Source: https://uspermafrost.org/publications/pma/2018-january-permafrost-alert.html
Timestamp: 2019-04-22 18:24:19+00:00

Document:
2018018635 Appels, Willemijn M. (University of Saskatchewan, Global Institute for Water Security, Saskatoon, SK, Canada); Coles, Anna E. and McDonnell, Jeffrey J. Infiltration into frozen soil; from core-scale dynamics to hillslope-scale connectivity: Hydrological Processes, 32(1), p. 66-79, illus. incl. 1 table, 67 ref., January 1, 2018.
Infiltration into frozen soil is a key hydrological process in cold regions. Although the mechanisms behind point-scale infiltration into frozen soil are relatively well understood, questions remain about upscaling point-scale results to estimate hillslope-scale run-off generation. Here, we tackle this question by combining laboratory, field, and modelling experiments. Six large (0.30-m diameter by 0.35-m deep) soil cores were extracted from an experimental hillslope on the Canadian Prairies. In the laboratory, we measured run-off and infiltration rates of the cores for two antecedent moisture conditions under snowmelt rates and diurnal freeze-thaw conditions observed on the same hillslope. We combined the infiltration data with spatially variable data from the hillslope, to parameterise a surface run-off redistribution model. We used the model to determine how spatial patterns of soil water content, snowpack water equivalent (SWE), and snowmelt rates affect the spatial variability of infiltration and hydrological connectivity over frozen soil. Our experiments showed that antecedent moisture conditions of the frozen soil affected infiltration rates by limiting the initial soil storage capacity and infiltration front penetration depth. However, shallow depths of infiltration and refreezing created saturated conditions at the surface for dry and wet antecedent conditions, resulting in similar final infiltration rates (0.3 mm hr-1). On the hillslope-scale, the spatial variability of snowmelt rates controlled the development of hydrological connectivity during the 2014 spring melt, whereas SWE and antecedent soil moisture were unimportant. Geostatistical analysis showed that this was because SWE variability and antecedent moisture variability occurred at distances shorter than that of topographic variability, whereas melt variability occurred at distances longer than that of topographic variability. The importance of spatial controls will shift for differing locations and winter conditions. Overall, our results suggest that run-off connectivity is determined by (a) a pre-fill phase, during which a thin surface soil layer wets up, refreezes, and saturates, before infiltration excess run-off is generated and (b) a subsequent fill-and-spill phase on the surface that drives hillslope-scale run-off. Abstract Copyright (2010), John Wiley & Sons, Ltd.
2018014291 Tai Bowen (Beijing Jiaotong University, School of Civil Engineering, Beijing, China); Liu Jiankun; Yue Zurun; Liu Jingyu; Tian Yahu and Wang Tengfei. Effect of sunny-shady slopes and strike on thermal regime of subgrade along a high-speed railway in cold regions, China: Engineering Geology, 232, p. 182-191, illus. incl. 2 tables, sketch map, 54 ref., January 8, 2018.
Ground temperature and deformation of embankment were monitored at typical sections of the Harbin-Qiqihar high speed railway (HSR) to investigate complex causes of differential embankment deformation due to sunny-shady slopes and route strike in cold regions. Maximum frozen depth, ground temperature, frost heave, and thaw settlement of the embankment in the sunny and shady sides were analyzed relative to measurement dates, and then a numerical model for the embankment temperature filed was also established. On these bases, the influence of route strike on the embankment thermal regime and its mechanism were then revealed; and proper engineering countermeasures were proposed to mitigate the transverse embankment thermal difference; the formation mechanism of the differential deformation due to sunny-shady slopes was discussed. The results showed that both temperature and maximum frozen depth of the sunny side were greater than the shady side, whereas the cumulative frost heave of the sunny side was less than the shady side with opposite trends found for the cumulative thaw settlement. The temperature difference between the sunny and shady shoulders decreased gradually with increasing strike angle. The findings are potentially helpful for better understanding differential embankment deformation in cold regions, as well as for improving HSR embankment quality and operational safety.
2018018629 Qin Yanhui (Chinese Academy of Sciences, Northwest Institute of Eco-Environment and Resources, Lanzhou, China); Wu Tonghua; Wu Xiaodong; Li Ren; Xie Changwei; Qiao Yongping; Hu Guojie; Zhu Xiaofan; Wang Weihua and Shang Wen. Assessment of reanalysis soil moisture products in the permafrost regions of the central of the Qinghai-Tibet Plateau: Hydrological Processes, 31(26), p. 4647-4659, illus. incl. 3 tables, sketch map, 100 ref., December 30, 2017.
The long-term and large-scale soil moisture (SM) record is important for understanding land atmosphere interactions and their impacts on the weather, climate, and regional ecosystem. SM products are one of the parameters used in some Earth system models, but these records require evaluation before use. The water resources on the Qinghai-Tibet Plateau (QTP) are important to the water security of billions of people in Asia. Therefore, it is necessary to know the SM conditions on the QTP. In this study, the evaluation metrics of multilayer (0-10, 10-40, and 40-100 cm) SM in different reanalysis datasets of the European Centre for Medium-Range Weather Forecasts interim reanalysis (ERA-Interim [ERA]), National Centers for Environmental Prediction Climate Forecast System and the Climate Forecast System version 2 (CFSv2), and China Meteorological Administration Land Data Assimilation System (CLDAS) are compared with in situ observations at 5 observation sites, which represent alpine meadow, alpine swamp meadow, alpine grassy meadow, alpine desert steppe, and alpine steppe environments during the thawing season from January 1, 2011, to December 31, 2013, on the QTP. The ERA SM remains constant at approximately 0.2 m3·m-3 at all observation sites during the entire thawing season. The CLDAS and CFSv2 SM products show similar patterns with those of the in situ SM observations during the thawing season. The CLDAS SM product performs better than the CFSv2 and ERA for all vegetation types except the alpine swamp meadow. The results indicate that the soil texture and land cover types play a more important role than the precipitation to increase the biases of the CLDAS SM product on the QTP. Abstract Copyright (2010), John Wiley & Sons, Ltd.
2018016831 Huang Yan (East China Normal University, Laboratory of Geographic Information Science, Shanghai, China); Liu Hongxing; Hinkel, Kenneth; Yu Bailang; Beck, Richard and Wu Jianping. Analysis of thermal structure of Arctic lakes at local and regional scales using in situ and multidate Landsat-8 data: Water Resources Research, 53(11), p. 9642-9658, illus. incl. 2 tables, sketch map, 53 ref., November 2017.
