Articles | Volume 13, issue 8
https://doi.org/10.5194/tc-13-2087-2019
© Author(s) 2019. 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-13-2087-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Aug 2019
Research article |
| 01 Aug 2019
| 01 Aug 2019
Permafrost variability over the Northern Hemisphere based on the MERRA-2 reanalysis
Earth System Science Interdisciplinary Center, University of Maryland, College Park, Maryland, USA
Global Modeling and Assimilation Office, NASA Goddard Space Flight
Center, Greenbelt, Maryland, USA
now at: Climate and Ecosystem Sciences Division, Lawrence Berkeley
National Laboratory, Berkeley, California, USA
now at: Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
Randal D. Koster
Global Modeling and Assimilation Office, NASA Goddard Space Flight
Center, Greenbelt, Maryland, USA
Rolf H. Reichle
Global Modeling and Assimilation Office, NASA Goddard Space Flight
Center, Greenbelt, Maryland, USA
Barton A. Forman
Department of Civil and Environmental Engineering, University of
Maryland, College Park, Maryland, USA
Yuan Xue
Department of Civil and Environmental Engineering, University of
Maryland, College Park, Maryland, USA
now at: Department of Geography and GeoInformation Science, George Mason University, Fairfax, Virginia, USA
Richard H. Chen
Department of Electrical Engineering, University of Southern
California, Los Angeles, California, USA
Mahta Moghaddam
Department of Electrical Engineering, University of Southern
California, Los Angeles, California, USA
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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
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We assess spatio-temporal permafrost variations in selected rock walls in Norway over the last 120 years. Ground temperature is modelled using the two-dimensional ground heat flux model CryoGrid 2D along nine profiles. Permafrost probably occurs at most sites. All simulations show increasing ground temperature from the 1980s. Our simulations show that rock wall permafrost with a temperature of −1 °C at 20 m depth could thaw at this depth within 50 years.
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
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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
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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
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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
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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
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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.
Tamara Mathys, Christin Hilbich, Lukas U. Arenson, Pablo A. Wainstein, and Christian Hauck
The Cryosphere, 16, 2595–2615, https://doi.org/10.5194/tc-16-2595-2022, https://doi.org/10.5194/tc-16-2595-2022, 2022
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With ongoing climate change, there is a pressing need to understand how much water is stored as ground ice in permafrost. Still, field-based data on permafrost in the Andes are scarce, resulting in large uncertainties regarding ground ice volumes and their hydrological role. We introduce an upscaling methodology of geophysical-based ground ice quantifications at the catchment scale. Our results indicate that substantial ground ice volumes may also be present in areas without rock glaciers.
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
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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
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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
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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
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This study presents rock surface temperatures (RSTs) of steep high-Arctic rock walls on Svalbard from 2016 to 2020. The field data show that coastal cliffs are characterized by warmer RSTs than inland locations during winter seasons. By running model simulations, we analyze factors leading to that effect, calculate the surface energy balance and simulate different future scenarios. Both field data and model results can contribute to a further understanding of RST in high-Arctic rock walls.
Thomas Schneider von Deimling, Hanna Lee, Thomas Ingeman-Nielsen, Sebastian Westermann, Vladimir Romanovsky, Scott Lamoureux, Donald A. Walker, Sarah Chadburn, Erin Trochim, Lei Cai, Jan Nitzbon, Stephan Jacobi, and Moritz Langer
The Cryosphere, 15, 2451–2471, https://doi.org/10.5194/tc-15-2451-2021, https://doi.org/10.5194/tc-15-2451-2021, 2021
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Climate warming puts infrastructure built on permafrost at risk of failure. There is a growing need for appropriate model-based risk assessments. Here we present a modelling study and show an exemplary case of how a gravel road in a cold permafrost environment in Alaska might suffer from degrading permafrost under a scenario of intense climate warming. We use this case study to discuss the broader-scale applicability of our model for simulating future Arctic infrastructure failure.
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
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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
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A sub-grid representation of excess ground ice in the Community Land Model (CLM) is developed as novel progress in modeling permafrost thaw and its impacts under the warming climate. The modeled permafrost degradation with sub-grid excess ice follows the pathway that continuous permafrost transforms into discontinuous permafrost before it disappears, including surface subsidence and talik formation, which are highly permafrost-relevant landscape changes excluded from most land models.
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.
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
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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
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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
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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
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We present a long-term multisite electrical resistivity tomography monitoring network (more than 1000 datasets recorded from six mountain permafrost sites). Despite harsh and remote measurement conditions, the datasets are of good quality and show consistent spatio-temporal variations yielding significant added value to point-scale borehole information. Observed long-term trends are similar for all permafrost sites, showing ongoing permafrost thaw and ground ice loss due to climatic conditions.
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
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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
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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
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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
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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
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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
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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.
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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.
The active layer thickness (ALT) in middle-to-high northern latitudes from 1980 to 2017 was...
