schneedecke als möglicher Indikator für die Verbreitung von Permafrost in den Alpen, Zeitschrift für Gletscherkunde und Glazialgeologie, 9, 221–227, 1973.
Hagen, J. O.: Brefrontprosesser ved Hardangerjøkulen (Midtdalsbreen, Blåisen og Brattfonn), Cand. Scient., Geography Department, University of Oslo, Oslo, 105 pp., 1978.
Harris, C., Arenson, L. U., Christiansen, H. H., Etzelmüller, B., Frauenfelder, R., Gruber, S., Haeberli, W., Hauck, C., Hölzle, M., Humlum, O., Isaksen, K., Kääb, A., Lehning, M., Lütschg, M. A., Matsuoka, N., Murton, J., Nötzli, J., Phillips, M., Ross, N., Seppälä, M., Springman, S., and Vonder Muhll, D.: Permafrost and climate in Europe: monitoring and modelling thermal, geomorphological and geotechnical responses, Earth-Sci. Rev., 92, 117–171, 2009.
Hauck, C., Isaksen, K., Mühll, D. V., and Sollid, J. L.: Geophysical surveys designed to delineate the altitudinal limit of mountain permafrost: an example from Jotunheimen, Norway, Permafrost Periglac., 15, 191–205, https://doi.org/10.1002/ppp.493, 2004.
Hipp, T., Etzelmüller, B., Farbrot, H., Schuler, T. V., and Westermann, S.: Modelling borehole temperatures in Southern Norway – insights into permafrost dynamics during the 20th and 21st century, The Cryosphere, 6, 553–571, https://doi.org/10.5194/tc-6-553-2012, 2012.
Isaksen, K., Holmlund, P., Sollid, J., and Harris, C.: Three deep alpine-permafrost boreholes in Svalbard and Scandinavia, Permafrost Periglac., 12, 13–25, https://doi.org/10.1002/ppp.380, 2001.
Isaksen, K., Hauck, C., Gudevang, E., Ødegård, R. S., and Sollid, J. L.: Mountain permafrost distribution in Dovrefjell and Jotunheimen, southern Norway, based on BTS and DC resistivity tomography data, Norsk Geogr. Tidsskr., 56, 122–136, https://doi.org/10.1080/002919502760056459, 2002.
Isaksen, K., Heggem, E., Bakkehøi, S., Ødegård, R., Eiken, T., Etzelmüller, B., and Sollid, J.: Mountain permafrost and energy balance on Juvvasshøe, southern Norway, Eight International Conference on Permafrost, Zurich, Switzerland, 467–472, 2003.
Isaksen, K., Sollid, J. L., Holmlund, P., and Harris, C.: Recent warming of mountain permafrost in Svalbard and Scandinavia, J. Geophys. Res., 112, F02S04, https://doi.org/10.1029/2006jf000522, 2007.
Isaksen, K., Ødegård, R. S., Etzelmüller, B., Hilbich, C., Hauck, C., Farbrot, H., Eiken, T., Hygen, H. O., and Hipp, T. F.: Degrading mountain permafrost in Southern Norway: spatial and temporal variability of mean ground temperatures, 1999–2009, Permafrost Periglac., 22, 361–377, https://doi.org/10.1002/ppp.728, 2011.
Ishikawa, M.: Thermal regimes at the snow–ground interface and their implications for permafrost investigation, Geomorphology, 52, 105–120, https://doi.org/10.1016/S0169-555X(02)00251-9, 2003.
James, M., Lewkowicz, A. G., Smith, S. L., and Miceli, C. M.: Multi-decadal degradation and persistence of permafrost in the Alaska Highway corridor, northwest Canada, Environ. Res. Lett., 8, 045013, https://doi.org/10.1088/1748-9326/8/4/045013, 2013.
Karunaratne, K. and Burn, C.: Relations between air and surface temperature in discontinuous permafrost terrain near Mayo, Yukon Territory, Canadian J. Earth Sci., 41, 1437–1451, 2004.