The Arctic coastal plain is covered with numerous thermokarst lakes. These lakes are closely linked to climate and environmental change through their heat and water budgets. We examined the intralake thermal structure at the local scale and investigated the water temperature pattern of lakes at the regional scale by utilizing extensive in situ measurements and multidate Landsat-8 remote sensing data. Our analysis indicates that the lake skin temperatures derived from satellite thermal sensors during most of the ice-free summer period effectively represent the lake bulk temperature because the lakes are typically well-mixed and without significant vertical stratification. With the relatively high-resolution Landsat-8 thermal data, we were able to quantitatively examine intralake lateral temperature differences and gradients in relation to geographical location, topography, meteorological factors, and lake morphometry for the first time. Our results suggest that wind speed and direction not only control the vertical stratification but also influences lateral differences and gradients of lake surface temperature. Wind can considerably reduce the intralake temperature gradient. Interestingly, we found that geographical location (latitude, longitude, distance to the ocean) and lake morphometry (surface size, depth, volume) not only control lake temperature regionally but also affect the lateral temperature gradient and homogeneity level within each individual lake. For the Arctic coastal plain, at regional scales, inland and southern lakes tend to have larger horizontal temperature differences and gradients compared to coastal and northern lakes. At local scales, large and shallow lakes tend to have large lateral temperature differences relative to small and deep lakes. Abstract Copyright (2017), . American Geophysical Union. All Rights Reserved.
2018013789 Lehn, Gregory O. (Northwestern University, Department of Earth and Planetary Sciences, Evanston, IL); Jacobson, A. D.; Douglas, T. A.; McClelland, J. W.; Barker, A. J. and Khosh, M. S. Constraining seasonal active layer dynamics and chemical weathering reactions occurring in North Slope Alaskan watersheds with major ion and isotope (d34SSO4, d13CDIC, 87Sr/86Sr, d44/40Ca, and d44/42Ca) measurements: Geochimica et Cosmochimica Acta, 217, p. 399-420, illus. incl. sketch map, 185 ref., November 15, 2017. Includes appendices.
Rising air temperatures in the Arctic may destabilize a large pool of organic carbon stored in permafrost, thereby causing a positive feedback to global climate warming. Permafrost thaw could also deepen hydrologic flow paths and expose previously frozen rock and mineral fragments to chemical weathering. Future shifts in the inorganic solute geochemistry of Arctic rivers may signal changes in soil processes that also affect organic carbon storage. Tracing permafrost thaw with dissolved riverine loads requires understanding the spatial and seasonal variation of chemical weathering reactions and other biogeochemical phenomena that affect elemental mass-transport. To help identify connections between mineral weathering and active layer processes, we studied the major ion and isotope (d34SSO4, d13CDIC, 87Sr/86Sr, d44/40Ca, and d44/42Ca) geochemistry of five streams draining the North Slope of Alaska. Continuous permafrost underlies all streams, but the Atigun River, Roche Moutonnee Creek, and Trevor Creek primarily drain bare bedrock outcrops in the Brooks Range, while the Upper Kuparuk River and Imnavait Creek primarily drain tundra. In total, we collected 546 water samples spanning the spring freshet through fall freeze-up in 2009 and 2010. We also analyzed snow, rock, sediment, soil, and plant samples. Major ion ratios and d13CDIC values point to the overall dominance of carbonate weathering by carbonic and sulfuric acids, with additional influences from atmospheric deposition, plant decay, sulfate salt dissolution, and silicate weathering by carbonic acid. d13CDIC values may also reflect partial equilibration with soil and atmospheric CO2. All streams display large seasonal variations in major ion ratios and d13CDIC values that are consistent with progressive deepening of the seasonally thawed zone over the summer. In the mountain watersheds, carbonate weathering dominates during the spring and summer, while sulfate salt (primarily CaSO4 and MgSO4) dissolution dominates during the fall. Riverine d34SSO4 values reveal that the sulfate salts are secondary precipitates. We propose a conceptual model where cryoconcentration in soils during the late fall and winter causes secondary mineral formation at depth and re-exposure during subsequent thaw seasons produces the observed geochemical signals in rivers. The tundra streams lack definitive evidence for sulfate salt dissolution, presumably because thick peat soils limit the exposure and weathering of underlying glacial sediment where the salts are expected to form and dissolve. Appearance of a sulfate salt dissolution signal in tundra streams may correlate with future permafrost degradation. Carbonate weathering dominates riverine 87Sr/86Sr ratios, but the compositional heterogeneity of bedrock limits interpretation of the data. All rivers have higher d44/40Ca values compared to bedrock, likely due to plant uptake of lighter Ca isotopes. In the tundra watersheds, freshet d44/40Ca values were 0.10-0.20 ppm lower than summer and fall values. These trends likely reflect contributions from plant decay, as comparison between d44/40Ca and d44/42Ca values suggests that all isotopic variation is mass-dependent with minimal radiogenic 40Ca inputs from the weathering of old silicate minerals with high K/Ca ratios.
2018013850 Loiko, Sergey V. (Tomsk State University, Laboratory of Biogeochemical and Remote Monitoring Techniques Enviornment, Tomsk, Russian Federation); Pokrovsky, Oleg S.; Raudina, Tatiana V.; Lim, Artyom; Kolesnichenko, Larisa G.; Shirokova, Liudmila S.; Vorobyev, Sergey N. and Kirpotin, Sergey N. Abrupt permafrost collapse enhances organic carbon, CO2, nutrient and metal release into surface waters: Chemical Geology, 471, p. 153-165, illus. incl. 3 tables, sketch map, 81 ref., November 5, 2017. Includes appendices.
