Abstract: The study focuses on improving the accuracy of geophysical investigations of anthropogenic metallic pollution using digital elevation models (DEMs). The methodology was tested at the Norilsk site, located in close proximity to the slag heaps of the nickel plant, based on DEM data obtained through unmanned aerial vehicles (UAVs) to conduct a detailed geomorphological analysis of the area. Geophysical methods such as the natural field (NF) method and frequency sounding were also used to identify zones of potential metallic pollution, as well as the characteristics and spatial positions of predicted permafrost layers. The main emphasis is on the advantages of integrating geophysical methods with DEMs and derived cartographic materials to improve the accuracy and reliability of surface metallic pollution detection and mapping, considering the geocryological situation within the study area. Geophysical methods of natural field (NF) and frequency sounding were employed to determine the geoelectrical properties of the study area. Reconnaissance surveys and flight missions were conducted to create the digital elevation model and orthoimage, and a surface water runoff map was developed based on the generated rasters and their interpretation. Based on the obtained geophysical data, zones of possible metallic pollution spread from the slag heaps were identified, which were confirmed through DEM analysis by the geomorphology of the study site. The distribution of specific electrical resistance fields was also interpreted in consideration of the collected data and validated through borehole drilling. It is worth noting that the integrated approach helped reveal the need to revise the interpretation plan, as only through the analysis of the nature and intensity of metallic pollution could the abnormally low resistance values in areas far from thermokarst lakes, with relatively shallow permafrost depths, be explained. Additionally, it became possible to qualitatively assess the zones of dust material accumulation.

Keywords: Spoil tip, Slag heap, Electrical resistivity, DEM, UAV, Natural field method, Frequency sounding, Geophysical study, Norilsk, Geocryological structure

Abstract: The subject of research is natural and man-made kurums (blocky accumulations of rocks). The purpose of the work was to analyze the main literary sources, in which the results of research on the formation of the thermal regime of rock dumps (kurums) were published. The retrospective period of the research extends for more than 50 years. Domestic and foreign sources of information are considered. The most representative ones have been selected for analysis, in which the results of research with theoretical value and practical significance have been published. The analysis showed that on many important aspects of the formation of the thermal regime of natural and man-made kurums, all the authors of studies conducted in different regions and at different time periods, independently of each other, came to the same conclusions. This indicates the reliability and objectivity of the results obtained. An analytical review of scientific articles was used as a research method, in which research materials on the formation of the thermal regime of both the kurums themselves and their soil bases were published. The kurums of the permafrost and island permafrost zones are considered. An analytical review of literary sources containing theoretical and practical results of research on the formation of the thermal regime of natural and man-made kurums is carried out. The results of the analysis allow us to draw the following main conclusions. 1. Any types of natural and man-made kurums lead to progressive cooling of the base on which they are located. 2. When interacting with the rock base, the technogenic kurum works as an active thermal protection, changing its thermal resistance during the annual cycle. 3. When modeling the process of thermal interaction of technogenic kurum, it is quite acceptable to consider the kurum as a heat-protective layer, the thermal resistance of which depends on the effective coefficient of thermal conductivity, which changes its value when the sign of atmospheric air temperature changes. Based on the analysis of the results of the published works, conclusions are drawn about the possibility of a number of simplifications in the construction of computational models for forecasting and controlling the thermal regime of frozen bases of technogenic kurums.

Keywords: modeling, forecast, rock formations, source, literature, analyze, kurums, thermal mode, cryolithozone, the ground

Abstract: The article analyses production volumes and consumption patterns of heat and electricity in the Arkhangelsk region, based on statistical and corporate data. The work reveals that, despite the fact that the number of generation facilities operating on the base of local biofuels is rapidly increasing, the region remains highly dependent on hydrocarbon, mainly imported from the other regions. Currently, some two-third of all boiler houses and a significant part of power plants use local wood fuel, but the transition to biofuels primarily affects low-capacity generating facilities. As a result, the total share of biofuels in energy production in the region is no more than 10%, with a large and still underutilized volume of wood waste and other renewable energy resources. At the same time, a significant part of the wood fuel used is firewood, primarily in rural areas. The work proposes an assessment of the energy potential of logging waste. It shows that with the existing volumes of wood harvesting, the wood waste share in energy production in the region may amount to 15-50%, depending on the degree of the waste use. The author also identified other renewable energy resources in the region and their possible role in its energy supply: hydro, wind, solar, peat, and tidal energy. The auhtor identified the districts of the region where creation and development of energy based on local renewable energy resources is most in demand. Mainly there are districts beyond the system of centralized power supply network, that cover some 19% of the region's area with more than 9% of its rural population, there electricity is supplied with dozens of small-scaled diesel power plants. For them there were assessed the volume of needed autonomous power capacities on the base of the local renewable resources.

