Description: This dataset contains geographical features representing selected infrastructures (houses, roads, airfield, pipelines etc.) in the town Longyearbyen on Svalbard. Each feature has attributes listing relevant classifiers, such as: - the type of infrastructure (residential building, road, pipeline, etc.) - the shape of the feature (flat, sloped, pitched, domed, barrel-shaped) - the type of surface material (wood, concrete, asphalt, etc.) - the background setting (rock, sediments, sea, etc.) - its current status as actively used or inactive infrastructure. -- All feature locations and attributes have been validated either by on-site inspection, or by Google Street View imagery (validation method indicated in feature attributes). -- Photos are provided for most of the features that were field validated.

Description: This dataset contains geographical features representing selected infrastructures (houses, roads, airfields, pipelines etc.) in some West Greenland towns and settlements. Each feature has attributes listing relevant classificiers, such as: - the type of infrastructure (residential building, road, pipeline, etc.) - the shape of the feature (flat, sloped, pitched, domed, barrel-shaped) - the type of surface material (wood, concrete, asphalt, etc.) - the background setting (bedrock, sediments, sea, etc.) - it current status as actively used or inactive infrastructure. -- All feature locations and attributes have been validated either by on-site inspection, or by Google Street View imagery (validation method indicated in feature attributes). -- Photos are provided for most of the features that were field validated.

Description: This paper provides a snapshot of the permafrost thermal state in the Nordic area obtained during the International Polar Year (IPY) 2007-2009. Several intensive research campaigns were undertaken within a variety of projects in the Nordic countries to obtain this snapshot. We demonstrate for Scandinavia that both lowland permafrost in palsas and peat plateaus, and large areas of permafrost in the mountains are at temperatures close to 0°C, which makes them sensitive to climatic changes. In Svalbard and northeast Greenland, and also in the highest parts of the mountains in the rest of the Nordic area, the permafrost is somewhat colder, but still only a few degrees below the freezing point. The observations presented from the network of boreholes, more than half of which were established during the IPY, provide an important baseline to assess how future predicted climatic changes may affect the permafrost thermal state in the Nordic area. Time series of active-layer thickness and permafrost temperature conditions in the Nordic area, which are generally only 10 years in length, show generally increasing active-layer depths and rising permafrost temperatures.

Description: Interferometric Synthetic Aperture Radar (InSAR) images (L1 Single Look Complex data from ESA/Copernicus Sentinel-1) were acquired between May and September during the thawing seasons from 2015 to 2019, over the area of Ilulissat, West Greenland. Rasters of thaw-season ground surface displacements were obtained from the interferometric processing of the SAR scenes. The 2015-2019 average seasonal displacement (S) and long-term deformation rate (R) were derived by least-squares inversion from the surface displacement rasters. In addition, active layer thicknesses (ALT) probed in Ilulissat at the end of the summers of 2020 and 2021 were extrapolated using a vegetation map derived from a Random Forest classification of multi-temporal Sentinel-2 optical images. The average seasonal displacement and extrapolated ALT were finally used to estimate the amount of ice present in the active layer, indicating the frost susceptibility of the ground. This dataset first contains the yearly thaw-season surface displacement rasters in the radar line-of-sight (LOS) direction, and the derived average seasonal and long-term deformation rasters. Secondly, the ALT measurements and floristic data used as inputs and validation in the study are provided along with the land cover classification, extrapolated ALT and frost susceptibility index rasters.

Description: Permafrost warming has the potential to amplify global climate change, because when frozen sediments thaw it unlocks soil organic carbon. Yet to date, no globally consistent assessment of permafrost temperature change has been compiled. Here we use a global data set of permafrost temperature time series from the Global Terrestrial Network for Permafrost to evaluate temperature change across permafrost regions for the period since the International Polar Year (2007–2009). During the reference decade between 2007 and 2016, ground temperature near the depth of zero annual amplitude in the continuous permafrost zone increased by 0.39 ± 0.15 °C. Over the same period, discontinuous permafrost warmed by 0.20 ± 0.10 °C. Permafrost in mountains warmed by 0.19 ± 0.05 °C and in Antarctica by 0.37 ± 0.10 °C. Globally, permafrost temperature increased by 0.29 ± 0.12 °C. The observed trend follows the Arctic amplification of air temperature increase in the Northern Hemisphere. In the discontinuous zone, however, ground warming occurred due to increased snow thickness while air temperature remained statistically unchanged.