Thawing of frozen peat in discontinuous permafrost zones may significantly modify the environment at local (slumps and engineering damages) and global (greenhouse gases regime) scales. We studied the aquatic geochemistry of CO2, CH4, dissolved organic carbon (DOC), P, Si, and colloidal trace metal from hollows, depressions, permafrost subsidences and soil waters in the actively thawing discontinuous permafrost zone of Western Siberia Lowland (WSL). This site of abrupt permafrost collapse is dominated by minerotrophic fens located within the flat mound peat bog. The CO2, DOC, major and trace metal concentrations decreased with the increase of the surface area of the water body, along the hydrological continuum (soil water ® hollows ® depressions and permafrost subsidences ® thaw ponds ® thermokarst lakes). Aqueous concentrations of CO2, CH4, Ca, Si, P, Al, Fe, Nd, and U were a factor of 4 to 10 higher in the site of catastrophic thaw compared to the steady thawing of a palsa peat bog that was previously studied in the same region. The colloids (1 kDa-0.45 mm) formed in hot spots were strongly enriched in Fe, Al, and trivalent and tetravalent hydrolysates relative to organic carbon. Because the increase in the thickness of the thawing depth intensifies the input of inorganic components from deep mineral horizons, abrupt permafrost thaw enriches the surface waters in Al-rich colloids and low molecular weight organic complexes. As a result, the WSL's surface water colloidal composition may shift from DOM-rich and DOM-Fe-rich to DOM-Al-rich, and the release of low-soluble trivalent and tetravalent hydrolysates from the soil to the river will increase. We hypothesize that in sites of abrupt permafrost thaw, there is direct mobilization of soil waters to a hydrological network (rivers and lakes) and there is minimal transformation by autochthonous processes, which is unlike the case of steady permafrost thawing. Therefore, the change in physical factors, such as water pathways and the water residence time, within a given elementary landscape will likely control the overall impact of on-going permafrost thaw on both the surface water chemistry and dissolved greenhouse gas pattern of the territory. For this, high-resolution (< 2 m) remote sensing analysis of water dynamics in the permafrost landscape is necessary.
2018018311 Pratt, Dyan L. (University of Saskatchewan, Global Institute for Water Security, Saskatoon, SK, Canada) and McDonnell, Jeffrey J. A portable experimental hillslope for frozen ground studies: Hydrological Processes, 31(24), p. 4450-4457, illus. incl. 1 table, 26 ref., November 30, 2017. Includes appendices.
Frozen ground hydrological effects on runoff, storage, and release have been observed in the field and tested in numerical models, but few physical models of frozen slopes (at scales from 1 to 15 m) exist partly because the design of such an experiment requires new engineering design for realistic whole-slope freezing and physical model innovation. Here, we present a new freezable tilting hillslope physical model for hydrological system testing under a variety of climate conditions with the ability to perform multiple (up to 20 per year) freeze-thaw cycles. The 4 ´ 2 m hillslope is mobile and tiltable on the basis of a modified tri-axle 4.88-m (16') dump trailer to facilitate testing multiple configurations. The system includes controllable boundary conditions on all surfaces; examples of side and baseflow boundary conditions include permeable membranes, impermeable barriers, semipermeable configurations, and constant head conditions. To simulate cold regions and to freeze the hillslope in a realistic and controlled manner, insulation and a removable freezer system are incorporated onto the top boundary of the hillslope. The freezing system is designed to expedite the freezing process by the addition of a 10,130-KJ (9,600-BTU) refrigeration coil to the top-centre of the insulated ceiling. Centre placement provides radial freezing of the hillslope in a top-down fashion, similar to what natural systems encounter in the environment. The perimeter walls are insulated with 100 mm of spray foam insulation, whereas the base of the hillslope is not insulated to simulate natural heat fluxes beneath the frozen layer of soil. Our preliminary testing shows that covers can be frozen down to -10 °C in approximately 7 days, with subsequent thaw on a similar time frame. Abstract Copyright (2010), John Wiley & Sons, Ltd.
2018013902 You Yanhui (Chinese Academy of Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Lanzhou, China); Wang Jinchang; Wu Qingbai; Yu Qihao; Pan Xicai; Wang Xinbin and Guo Lei. Causes of pile foundation failure in permafrost regions; the case study of a dry bridge of the Qinghai-Tibet Railway: Engineering Geology, 230, p. 95-103, illus. incl. sects., sketch map, 46 ref., November 29, 2017.
Pile foundations are widely used to support dry bridges crossing large extents of warm and ice-rich permafrost zones along the Qinghai-Tibet Railway (QTR). The performance of these pile foundations are related to permafrost conditions surrounding the piles. However, the impacts of permafrost degradation on the stability of pile foundations have been rarely investigated. In this study, permafrost degradation has been assessed around several pile foundations in the Tanggula Mountain area along the QTR 15 years after the first field investigation in 2001 for the construction of the QTR. This assessment is mainly based on drilling, geophysical surveys, and monitoring of the settlements affecting the pile foundations. The permafrost in contact with the piles has significantly thinned after the piles were casted-in-place and put into service about 8 years ago. Moreover, the thickness of residual permafrost is less than the embedment length for some piles and, therefore, the adfreeze bond between the piles and permafrost has significantly decreased. In addition, artesian sub-permafrost groundwater has been observed around the middle-lower and below the piles. Due to this sub-permafrost aquifer, the end bearing capacity of the piles and the friction between the piles and thawed soils have also probably decreased. The applied load on the piles is now supported by the residual permafrost resulting in large settlements of the piles. The thaw consolidation and settlement of degrading permafrost have also potentially contributed to the total settlement. According to the investigation presented herein, the occurrence of sub-permafrost aquifer which was induced by permafrost degradation is the primary cause of pile settlements. The failure mechanisms of the piles as revealed by this assessment are useful for the design and maintenance of piles in warm and ice-rich permafrost regions. Moreover, the use of geophysical methods for investigating pile foundation failure due to permafrost degradation has proved effective.
2018010680 Ban Yunyun (China Agricultural University, College of Water Resources and Civil Engineering, Beijing, China); Lei Tingwu; Chen Chao; Yin Zhe and Qian Dengfeng. Meltwater erosion process of frozen soil as affected by thawed depth under concentrated flow in high altitude and cold regions: Earth Surface Processes and Landforms, 42(13), p. 2139-2146, illus. incl. 3 tables, 45 ref., October 2017.
Changes in thawed depth of frozen soil caused by diurnal and seasonal temperature fluctuations are commonly found in high altitude and latitude regions of the world. These changes significantly influence hydrologic and erosion processes. Experimental data are necessary to improve the understanding and modeling of the phenomenon. Laboratory experiments were conducted in Beijing to assess the impacts of thawed soil depth, slope gradient, and flow rate on soil erosion by concentrated meltwater flow over an underlying frozen soil layer. Soil samples from watershed were filled in flumes, saturated before being frozen. After the soil was completely frozen, flumes were taken out of storage to thaw the frozen soil from top to the designed depths. Meltwater flow was simulated using a tank filled with water and icecubes at approximately 0°C. The erosion experiments involved four thawed soil depths of 1, 2, 5, and 10 cm; three slope gradients of 5°, 10°, and 15°; and three flow rates of 1, 2, and 4 l/min; and seven rill lengths of 0.5, 1, 2, 3, 4, 5, and 6 m. Sediment-laden water samples were collected at the lower end of the flume for determination of sediment concentration. The results showed that sediment concentration increased exponentially with rill length to approach a maximum value. The sediment concentrations were closely correlated with thawed soil depth, flow rate, and slope gradient. Shallower thawed depths delivered more sediments than deeper thawed depths. Slope gradient was the primary factor responsible for severe erosion. The effect of flow rate on sediment concentration which decreased with increasing slope gradient, was not as significant as that of slope gradient. Results from these experiments are useful for understanding the effect of thawed soil depth on erosion process in thawed soils subject to freezing and for estimating erosion model parameters. Copyright Copyright 2017 John Wiley & Sons, Ltd.