Keller, M. and Gubler, H.: Interaction between snow cover and high-mountain permafrost, Murtel/Corvatsch, Swiss Alps, in: Proceedings after Sixth International Conference on Permafrost, Beijing, China, 332–337, 1993.
Kovacs, A., Gow, A. J., and Morey, R. M.: The in-situ dielectric constant of polar firn revisited, Cold Reg. Sci. Technol., 23, 245–256, https://doi.org/10.1016/0165-232X(94)00016-Q, 1995.
Langer, M., Westermann, S., Heikenfeld, M., Dorn, W., and Boike, J.: Satellite-based modeling of permafrost temperatures in a tundra lowland landscape, Remote Sens. Environ., 135, 12–24, https://doi.org/10.1016/j.rse.2013.03.011, 2013.
Lehning, M., Völksch, I., Gustafsson, D., Nguyen, T. A., Stähli, M., and Zappa, M.: ALPINE3D: a detailed model of mountain surface processes and its application to snow hydrology, Hydrol. Process., 20, 2111–2128, https://doi.org/10.1002/hyp.6204, 2006.
Lewkowicz, A. G., Bonnaventure, P. P., Smith, S. L., and Kuntz, Z.: Spatial and thermal characteristics of mountain permafrost, northwest Canada, Geogr. Ann. A, 94, 195–213, https://doi.org/10.1111/j.1468-0459.2012.00462.x, 2012.
Liestøl, O. and Sollid, J. L.: Glacier erosion and sedimentation at Hardangerjøkulen and Omsbreen, in: Field Guide to Excursion Organized in Conjunction with Symposium on Processes of Glacer Erosion and Sedimentation, 25–30 August, edited by: Orheim, O., Norwegian Polar Institute, Geilo, 1980.
Lilleøren, K. S., Humlum, O., Nesje, A., and Etzelmüller, B.: Holocene development and geomorphic processes at Omnsbreen, southern Norway: evidence for glacier–permafrost interactions, Holocene, 23, 796–809, https://doi.org/10.1177/0959683612471984, 2013.
Liston, G. E. and Sturm, M.: A snow-transport model for complex terrain, J. Glaciol., 44, 498–516, 1998.
Luetschg, M., Stoeckli, V., Lehning, M., Haeberli, W., and Ammann, W.: Temperatures in two boreholes at Flüela Pass, Eastern Swiss Alps: the effect of snow redistribution on permafrost distribution patterns in high mountain areas, Permafrost Periglac., 15, 283–297, https://doi.org/10.1002/ppp.500, 2004.
Luetschg, M., Lehning, M., and Haeberli, W.: A sensitivity study of factors influencing warm/thin permafrost in the Swiss Alps, J. Glaciol., 54, 696–704, https://doi.org/10.3189/002214308786570881, 2008.
Mohr, M.: New Routines for Gridding of Temperature and Precipitation Observations for "seNorge.no". Met.no Report 08/2008, available at: http://met.no/Forskning/Publikasjoner/Publikasjoner_1995_-_2012/Publikasjoner_2008/filestore/NewRoutinesforGriddingofTemperature.pdf, last access: (20 January 2013), 2008.
Ødegård, R. S., Sollid, J. L., and Liestøl, O.: Ground temperature measurements in mountain permafrost, Jotunheimen, southern Norway, Permafrost Periglac., 3, 231–234, https://doi.org/10.1002/ppp.3430030310, 1992.
Riseborough, D. and Smith, M.: Exploring the limits of permafrost., Seventh International Conference on Permafrost, Yellowknife, Canada, 935–941, 1998.
Roth, K. and Boike, J.: Quantifying the thermal dynamics of a permafrost site near Ny-Ålesund, Svalbard, Water Resour. Res., 37, 2901–2914, https://doi.org/10.1029/2000WR000163, 2001.