Description: Analysis of stable oxygen isotope (δ18O) characteristics is a useful tool to investigate water provenance in glacier river systems. In order to attain knowledge on the diversity of δ18O variations in Greenlandic rivers, we examined two contrasting glacierised catchments disconnected from the Greenland Ice Sheet (GrIS). At the Mittivakkat Gletscher river, a small river draining a local temperate glacier in southeast Greenland, diurnal oscillations in δ18O occurred with a 3 h time lag to the diurnal oscillations in run-off. The mean annual δ18O was −14.68 ± 0.18 ‰ during the peak flow period. A hydrograph separation analysis revealed that the ice melt component constituted 82 ± 5 % of the total run-off and dominated the observed variations during peak flow in August 2004. The snowmelt component peaked between 10:00 and 13:00 local time, reflecting the long travel time and an inefficient distributed subglacial drainage network in the upper part of the glacier. At the Kuannersuit Glacier river on the island Qeqertarsuaq in west Greenland, the δ18O characteristics were examined after the major 1995–1998 glacier surge event. The mean annual δ18O was −19.47 ± 0.55 ‰. Despite large spatial variations in the δ18O values of glacier ice on the newly formed glacier tongue, there were no diurnal oscillations in the bulk meltwater emanating from the glacier in the post-surge years. This is likely a consequence of a tortuous subglacial drainage system consisting of linked cavities, which formed during the surge event. Overall, a comparison of the δ18O compositions from glacial river water in Greenland shows distinct differences between water draining local glaciers and ice caps (between −23.0 and −13.7 ‰) and the GrIS (between −29.9 and −23.2 ‰). This study demonstrates that water isotope analyses can be used to obtain important information on water sources and the subglacial drainage system structure that is highly desired for understanding glacier hydrology.

Description: Contributing authors : Carl Barrette, Diane Chaumont, Chris Derksen, James Hamilton, Stephen Howell, Thomas Ingeman-Nielsen, Thomas James, Diane Lavoie, Sergey Marchenko, Steffen M. Olsen, Christian B. Rodehacke, Martin Sharp, Sharon L. Smith, Martin Stendel, Rasmus T. Tonboe

Description: The fate of infrastructure in the Arctic and in high altitude regions is heavily depending on the stability of frozen ground which it is built on. Climate change and consequent degradation of permafrost will negatively affect various infrastructure types and can cause ultimate failure. Comprehensive pan-Arctic assessments are urgently needed to better quantify environmental, economic and societal risks and to help adaptation planning. The use of physical models can be a powerful tool for risk evaluation, but modelling challenges remain with respect to resolving construction details at infrastructure scales together with decadal-scale climate change impacts. Here we used the dynamic permafrost land-surface model CryoGrid3 (including a soil subsidence module) to capture both - the effects from the interaction of small-scale infrastructure with permafrost and large-scale climate change effects evolving in the 21st century under an extensive climate warming scenario. We discuss how infrastructure can affect ground temperatures, and how climate change increases the risk of future infrastructure failure. As an exemplary case of permafrost-affected infrastructure failure, we modelled a gravel road on continuous permafrost at Prudhoe Bay (Alaska). We investigate the timing of infrastructure failure from soil subsidence in dependence of assumed embankment thickness and depth of excess ice in the ground.

Description: The fate of infrastructure in the Arctic is heavily depending on the stability of frozen ground which it is built on. Climate change and consequent degradation of permafrost will negatively affect various infrastructure types and can cause ultimate failure. Comprehensive pan-Arctic assessments are urgently needed to better quantify environmental, economic and societal risks and to help adaptation planning. The use of physical models can be a powerful tool for risk evaluation, but modelling challenges remain with respect to resolving construction details at infrastructure scales together with decadal-scale climate change impacts. Here we used the dynamic permafrost land-surface model CryoGrid3 to capture both - the effects from the interaction of small-scale infrastructure with permafrost and large-scale climate change effects evolving in the 21century under an extensive warming scenario. We discuss how infrastructure can affect ground temperatures, and how climate change increases the risk of future infrastructure failure. We modelled two exemplary cases of permafrost-affected infrastructure: a gravel road on continuous permafrost at Prudhoe Bay (Alaska), and the case of a diesel tank facility at Norilsk (Siberia) placed on permafrost already subject to degradation under present day climate. We use the latter example to discuss environmental risks from contamination of hazardous legacy waste stored on and in permafrostand discuss the urgency for near-term policy strategies.

Description: The CryoGrid community model is a flexible toolbox for simulating the ground thermal regime and the ice-water balance for permafrost and glaciers, extending a well-established suite of permafrost models (CryoGrid 1, 2, and 3). The CryoGrid community model can accommodate a wide variety of application scenarios, which is achieved by fully modular structures through object-oriented programming. Different model components, characterized by their process representations and parameterizations, are realized as classes (i.e., objects) in CryoGrid. Standardized communication protocols between these classes ensure that they can be stacked vertically. For example, the CryoGrid community model features several classes with different complexity for the seasonal snow cover, which can be flexibly combined with a range of classes representing subsurface materials, each with their own set of process representations (e.g., soil with and without water balance, glacier ice). We present the CryoGrid architecture as well as the model physics and defining equations for the different model classes, focusing on one-dimensional model configurations which can also interact with external heat and water reservoirs. We illustrate the wide variety of simulation capabilities for a site on Svalbard, with point-scale permafrost simulations using, e.g., different soil freezing characteristics, drainage regimes, and snow representations, as well as simulations for glacier mass balance and a shallow water body. The CryoGrid community model is not intended as a static model framework but aims to provide developers with a flexible platform for efficient model development. In this study, we document both basic and advanced model functionalities to provide a baseline for the future development of novel cryosphere models.