2018010161 Riedel, M. (Leibniz Institute for Marine Sciences, Helmholtz Centre for Ocean Research Kiel, Kiel, Germany); Brent, T. A.; Taylor, G.; Taylor, A. E.; Hong, J. K.; Jin, Y. K. and Dallimore, S. R. Evidence for gas hydrate occurrences in the Canadian Arctic Beaufort Sea within permafrost-associated shelf and deep-water marine environments: Marine and Petroleum Geology, 81, p. 66-78, illus. incl. sects., sketch map, 58 ref., March 2017.
The presence of a wedge of offshore permafrost on the shelf of the Canadian Beaufort Sea has been previously recognized and the consequence of a prolonged occurrence of such permafrost is the possibility of an underlying gas hydrate regime. We present the first evidence for wide-spread occurrences of gas hydrates across the shelf in water depths of 60-100 m using 3D and 2D multichannel seismic (MCS) data. A reflection with a polarity opposite to the seafloor was identified ~1000 m below the seafloor that mimics some of the bottom-simulating reflections (BSRs) in marine gas hydrate regimes. However, the reflection is not truly bottom-simulating, as its depth is controlled by offshore permafrost. The depth of the reflection decreases with increasing water depth, as predicted from thermal modeling of the late Wisconsin transgression. The reflection crosscuts strata and defines a zone of enhanced reflectivity beneath it, which originates from free gas accumulated at the phase boundary over time as permafrost and associated gas hydrate stability zones thin in response to the transgression. The wide-spread gas hydrate occurrence beneath permafrost has implications on the region including drilling hazards associated with the presence of free gas, possible overpressure, lateral migration of fluids and expulsion at the seafloor. In contrast to the permafrost-associated gas hydrates, a deep-water marine BSR was also identified on MCS profiles. The MCS data show a polarity-reversed seismic reflection associated with a low-velocity zone beneath it. The seismic data coverage in the southern Beaufort Sea shows that the deep-water marine BSR is not uniformly present across the entire region. The regional discrepancy of the BSR occurrence between the US Alaska portion and the Mackenzie Delta region may be a result of high sedimentation rates expected for the central Mackenzie delta and high abundance of mass-transport deposits that prohibit gas to accumulate within and beneath the gas hydrate stability zone.
2018015691 Daout, Simon (Université Grenoble-Alpes, Institut des Sciences de la Terre, Grenoble, France); Doin, Marie-Pierre; Peltzer, Gilles; Socquet, Anne and Lasserre, Cécile. Large-scale InSAR monitoring of permafrost freeze-thaw cycles on the Tibetan Plateau: Geophysical Research Letters, 44(2), p. 901-909, illus. incl. sketch map, 34 ref., January 28, 2017.
Multitemporal interferometric synthetic aperture radar (InSAR) observations are used to characterize spatial variations of the permafrost active layer and its temporal evolution in Northwestern Tibet. We develop a method to enhance InSAR performances for such difficult terrain conditions and construct an 8 year timeline of the surface deformation over a 60,000 km2 area. The ground movement induced by the active layer's response to climate forcing is limited to Cenozoic sedimentary basins and is spatially variable in both its seasonal amplitude (2.5-12 mm) and multiannual trend (-2 to 3 mm/yr). A degree-day integrated model adjusted to the data indicates that subsidence occurs when the surface temperature exceeds zero (May to October) over areas where seasonal movements are large (>8 mm). The period of subsidence is delayed by 1-2 months over areas where smaller seasonal movements are observed, suggesting an unsaturated soil where water occurs in the deeper part of the active layer. Abstract Copyright (2017), . American Geophysical Union. All Rights Reserved.
2018012140 Elvert, Marcus (University of Bremen, Center for Marine Environmental Sciences, Bremen, Germany); Pohlman, John W.; Becker, Kevin W.; Gaglioti, Benjamin; Hinrichs, Kai-Uwe and Wooller, Matthew J. Methane turnover and environmental change from Holocene lipid biomarker records in a thermokarst lake in Arctic Alaska: Holocene, 26(11), p. 1766-1777, illus. incl. 4 tables, 83 ref., November 1, 2016.
Arctic lakes and wetlands contribute a substantial amount of methane to the contemporary atmosphere, yet profound knowledge gaps remain regarding the intensity and climatic control of past methane emissions from this source. In this study, we reconstruct methane turnover and environmental conditions, including estimates of mean annual and summer temperature, from a thermokarst lake (Lake Qalluuraq) on the Arctic Coastal Plain of northern Alaska for the Holocene by using source-specific lipid biomarkers preserved in a radiocarbon-dated sediment core. Our results document a more prominent role for methane in the carbon cycle when the lake basin was an emergent fen habitat between ~12,300 and ~10,000 cal yr BP, a time period closely coinciding with the Holocene Thermal Maximum (HTM) in North Alaska. Enhanced methane turnover was stimulated by relatively warm temperatures, increased moisture, nutrient supply, and primary productivity. After ~10,000 cal yr BP, a thermokarst lake with abundant submerged mosses evolved, and through the mid-Holocene temperatures were approximately 3°C cooler. Under these conditions, organic matter decomposition was attenuated, which facilitated the accumulation of submerged mosses within a shallower Lake Qalluuraq. Reduced methane assimilation into biomass during the mid-Holocene suggests that thermokarst lakes are carbon sinks during cold periods. In the late-Holocene from ~2700 cal yr BP to the most recent time, however, temperatures and carbon deposition rose and methane oxidation intensified, indicating that more rapid organic matter decomposition and enhanced methane production could amplify climate feedback via potential methane emissions in the future.
