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2021 year, number 5
V.G. Cheverev1, A.V. Brushkov1, S.A. Polovkov2, E.A. Pokrovskay2, E.V. Safronov1
1Lomonosov Moscow State University, Leninskie Gory 1, Moscow, 119991, Russia 2Scientific Research Institute of Pipeline Transport, Sevastopolsky pr. 47a, Moscow, 117186, Russia
Keywords: analytical review, mechanism of cryogenic migration, frost heaving of soils
Abstract >>
A retrospective analysis of the results of studies of the mechanism of water migration in freezing soils was carried out on the basis of an analysis of about 160 scientific publications by Russian and 100 foreign authors. For the analysis, articles, monographs, dissertations, patents, conference proceedings and scientific reports were used. The main ones are given in the list of references. Special attention is paid to the key aspects of the formation of understanding of the driving forces of cryogenic migration (moisture transfer) in freezing soils. This analysis is necessary for the correct physical formulation of the mathematical model of the process of frost heaving of freezing soils.
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A.A. Svetlakov1, E.A. Kozyreva1, D.O. Sergeev2
1Institute of the Earth’s Crust, SB RAS, Lermontov str. 128, Irkutsk, 664033, Russia 2Sergeev Institute of Environmental Geoscience, RAS, Ulansky per. 13, bldg. 2, Moscow, 101000, Russia
Keywords: permafrost, temperature regime, seasonally thawed and seasonally frozen layer
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The paper analyzes the current temperature state of frozen and thaw soils in the Baikal region (Olkhon Island). It has been demonstrated that the current trend in soil temperature is directly related to climate changes and to the increase in the atmospheric air temperature. Permafrost within Olkhon Island is significantly transformed: the processes in soils are aimed at the degradation of frozen strata.
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V.V. Selyuzhenok
Zubov State Oceanographic Institute, Kropotkinskij per. 6, Moscow, 119034, Russia
Keywords: landfast sea ice, sea ice, stamukhi
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The paper presents the data on maximal extent of the East Siberian fast ice and its variability based on Arctic and Antarctic Research Institute operational sea ice chart for the period from 1999 to 2019. The maximal fast ice extent were compared to the ERA5 reanalysis local winds. The analysis of the maximal landfast ice variability showed no statistically significant changes between 1999 and 2019. Two typical configurations of fast ice edge were revealed for the winter month characterized by the maximal fast ice extent. In some seasons fast ice development stops once the edges reaches 20 m depth, while in other season the fast ice edges advances to 30 m depth. The maximal fast ice extent is reached during the seasons with prevailing northerly and north-easterly winds. The onshore wind favours sea ice deformation and grounding at the seaward fast ice edge.
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E.P. Rets1, D.A. Petrakov2, E.V. Belozerov1, A.M. Shpuntova2
1Water Problems Institute, RAS, Gubkina str. 3, Moscow, 119333, Russia 2Lomonosov Moscow State University, Leninskie Gory 1, Moscow, 119991, Russia
Keywords: mass balance modelling, glaciers, Tien Shan, A-Melt model
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As the direct measurements for the mass balance estimation can be applied only for a limited number of glaciers, alternative methods of estimation need to be developed. One of the most promising approaches is physically-based modelling, that is now being applied globally. In this study the mass balance of the Sary-Tor valley glacier was reconstructed for the period of 2003-2016. Originally developed for the North Caucasus A-Melt model was modified to fit the conditions of continental glaciers. A block of snowpack processes was added to the model, including: head conductivity in the snowpack and in the active layer, water filtration in the snowpack and firn, congelation and regelation. The modelling results were verified using: 1) direct measurements on the ablation stakes net; 2) mass balance estimation according to geodetic method. The calibration parameters are compared to their measured values. Contrasting modeled mass-balance components for 2003-2016 and measured in 1985-1989 provided possibility to reveal climatically induced change of the Sary-Tor glacier dynamics.
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V.V. Elsakov, D.A. Kaverin, V.M. Shchanov
Institute of Biology, Kommunisticheskya str. 28, Syktyvkar, 167982, Russia
Keywords: differential radar interferometry, piedmont landscapes of the Polar Ural, ground subsidence and heave
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Interferometric pairs of ALOS PALSAR dataset (2007-2010) were used to estimate the seasonal and long-term variations in the ground surface height in the piedmont of the Polar Ural, the far northeast of European Russia. The obtained results were validated by ground-truth measurements at the CALM R2 site (the site of monitoring the thickness of the active layer). The values and amplitude of ground surface height variations obtained from the satellite imagery were lower compared to field measurements. The sites under study were classified in two conditional groups: more drained sites (confined often to the upper parts of the moraine ridges) and sites with higher moisture content in the soil (lower parts of the slopes). This classification was based on the intensity of seasonal changes in the height of ground surface during the vegetation period of 2007. Significant correlations between the compared in situ and remote sensing-based measurements were established for these groups. The convergence of the results increased with a greater number of in situ measurements inside the pixel of the satellite image. The greatest differences in the magnitude of changes in the height of ground surface were reported in years marked by contrasting weather conditions (2007 and 2010). Ground surface subsidence was reported to be greater (up to 1.5-4.5 cm) during the colder and wetter vegetation period of 2010, and less pronounced in a drier and warmer season of 2007 (0.0-3.0 cm) within tundra zones of the Pechora Lowland. A summer ground surface heave was noted (up to 2-3 cm) in sites with moraines deposits in the piedmont plains for the whole period of observations.
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D.E. Edemsky1, V.E. Tumskoy2, A.N. Ovsyuchenko3
1Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation, RAS, Kaluzhskoe hwy 4, Moscow, Troitsk, 108840, Russia 2Melnikov Permafrost Institute, SB RAS, Merzlotnaya str. 36, Yakutsk, 677010, Russia 3Schmidt Institute of Physics of the Earth, RAS, B. Gruzinskaya str. 10, bldg. 1, Moscow, 123242, Russia
Keywords: ground-penetration radar, polygonal microrelief, spectrum of waveforms, hodograph diagram, Taimyr Peninsula, Kotelny Island
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This article analyses the results of Loza-B georadar sounding of the upper part of the permanently frozen ground section in the area of polygonal microrelief development. These investigations took place on the eastern coast of the Taymyr Peninsula and on the western coast of Kotelny Island (New Siberian Islands). The polygonal microrelief is at the descend stage of development at both sites, so the ground-penetration radar profiles were scanned across the flat and high-centered central parts of the polygons. The results allowed us to determine some peculiarities of ground-penetration radar profiles for polygons with different types of surfaces, composed mainly of sand-gravel deposits. Typical ground-penetration radar complexes corresponding to the central parts of the polygons and deposits overlapping thawed ice wedges were identified. The possibility of using the spectrum of waveforms to interpret results was shown, velocities of electromagnetic wave propagation in the studied deposits were determined. Ice wedges and pseudomorphs after them were not reliably identified, but areas of their possible location were.
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