Articles | Volume 19, issue 10
https://doi.org/10.5194/tc-19-4525-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-19-4525-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Brief communication: Reanalyses underperform in cold regions, raising concerns for climate services and research
State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), National Tibetan Plateau Data Center, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China
Stephan Gruber
Department of Geography and Environmental Studies, Carleton University, Ottawa, Ontario, Canada
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Wen Sun and Bin Cao
EGUsphere, https://doi.org/10.5194/egusphere-2025-1828, https://doi.org/10.5194/egusphere-2025-1828, 2025
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Understanding the dynamics of permafrost heavily relies on process-based simulations. In this study, we introduce a new model specifically designed for permafrost applications, the Flexible Permafrost Model (FPM). This model serves as an adaptable framework for implementing innovative permafrost-related physics. Long-term ensemble simulations indicate that the permafrost temperature has increased by 0.26 °C since 1980 with a decreased area of ∼10.5 % over the Tibetan Plateau.
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
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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.
Niccolò Tubini and Stephan Gruber
EGUsphere, https://doi.org/10.5194/egusphere-2025-2649, https://doi.org/10.5194/egusphere-2025-2649, 2025
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This research introduces a new model for simulating how melting ground ice in permafrost reshapes the land surface over time. It shows that small differences in soil and the depth where ice is found can cause large differences in how the ground sinks or rises. This helps improves our ability to predict future impacts on terrain, ecosystems, and infrastructure as the climate warms.
Nicholas Brown and Stephan Gruber
EGUsphere, https://doi.org/10.5194/egusphere-2025-2658, https://doi.org/10.5194/egusphere-2025-2658, 2025
This preprint is open for discussion and under review for The Cryosphere (TC).
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This study improves how we track changes in permafrost by testing new ways to use ground temperature data. A set of five simple but powerful metrics was found to give a clearer picture of thawing than current methods. The results also show that the depth where sensors are placed can strongly affect measured warming rates. These findings help make permafrost monitoring more accurate and support better planning for a changing climate.
Wen Sun and Bin Cao
EGUsphere, https://doi.org/10.5194/egusphere-2025-1828, https://doi.org/10.5194/egusphere-2025-1828, 2025
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Understanding the dynamics of permafrost heavily relies on process-based simulations. In this study, we introduce a new model specifically designed for permafrost applications, the Flexible Permafrost Model (FPM). This model serves as an adaptable framework for implementing innovative permafrost-related physics. Long-term ensemble simulations indicate that the permafrost temperature has increased by 0.26 °C since 1980 with a decreased area of ∼10.5 % over the Tibetan Plateau.
Hosein Fereydooni, Stephan Gruber, David Stillman, and Derek Cronmiller
EGUsphere, https://doi.org/10.5194/egusphere-2025-1801, https://doi.org/10.5194/egusphere-2025-1801, 2025
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Detecting ground ice in permafrost is crucial for climate research and infrastructure, but traditional methods often struggle to distinguish it. This study examines the dielectric properties of ground ice as a unique fingerprint. Field measurements were taken at two Yukon permafrost sites: a retrogressive thaw slump and a pingo. Comparing these with electrical resistivity and impedance results, we found relaxation time is a more reliable indicator for ground ice detection.
Alessandro Cicoira, Samuel Weber, Andreas Biri, Ben Buchli, Reynald Delaloye, Reto Da Forno, Isabelle Gärtner-Roer, Stephan Gruber, Tonio Gsell, Andreas Hasler, Roman Lim, Philippe Limpach, Raphael Mayoraz, Matthias Meyer, Jeannette Noetzli, Marcia Phillips, Eric Pointner, Hugo Raetzo, Cristian Scapozza, Tazio Strozzi, Lothar Thiele, Andreas Vieli, Daniel Vonder Mühll, Vanessa Wirz, and Jan Beutel
Earth Syst. Sci. Data, 14, 5061–5091, https://doi.org/10.5194/essd-14-5061-2022, https://doi.org/10.5194/essd-14-5061-2022, 2022
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This paper documents a monitoring network of 54 positions, located on different periglacial landforms in the Swiss Alps: rock glaciers, landslides, and steep rock walls. The data serve basic research but also decision-making and mitigation of natural hazards. It is the largest dataset of its kind, comprising over 209 000 daily positions and additional weather data.
Francisco José Cuesta-Valero, Hugo Beltrami, Stephan Gruber, Almudena García-García, and J. Fidel González-Rouco
Geosci. Model Dev., 15, 7913–7932, https://doi.org/10.5194/gmd-15-7913-2022, https://doi.org/10.5194/gmd-15-7913-2022, 2022
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Inversions of subsurface temperature profiles provide past long-term estimates of ground surface temperature histories and ground heat flux histories at timescales of decades to millennia. Theses estimates complement high-frequency proxy temperature reconstructions and are the basis for studying continental heat storage. We develop and release a new bootstrap method to derive meaningful confidence intervals for the average surface temperature and heat flux histories from any number of profiles.
Élise G. Devoie, Stephan Gruber, and Jeffrey M. McKenzie
Earth Syst. Sci. Data, 14, 3365–3377, https://doi.org/10.5194/essd-14-3365-2022, https://doi.org/10.5194/essd-14-3365-2022, 2022
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Soil freezing characteristic curves (SFCCs) relate the temperature of a soil to its ice content. SFCCs are needed in all physically based numerical models representing freezing and thawing soils, and they affect the movement of water in the subsurface, biogeochemical processes, soil mechanics, and ecology. Over a century of SFCC data exist, showing high variability in SFCCs based on soil texture, water content, and other factors. This repository summarizes all available SFCC data and metadata.
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
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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.
Niccolò Tubini, Stephan Gruber, and Riccardo Rigon
The Cryosphere, 15, 2541–2568, https://doi.org/10.5194/tc-15-2541-2021, https://doi.org/10.5194/tc-15-2541-2021, 2021
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We present a new method to compute temperature changes with melting and freezing – a fundamental challenge in cryosphere research – extremely efficiently and with guaranteed correctness of the energy balance for any time step size. This is a key feature since the integration time step can then be chosen according to the timescale of the processes to be studied, from seconds to days.
John Mohd Wani, Renoj J. Thayyen, Chandra Shekhar Prasad Ojha, and Stephan Gruber
The Cryosphere, 15, 2273–2293, https://doi.org/10.5194/tc-15-2273-2021, https://doi.org/10.5194/tc-15-2273-2021, 2021
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We study the surface energy balance from a cold-arid permafrost environment in the Indian Himalayan region. The GEOtop model was used for the modelling of surface energy balance. Our results show that the variability in the turbulent heat fluxes is similar to that reported from the seasonally frozen ground and permafrost regions of the Tibetan Plateau. Further, the low relative humidity could be playing a critical role in the surface energy balance and the permafrost processes.
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
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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.
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Short summary
The climate-driven changes in cold regions have an outsized importance for local resilient communities and for global climate through teleconnections. We show that reanalyses are less accurate in cold regions compared to other more populated regions, coincident with the low density of observations. Our findings likely point to similar gaps in our knowledge and capabilities of climate research and services in cold regions.
The climate-driven changes in cold regions have an outsized importance for local resilient...