2018017653 Banville, David Roy (Université Laval, Département de Géologie et de Génie Géologique, Quebec, QC, Canada); Fortier, Richard and Dupuis, Christian. Objective interpretation of induced polarization tomography using a quantitative approach for the investigation of periglacial environments: Journal of Applied Geophysics, 130, p. 218-233, illus. incl. sects., 2 tables, geol. sketch map, 49 ref., July 2016.
The objective interpretation of induced polarization tomography for applications in periglacial environments is sometimes challenging using smoothness-regularized least square inversion because strong resistivity contrasts are often present. Ambiguities arise from the regularization process which smooths the contrast between layers and from artifacts created by the inversion. In periglacial environments, where frozen and thawed ground can coexist with large resistivity contrasts, such artefacts are often found in the models of electrical resistivity. To assess reliable cryohydrogeological models from the inversion of induced polarization tomography, quantitative interpretation criteria are needed. The present work describes a methodology based on forward-inverse modeling to build a cryohydrogeological model from induced polarization data and prior information using the resistivity and chargeability gradients to map transitions between adjacent layers. This methodology is tested on field-data acquired over a coarse grained aquifer within a glaciomarine deposit and ice-rich permafrost mounds within marine sediments. Delineation of the permafrost base is achieved despite the presence of an inversion artefact. The results of the interpretation are used to further constrain the inversion in order to map the ice-content based on the resistivity model and an empirical relationship. The proposed methodology provides a way to extract quantitative information even in difficult environmental settings.
2018012044 Grosse, Guido (Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany); Goetz, Scott J.; McGuire, A. David; Romanovsky, Vladimir E. and Schuur, Edward A. G. Changing permafrost in a warming world and feedbacks to the Earth system: Environmental Research Letters, 11(4), Paper no. 040201, 1 table, sketch map, 48 ref., April 2016.
2018012045 Kharuk, Viacheslav I. (Sukachev Forest Institute, Krasnoyarsk, Russian Federation); Shushpanov, Alexandr S.; Im, Sergei T. and Ranson, Kenneth J. Climate-induced landsliding within the larch dominant permafrost zone of central Siberia: Environmental Research Letters, 11(4), Paper no. 045004, illus. incl. 3 tables, sketch map, 42 ref., April 2016. Includes appendix.
2018011806 Abbott, Benjamin W. (Université de Rennes I, Observatoire des Sciences de l'Univers, Rennes, France); Jones, Jeremy B.; Schuur, Edward A. G.; Chapin, F. Stuart, III; Bowden, William B.; Bret-Harte, M. Syndonia; Epstein, Howard E.; Flannigan, Michael D.; Harms, Tamara K.; Hollingsworth, Teresa N.; Mack, Michelle C.; McGuire, A. David; Natali, Susan M.; Rocha, Adrian V.; Tank, Suzanne E.; Turetsky, Merritt R.; Vonk, Jorien E.; Wickland, Kimberly P.; Aiken, George R.; Alexander, Heather D.; Amon, Rainer M. W.; Benscoter, Brian W.; Bergeron, Yves; Bishop, Kevin; Blarquez, Olivier; Bond-Lamberty, Ben; Breen, Amy L.; Buffam, Ishi; Cai Yihua; Carcaillet, Christopher; Carey, Sean K.; Chen, Jing M.; Chen, Han Y. H.; Christensen, Torben R.; Cooper, Lee W.; Cornelissen, J. Hans C.; de Groot, William J.; DeLuca, Thomas H.; Dorrepaal, Ellen; Fetcher, Ned; Finlay, Jacques C.; Forbes, Bruce C.; French, Nancy H. F.; Gauthier, Sylvie; Girardin, Martin P.; Goetz, Scott J.; Goldammer, Johann G.; Gough, Laura; Grogan, Paul; Guo, Laodong; Higuera, Philip E.; Hinzman, Larry; Hu, Feng Sheng; Hugelius, Gustaf; Jafarov, Elchin E.; Jandt, Randi; Johnstone, Jill F.; Karlsson, Jan; Kasischke, Eric S.; Kattner, Gerhard; Kelly, Ryan; Keuper, Frida; Kling, George W.; Kortelainen, Pirkko; Kouki, Jari; Kuhry, Peter; Laudon, Hjalmar; Laurion, Isabelle; Macdonald, Robie W.; Mann, Paul J.; Martikainen, Pertti J.; McClelland, James W.; Molau, Ulf; Oberbauer, Steven F.; Olefeldt, David; Paré, David; Parisien, Marc-André; Payette, Serge; Peng, Changhui; Pokrovsky, Oleg S.; Rastetter, Edward B.; Raymond, Peter A.; Raynolds, Martha K.; Rein, Guillermo; Reynolds, James F.; Robards, Martin; Rogers, Brendan M.; Schädel, Christina; Schaefer, Kevin; Schmidt, Inger K.; Shvidenko, Anatoly; Sky, Jasper; Spencer, Robert G. M.; Starr, Gregory; Striegl, Robert G.; Teisserenc, Roman; Tranvik, Lars J.; Virtanen, Tarmo; Welker, Jeffrey M. and Zimov, Sergei. Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire; an expert assessment: Environmental Research Letters, 11(3), Paper no. 034014, illus. incl. 3 tables, 86 ref., March 2016.
2018011819 Pavlova, N. A. (Russian Academy of Sciences, Melnikov Permafrost Institute, Siberian Branch, Yakutsk, Russian Federation); Kolesnikov, A. B.; Efremov, V. S. and Shepelev, V. V. Groundwater chemistry in intrapermafrost taliks in central Yakutia: Water Resources, 43(2), p. 353-363, illus. incl. 2 tables, sketch map, 19 ref., March 2016. Original Russian Text: Pavlova, N. A., Kolesnikov, A. B., Efremov, V. S., Shepelev, V. V., published in Vodnye Resursy, Vol. 43, No. 2, p. 216-227, 1016.
An intrapermafrost aquifer system, which is widespread in the sand deposits of bestyakhskaya terrace of the Lena R. (Central Yakutia), is characterized by generalized data of many-year studies of its groundwater chemistry. The groundwater discharges onto land surface through high-yield springs. The largest such source forms the Ulakhan-Taryn Creek with a mean many-year yield of 20 740 m3/day. The results of generalization were used to show the chemistry of intrapermafrost water to be stable at both many-year and annual scales, to characterize the hydraulic interaction of intrapermafrost water with suprapermafrost and subpermafrost water, to assess the spatial variations of groundwater resources in the intrapermafrost aquifer from the head-formation to the discharge domain. The results of the study are of importance for solving the problem of centralized drinking water supply to large populated localities in the Central Yakutia, including Yakutsk City. Copyright 2016 Pleiades Publishing, Ltd.