Saloranta, T. M.: Simulating snow maps for Norway: description and statistical evaluation of the seNorge snow model, The Cryosphere, 6, 1323–1337, https://doi.org/10.5194/tc-6-1323-2012, 2012.
seNorge.no: Gridded data sets of air temperature and snow depth for Norway, available at: www.seNorge.no (last access: 4 November 2013), 2013.
Smith, M. W. and Riseborough, D. W.: Permafrost monitoring and detection of climate change, Permafrost Periglac., 7, 301–309, https://doi.org/10.1002/(SICI)1099-1530(199610)7:4<301::AID-PPP231>3.0.CO;2-R, 1996.
Smith, M. W. and Riseborough, D. W.: Climate and the limits of permafrost: a zonal analysis, Permafrost Periglac., 13, 1–15, https://doi.org/10.1002/ppp.410, 2002.
Sollid, J. L., Holmlund, P., Isaksen, K., and Harris, C.: Deep permafrost boreholes in western Svalbard, northern Sweden and southern Norway, Norsk Geogr. Tidsskr., 54, 186–191, https://doi.org/10.1080/002919500448567, 2000.
Throop, J., Lewkowicz, A. G., and Smith, S. L.: Climate and ground temperature relations at sites across the continuous and discontinuous permafrost zones, northern Canada, Can. J. Earth Sc., 49, 865–876, https://doi.org/10.1139/e11-075, 2012.
Tveito, O. E., Førland, E. J., Heino, R., Hanssen-Bauer, I., Alexandersson, H., Dahlström, B., Drebs, A., Kern-Hansen, C., Jónsson, T., Laursen, E. V., and Westman, Y.: Nordic temperature maps (Nordklim), DNMI KLIMA Report 09/00, 2000.
Vonder Muhll, D., Stucki, T., and Haeberli, W.: Borehole temperatures in Alpine permafrost: a ten years series, in: Proceedings of the Seventh International Conference on Permafrost, Yellowknife, Canada, 1089–1095, 1998.
Westermann, S., Lüers, J., Langer, M., Piel, K., and Boike, J.: The annual surface energy budget of a high-arctic permafrost site on Svalbard, Norway, The Cryosphere, 3, 245–263, https://doi.org/10.5194/tc-3-245-2009, 2009.
Westermann, S., Wollschläger, U., and Boike, J.: Monitoring of active layer dynamics at a permafrost site on Svalbard using multi-channel ground-penetrating radar, The Cryosphere, 4, 475–487, https://doi.org/10.5194/tc-4-475-2010, 2010.
Westermann, S., Boike, J., Langer, M., Schuler, T. V., and Etzelmüller, B.: Modeling the impact of wintertime rain events on the thermal regime of permafrost, The Cryosphere, 5, 945–959, https://doi.org/10.5194/tc-5-945-2011, 2011.
Westermann, S., Schuler, T. V., Gisnås, K., and Etzelmüller, B.: Transient thermal modeling of permafrost conditions in Southern Norway, The Cryosphere, 7, 719–739, https://doi.org/10.5194/tc-7-719-2013, 2013.
Winstral, A., Elder, K., and Davis, R. E.: Spatial snow modeling of wind-redistributed snow using terrain-based parameters, J. Hydrometeorol., 3, 524–538, 2002.
Winther, J.-G., Godtliebsen, F., Gerland, S., and Isachsen, P. E.: Surface albedo in Ny-Ålesund, Svalbard: variability and trends during 1981–1997, Global Planet. Change, 32, 127–139, https://doi.org/10.1016/S0921-8181(01)00103-5, 2002.
Zhang, T.: Influence of the seasonal snow cover on the ground thermal regime: an overview, Rev. Geophys., 43, 1944–9208, https://doi.org/10.1029/2004rg000157, 2005.
Zhang, T., Barry, R. G., and Haeberli, W.: Numerical simulations of the influence of the seasonal snow cover on the occurrence of permafrost at high latitudes, Norsk Geografisk Tidsskrift – Norwegian J. Geography, 55, 261–266, https://doi.org/10.1080/00291950152746621, 2001.