Keywords: hydropower, electricity production, heat production, industrial waste, Arkhangelsk region, bioenergy, logging and timber processing, renewable energy sources, wind energy, rural areas

Abstract: The paper presents a combined analysis of the lithological, granulometric and mineralogical composition of unconsolidated sediments in the Sentsa River basin (Oka Plateau, Eastern Sayan, Russia). Complex analytical studies and drilling operations were aimed at studying the lake, river and moraine sediments that fill the river valley in order to reconstruct the conditions of their accumulation. Granulometric analysis, performed using sieve and laser diffraction methods, made it possible to establish the sequence of sediment accumulation in this dammed paleoreservoir and the position of the paleotable of the permafrost (at depths of 1.2 and 2.1 m). The mineralogical composition of alluvial sands confirmed the predominantly quiet water regime of their accumulation (in lake and lake-marsh conditions). The composition of moraine sediments and the structure of moraine ridges indicate the activity of water flows during the melting of the glacier, which formed a ‶layer cake″ of a terminal moraine ridge, as well as a stadial moraine with a thick sandy layer (more than 3.0 m) in the middle stream of the Sentsa River. Deep drilling allowed to establish for the first time the structure of the vertical section of the river valley and the permafrost thickness, which amounted to 44 m. A borehole with a depth of 45.1 m penetrated a section composed of frozen silts, clayey silts, clays and sands, as well as sub-permafrost groundwater. The cryotextures of unconsolidated sediments are predominantly massive and rare schlieren, with lenses and layers of ice up to 8-10 cm thick at different depths. Radiocarbon dating of a core sample taken from a depth of 1.5 m showed an age of 3510±120 years and confirmed the existence of an open water reservoir in the late Holocene in the Sentsa River valley.

Keywords: Oka Plateau, radiocarbon dating, moraine sediments, sedimentation rate, lithological composition, cryogenic texture, mineralogical composition, permafrost thickness, granulometric composition, unconsolidated sediments

Abstract: Aufeis is one of the most dangerous natural phenomena. The negative impact of aufeis is determined by the unexpected flooding of the territory and subsequent freezing of water, the formation of ice barriers, the icing of underground structures and communications (mines, tunnels, culverts, and sewer wells), as well as the icing of roads and railways, coastal hydraulic structures, etc. There are cases when explosions of aufeis mounds produce catastrophic disturbances within a few seconds. The aufeis that forms annually in the valley of the Buluus Creek is one of the most famous and studied aufeis of Central Yakutia. The aufeis was sampled from a vertical section. The aufeis is layered, and the thickness of the layers is 3-10 cm. In the upper part of the aufeis, the ice layers are thicker than in the lower. Sampling from the aufeis ice was carried out using a 5.1-cm-diameter steel crown driven by a Bosch electric drill. Measurements of the isotopic composition of oxygen and hydrogen in ice were performed using a Picarro L 2130-i laser isotope analyzer. The isotopic composition of the Buluus ice varies in a narrow range: δ18O values vary from −20.2 to −21.9‰, δ2H values vary from −159.5 to −173.7‰. Generally, the ice is isotopically slightly enriched compared to the surface water of the Ulakhan-Taryn creek, where the δ18O value is −22.18‰ and the δ2H value is −175.1%. Groundwater is isotopically close to the creek water; its isotope composition is also isotopically enriched compared to the ice of the aufeis, with δ18O values varying from −22.17 to −22.25‰ and δ2H values varying from −173.7 to −175.1‰.

Keywords: Central Yakutia, middle taiga, cryogenic soils, Lena River, Ulakhan-Taryn stream, Buluus, hydrogen isotope, oxygen isotope, permafrost, aufeis

Abstract: The object of the study was the unexplored soil cover of the Olsky section of the Magadan Nature Reserve. For this purpose, a route survey was conducted of 12 of the most characteristic tracts of the site available for hiking. The research methods generally accepted in Russian soil science were used. 11 soil subtypes were identified for the first time within the boundaries of the site, among which the most common are soils of the alphegumus and humus–accumulative departments, developing on granitoid derivatives overlain from above by an Aeolian cover of volcanic ash with a thickness of up to 0.25 m. A soil map has been compiled on which 9 contours of soil cover structures are outlined, among which the most widely represented combinations of ochreous podburs with sod-podburs illuvial-ferruginous ochreous, dry peat-ochreous podzols with ochreous podzols and dry peat-lithozems humus-peat, as well as ochreous gleevate podzols.  11 soil subtypes were identified for the first time within the boundaries of the site, among which the most common are soils of the alphegumus and humus–accumulative departments developing on granitoid derivatives overlain from above by an Aeolian cover of volcanic ash with a thickness of up to 0.25 m.A soil map has been compiled on which 9 contours of soil cover structures are outlined, among which the most widely represented combinations of ochreous podburs with sod-podburs illuvial-ferruginous ochreous, dry peat-ochreous podzols with ochreous podzols and dry peat-lithozems humus-peat, as well as ochreous gleevate podzols. The conclusion is made about the overwhelming influence of Kamchatka volcanism on soil formation and soil cover of the research area. The obtained results can be used for environmental purposes to replenish information about the environmental components of one of the poorly studied sites of specially protected natural territories of the North of the Far East, as well as in domestic soil science to clarify the genetic features of the influence of Kamchatka volcanism on the land cover of the vast oceanic region of the Pacific Ocean.