2018011807 Segal, Rebecca A. (University of Victoria, School of Environmental Studies, Victoria, BC, Canada); Lantz, Trevor C. and Kokelj, Steven V. Acceleration of thaw slump activity in glaciated landscapes of the Western Canadian Arctic: Environmental Research Letters, 11(3), Paper no. 034025, illus. incl. 2 tables, sketch map, 79 ref., March 2016.
2018015096 Hou Yandong (Chinese Academy of Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Lanzhou, China); Wu Qingbai; Liu Yongzhi; Zhang Zhongqiong and Gao Siru. The thermal effect of strengthening measures in an insulated embankment in a permafrost region: Cold Regions Science and Technology, 116, p. 49-55, illus. incl. 5 tables, sketch map, August 2015. Based on Publisher-supplied data.
An embankment with heat insulation can only retard a rise in temperature or the thawing of permafrost, and the thermal stability of the embankment cannot be maintained under global warming conditions. Therefore, strengthening measures are required to ensure embankment stability. Based on in-situ observational data from the Qinghai-Xizang Railway in Beiluhe, variations in the thermal regime under a thermally insulated embankment after the implementation of strengthening measures were analysed. The results show that the strengthening measure of thermosyphon installation can play an effective role in the embankment cooling process; however, no protective effect of the spall rock revetment was observed. The shallow mean annual maximum temperature in the upper 0.5 m of soil decreased from 2.2 to 0 °C with an average of 1.8 °C, appearing as a striking "cold energy accumulation" process which predominantly results from thermosyphons and heat insulation material, after the strengthening measures were implemented. Meanwhile, the permafrost table under the embankment appeared as a "second rising process", ranging from 0.90 m for DK1139 + 670 to 2.56 m for DK1139 + 780, with an average of 1.66 m. The "sunny-shady slope effect" was not well controlled after the implementation of the strengthening measures under the embankment with thermal insulation. However, the difference in temperature between the ground and underlying permafrost table, under the left and right shoulder of the embankment, gradually decreased. Besides, thermal influence of the embankment to the surrounding permafrost in the deep layer is observed to be eliminated after the implementation of the strengthening measures. Abstract Copyright (2015) Elsevier, B.V.
2018015083 Yu Fan (Chinese Academy of Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Lanzhou, China); Qi Jilin; Yao Xiaoliang and Liu Yongzhi. Comparison of permafrost degradation under natural ground surfaces and embankments of the Qinghai-Tibet Highway: Cold Regions Science and Technology, 114, p. 1-8, illus., June 2015. Based on Publisher-supplied data.
Permafrost under road embankments often degrades more seriously than that under natural ground surfaces due to the influences of both climate warming and road embankment. In a companion paper, we analyzed the states of permafrost degradation under road embankments in the five typical regions along the Qinghai-Tibet Highway (Yu et al., 2013a). In this paper, the states of permafrost degradation under natural ground surfaces, near the road embankments, are analyzed based on up to 15 years of in-situ geothermal data, while that under road embankments are also further analyzed. On this basis, the states of permafrost degradation and related processes are compared between the natural ground surfaces and road embankments. Possible influences of climate warming and road embankment on permafrost degradation are discussed. The results show different characteristics of permafrost degradation under natural ground surfaces and road embankments. The contributions of climate warming and road embankment on the thermal regime of permafrost may vary during the process of permafrost degradation. Abstract Copyright (2015) Elsevier, B.V.
2018015138 Beck, I. (Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Potsdam, Germany); Ludwig, R.; Bernier, M.; Strozzi, T. and Boike, J. Vertical movements of frost mounds in subarctic permafrost regions analyzed using geodetic survey and satellite interferometry: Earth Surface Dynamics, 3(3), p. 409-421, illus. incl. 4 tables, sketch maps, 70 ref., 2015.
Permafrost-affected soils cover about 40-45% of Canada. The environment in such areas, especially those located within the discontinuous permafrost zone, has been impacted more than any other by recorded climatic changes. A number of changes, such as surface subsidence and the degradation of frost mounds due to permafrost thawing, have already been observed at many locations. We surveyed three frost mounds (lithalsas) in the subarctic, close to Umiujaq in northern Quebec, using high-precision differential global positioning system (d-GPS) technology during field visits in 2009, 2010 and 2011, thus obtaining detailed information on their responses to the freezing and thawing that occur during the course of the annual temperature cycle. Seasonal pulsations were detected in the frost mounds, and these responses were shown to vary with their state of degradation and the land cover. The most degraded lithalsa showed a maximum amplitude of vertical movement (either up or down) between winter (freezing) and summer (thawing) of 0.19 ± 0.09 m over the study period, while for the least degraded lithalsa this figure was far greater (1.24 ± 0.47 m). Records from areas with little or no vegetation showed far less average vertical movement over the study period (0.17 ± 0.03 m) than those with prostrate shrubs (0.56 ± 0.02 m), suggesting an influence from the land cover. A differential interferometric synthetic aperture radar (D-InSAR) analysis was also completed over the lithalsas using selected TerraSAR-X images acquired from April to October 2009 and from March to October 2010, with a repeat cycle of 11 days. Interferograms with baselines shorter than 200 m were computed revealing a generally very low interferometric coherence, restricting the quantification of vertical movements of the lithalsas. Vertical surface movements of the order of a few centimeters were recorded in the vicinity of Umiujaq.
2018009728 Sun Guangyou (Jilin University, Changchun, China). A re-examination of the tundra of the Tibetan Plateau; determination of geographic polarity for the third pole of Earth: Diqiu Kexue yu Huanjing Xuebao = Journal of Earth Sciences and Environment, 35(3), p. 97-105, (Chinese) (English sum.), illus. incl. 4 tables, sketch map, 40 ref., September 2013.
Understanding the tundra of the Tibetan Plateau is important for defining Earth's third pole (height) as geographic, creating a basic problem for global geographic science. A definition of tundra is proposed, as well as an index for a tundra environment consisting of five factors. The five factors are: mean July temperature is 0°C-10°C; a periglacial environment located in ice cover or on a glacier's periphery, with significant frost; permafrost is present; the soil has frost; and there are no trees. The region with average July temperatures of 0°C-10°C is about 50.4% (129.64´104 km2) of the Tibetan Plateau; there is a wide distribution of valley glaciers, and a modern periglacial environment is typical for the region; the region's permafrost area is 72.05% of the Tibetan Plateau, where frozen soil and tundra soil have developed; and the area is treeless as the altitude is above the tree line, though there is small brush, grass, and moss. Therefore, there is a tundra environment on the Tibetan Plateau. Many plants in marshes are unique; when a wide frost peat mound combines with cellular soil, marsh tundra develops. Hill tundra develops around the plateau, and a plateau tundra developed in the middle. The Tibetan Plateau is characteristically highland, so there is no distinct highland tundra and it reflects the tundra diversity. It is incorrect to state that tundra only exists in China's Changbai Mountains, Altai Mountains, and Tien Shan; however, the Tibetan Plateau is the southern edge of China's tundra. The discovery of tundra on the Tibetan Plateau can confirm the geographic polarity for Earth's third pole, and has important significance for a deeper understanding of the plateau environment.
2018014741 Drozdov, A. V. (Alrosa, Institut Yakutniproalmaz, Yakutsk, Russian Federation) and Popov, V. F. Formirovaniye podzemnykh rezervuarov v kriolitozone Sibirskoy platformy, prigodnykh dlya udaleniya zhidkikh toksichnykh otkhodov [Developing underground reservoirs suitable for the storage of liquid toxic waste in the permafrost zone of the Siberian Platform]: Otechestvennaya Geologiya, 2013(2), p. 57-62 (English sum.), illus. incl. sketch map, 8 ref., April 2013.
This paper covers paleoclimatic and structural-tectonic conditions of forming favorable cryohydrogeological structures (underground reservoirs) for burying industrial effluents at the Siberian Platform. Basic capacity of natural reservoirs for industrial effluents pumping in is confined to regional tectonic disturbed intervals of the cryolithozone, which possess increased filtering-capacitance features of ores.
2018010008 Neradovskiy, L. G. K voprosu o stokhasticheskoy prirode signalov georadiolokatsii [Stochastic nature of ground-penetrating radar signals]: Geofizika (Moscow), 2013(2), p. 58-62 (English sum.), 3 ref., 2013. Based on Publisher-supplied data.
Based on the use of various GPR systems in the Yakutian permafrost region, this study has demonstrated that ground penetrating radar signals are of stochastic nature. This fact should be taken into account during data acquisition and processing stages, considering single GPR signal records as special samples from the ensemble of signals in the random process generating a field of various radio reflections from flat interfaces and irregularities in the soil and rock masses. Such an approach allows the use of one-time GPR signal records in determining the geometry of interfaces in horizontally layered sections, as is the common case in GPR practice. However, in studies of the structure of complex sections, as well as the state and properties of soils and rocks, especially those in frozen condition, one-time GPR signal records are fundamentally incapable of providing reliable interpretations and hence trustworthy results.
2018013283 Solomatin, V. I. Fizika i geografiya podzemnogo oledeneniya; uchebnoye posobiye dlya vuzov [Physics and geography of ground ice; a college textbook]: Geo, Novosibirsk, Russian Federation, 346 p. (English sum.), illus. incl. 21 tables, sects., sketch maps, 273 ref., 2013. ISBN: 9785906284358.
The most crucial materials and ideas of the physical and spatiotemporal laws of underground ice formation and underground glaciation development, including the author's results of long-term field and laboratory investigations, are collected, analyzed, and generalized. Theoretical and experimental studies of the physical processes of ice formation in the permafrost zone are used as a base for structural reconstructions of the thermal, facies and other conditions and of the factors responsible for different genetic types of underground ice. The most important result of the author's investigations is the theory of buried glacial ice in the permafrost zone, which fundamentally changes the understanding of the structure and paleogeography of underground glaciation, as well as its place in the Earth's cryosphere. A consequent analysis of the natural and experimental data on all scales and for all structural levels of underground ice formation (from the microworld of water phase transitions to the macroworld of the spatial and temporal evolution of geologic and geographic modifications of underground glaciation) permits the development of a genetic classification of underground ice and a general pattern of the zonal-climatic structure of underground glaciation.
2018013913 Bandler, Aaron J. Geophysical constraints on critical zone architecture and subsurface hydrology of opposing montane hillslopes: 48 p., illus. incl. 3 tables, geol. sketch maps, 70 ref., Master's, 2016, Colorado School of Mines, Golden, CO. Includes appendices.
We investigate the relationship between slope aspect, subsurface hydrology, and critical zone (CZ) structure in a montane watershed by examining the orientations of foliation and fracturing and thicknesses of weathered material on north- and south-facing aspects. Weathering models predict that north-facing slopes will have thicker and more porous saprolite due to colder, wetter conditions, which exacerbate frost damage and weathering along open fractures. Using borehole imaging and seismic refraction, we compare the seismic velocity and anisotropy of north- and south-facing slopes with the orientation of fracturing. Fracturing occurs in the same dominant orientations across slopes, but the north-facing slope has more developed and slightly thicker soil as predicted, while the south-facing slope has thicker and more intact saprolite that is highly anisotropic in the direction of fracturing. Our data support hypotheses that subsurface flow is matrix-driven on north-facing slopes and preferential on south-facing slopes. We attribute thicker saprolite on south-facing slopes to heterogeneity induced by competition between infiltration, topographic stress, and permafrost during Pleistocene glaciation. We provide new constraints on subsurface architecture to inform future models of CZ evolution.
2018012823 Abakumov, Evgeny (Saint-Petersburg State University, Biology and Soil Science, Applied Ecology, Saint-Petersburg, Russian Federation). Stabilization of polar soils organic matter; insights from 13-C NMR and ESR spectroscopy [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-2141, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018012705 Ashastina, Kseniia (Senckenberg Research Institute, Station of Quaternary Palaeontology, Weimar, Germany); Kienast, Frank; Römermann, Christine; Kuzmina, Svetlana; Diekmann, Bernhard and Schirrmeister, Lutz. The Batagay permafrost mega thaw slump; an environmental archive of the Late Pleistocene continental climate [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-959, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018012724 Elagina, Nelly (Russian Academy of Sciences, Institute of Geography, Department of Glaciology, Moscow, Russian Federation); Kutuzov, Stanislav; Chernov, Robert; Lavrentiev, Ivan; Vasilyeva, Tatiana; Mavlyudov, Bulat and Kudikov, Arseny. Establishing mass balance observation at Austre Gronfjordbreen, Nordenskjold land, Svalbard [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1005, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018014161 Evgrafova, Alevtina (University of Koblenz-Landau, Geography Department, Koblenz, Germany); Kühnel, Anna; Bogner, Christina; Haase, Ina; Shibistova, Olga; Guggenberger, Georg; Tananaev, Nikita; Sauheitl, Leopold and Spielvogel, Sandra. Visible-near infrared spectroscopy as a tool to improve mapping of soil properties [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract 851, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016547 Fritz, Michael (Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Periglacial Research, Potsdam, Germany) and Lantuit, Hugues. Collapsing permafrost coasts in the Arctic [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-3464, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016209 Gries, Philipp (Eberhard Karls University Tübingen, Department of Geosciences, Soil Science and Geomorphology, Tubingen, Germany); Wagner, Julia; Kandolf, Lorenz; Henkner, Jessica; Kühn, Peter; Scholten, Thomas and Schmidt, Karsten. Investigations on soil organic carbon stocks and active layer thickness in West Greenland [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1304, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016480 Grzyb, Jaroslaw (Polish Academy of Sciences, Insitiute of Geophysics, Warsaw, Poland) and Majdanski, Mariusz. Seismic imaging of post glacial sediments; technical problems and solutions [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-3292, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016066 Hrbacek, Filip (Masaryk University, Department of Geography, Brno, Czech Republic); Knazkova, Michaela; Nyvlt, Daniel; Laska, Kamil; Mueller, Carsten W. and Ondruch, Jakub. Monitoring of active layer thermal regime and depth on CALM-S site, James Ross Island, Eastern Antarctic Peninsula [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-707, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016511 Khomutov, Artem (Russian Academy of Sciences, Siberian Branch, Earth Cryosphere Institute, Tyumen, Russian Federation); Leibman, Marina; Dvornikov, Yury and Aref'yev, Stanislav. Results of the first field visit to Antipayutinsky gas-emission crater (AntGEC) on Gydan Peninsula, Russia in 2016 [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-3371, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016079 Kramshoj, Magnus (University of Copenhagen, Department of Biology, Copenhagen, Denmark); Holst, Thomas; Albers, Christian; Holzinger, Robert; Elberling, Bo and Rinnan, Riikka. Microbial uptake of biogenic volatile organic compounds released from thawing permafrost [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-732, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016116 Kula, Damian (University of Silesia, Katowice, Poland) and Olszewska, Dorota. Seasonal variability of horizontal to vertical spectral ratio in polar regions [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1071, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016246 Myshonkov, Alexander (Moscow State University, Soil Science Faculty, Moscow, Russian Federation); Matyshak, George and Petrzhik, Natalia. Cryogenic disturbance and its impact on soils of frost boil ecosystems of Taz peninsula, West Siberia [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1522, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018012735 Nesterova, Natalia (St. Petersburg State University, Institute of Geosciences, Russian Federation); Makarieva, Olga and Lebedeva, Lyudmila. Hydrological modelling over different scales on the edge of the permafrost zone; approaching model realism based on experimentalists' knowledge [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1047, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016165 Ogneva, Olga (Lomonosov Moscow State University, Department of Soil Science, Moscow, Russian Federation); Matyshak, George and Tarkhov, Matvey. Frozen peatlands; carbon store and the climate change [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1207, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016370 Olefeldt, David (University of Alberta, Renewable Resources, Edmonton, AB, Canada); Heffernan, William; Gibson, Carolyn; Burd, Katheryn and Estop-Aragones, Cristian. Interactive effects of wildfire and permafrost thaw on peatland carbon cycling [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-3032, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016084 Orlov, Timofey (Russian Academy of Sciences, Sergeev Institute of Environmental Geoscience, Russian Federation); Sadkov, Sergey; Panchenko, Evgeniy and Zverev, Andrey. Stochastic modelling for lake thermokarst and peatland patterns in permafrost and near permafrost zones [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-743, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016268 Petrzhik, Nataliya (Moscow State University, Faculty of Soil Science, Russian Federation); Matyshak, George; Myshonkov, Alexander and Petrov, Dmitry. Arctic ecosystem reaction on permafrost melting as a result of 40 years anthropogenic impact [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1560, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018012881 Scherler, Dirk (German Research Centre for Geosciences, Potsdam, Germany). Geomorphic feedbacks between hillslopes and valley glaciers; implications for climate reconstructions and landscape evolution [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-2286, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018012745 Siewert, Matthias (Stockholm University, Department of Physical Geography, Stockholm, Sweden) and Hugelius, Gustaf. High-resolution mapping and spatial variability of soil organic carbon storage of permafrost-affected soils [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1332, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016135 Sperlich, Peter (University of Copenhagen, Centre for Ice and Climate, Copenhagen, Denmark); Schaefer, Hinrich; Fletcher, Sara Mikaloff; Guillevic, Myriam; Lassey, Keith; Sapart, Célia; Röckmann, Thomas and Blunier, Thomas. Carbon isotope ratios suggest no additional methane from boreal wetlands during the rapid Greenland Interstadial 21.2 [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1122, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018016326 Uxa, Tomas (Charles University, Department of Physical Geography and Geoecology, Prague, Czech Republic) and Mida, Peter. Ground surface thermal regime of rock glaciers in the High Tatra Mts., Slovakia [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-1740, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018014118 Voigt, Carolina (University of Eastern Finland, Department of Environmental and Biological Sciences, Kuopio, Finland); Lamprecht, Richard E.; Marushchak, Maija E.; Lind, Saara E.; Novakovskiy, Alexander; Aurela, Mika; Martikainen, Pertti J. and Biasi, Christina. Enhanced greenhouse gas emissions from the Arctic with experimental warming [abstr.]: in European Geosciences Union general assembly 2017, Geophysical Research Abstracts, 19, Abstract EGU2017-495, 2017. Meeting: European Geosciences Union general assembly 2017, April 23-28, 2017, Vienna, Austria.
2018015279 Dadfar, B. (Western University, Department of Civil and Environmental Engineering, London, ON, Canada); El Naggar, M. H. and Nastev, M. Seismic behavior of buried energy pipelines in northern permafrost regions: in 6ICEGE; 6th international conference on Earthquake geotechnical engineering; proceedings (Cubrinovski, Misko, chairperson; et al.), New Zealand Geotechnical Society, New Zealand, 8 p., illus. incl. 1 table, 7 ref., 2015. Meeting: 6th international conference on Earthquake geotechnical engineering, Nov. 1-4, 2015, Christchurch, New Zealand. Paper no. 598.

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