Keywords: ancient Kamchatka volcanism, the structure of the soil cover, natural areas, environment, soil map, region, Soil science, ochreous subtypes of soils, soil cover, soil

Abstract: The subject of research is the underground structures of the cryolithozone (permafrost zones). The design of such structures, in particular the choice of space-planning solutions, methods and means of fastening rocks, unlike structures located not in frozen rocks, has a number of features and is associated with the need to take into account the zone of thermal influence of chambers operated with different thermal conditions constantly or periodically. For example, when changing the type of thermal regime in the chambers in cases of natural or man-made accidents and catastrophes. The purpose of the research was to determine the zone of thermal influence of a single chamber of an underground cryolithozone structure, depending on the type of fastening used (in the presence and absence of a thermal protective layer) and the duration of the operational period, using various calculation formulas. To achieve this goal, three types of formulas were studied that determine the dependence of the dimensionless radius of thermal influence of chambers on Fourier and Bio criteria. Multivariate calculations were performed using the formulas, which are presented in the form of 3D graphs. The analysis of the performed calculations showed that the calculations for all three formulas give similar results in a fairly wide range of changes in the initial parameters. Moreover, the formula, which does not take into account the influence of the Bio number on the radius of thermal influence, gives a certain calculated margin. In general, it is shown that the higher the value of the Bio number, the less its effect on the depth of the thermal influence zone of the underground chamber. Small values of the Bio number (up to 5-6) are typical for cameras that are fixed with sprayed concrete or have special heat-protective coatings.It is established that when choosing space-planning solutions for underground structures to assess the influence of the thermal factor, it is quite acceptable to use an approximate formula to estimate the radius of the thermal influence of a single chamber. The scientific novelty lies in establishing the scope of the studied formulas for predicting the radius of the zone of thermal influence of cameras with various types of fastening and thermal protection.

Keywords: calculation formula, designing, the radius of thermal influence, thermal mode, cryolithozone, underground construction, type of support, thermal insulation, forecast, calculation

Abstract: The study of exogenous processes and their effects on natural and anthropogenic systems is a very important aspect for the development of Arctic territories. One of these processes is thermal erosion, which is widespread in the Yamalo-Nenets Autonomous District due to the presence of permafrost in the vast majority of its area. The main prerequisites for the manifestation of thermal erosion processes can be divided into several groups of factors. Firstly, the geomorphological characteristics of the territory play a key role: the lengths and slopes. Secondly, the lithological and granulometric composition of rocks, as well as ice content and temperature, determine the resistance of the soil to the thermal and mechanical effects of flowing water. Thirdly, the amount of precipitation is an important factor, especially precipitation in winter and heavy rainfall in summer. They contribute to a high concentration of runoff in short periods of time, which leads to rapid destruction of rocks and the removal of large volumes of loose material. Finally, the fixation of the top layer of soils by the root system can be considered the main reason that counteracts the development of thermal erosion. The purpose of this study is a prognostic assessment of the risks of the development of thermal erosion processes in the context of the observed climate warming. To assess the risks, data from climate modeling of the Yamalo-Nenets Autonomous District for the middle of the XXI century were used for an ensemble of climate models included in the CMIP6 project. The analysis of Google Earth satellite images and information about the geological and geomorphological features of the region are used for zoning the territory in terms of dynamics and dangers of thermal erosion. The result of the study was the compilation of a map of the Yamalo-Nenets Autonomous District by categories of risks associated with thermal erosion processes. It is shown that in the perspective of several decades, more than 50% of the region's area is subject to intensification of thermal erosion destruction of soils, which requires careful planning of economic development and design of protective structures. An attempt has been made to assess the impact of erosive and thermoerosive effects on the natural environment of the Yamalo-Nenets Autonomous Okrug due to climate change using the recommendations of this assessment by Order of the Ministry of Economic Development of the Russian Federation dated 05/13/2021 N 267. Climatic factors can seriously enhance the causes and negative consequences of the development of thermoerosion, while local manifestations should be assessed using field data based on the calculation methods.

Keywords: ice wedges, exogenous processes, permafrost, Yamalo-Nenets Autonomous Okrug, Yamal, Arctic, frozen grounds, climate changes, thermal erosion, Western Siberia

Abstract: The object of the study is the dispersed fractions of an aerosol substance in the snow cover. At the sampling sites located in the middle taiga zone within the Mezen-Vychegoda Plain on a high terrace in the Sysola river valley, 3 km west of the city of Syktyvkar, fresh snow and surface frost were sampled. The analysis of the ratios in the surface hoarfrost of subdispersed fractions of the aerosol substance was carried out in conjunction with the granulometric analysis of freshly fallen snow. Studies using the method of dynamic light scattering of the granulometric composition of an aerosol substance in freshly fallen snow and surface hoarfrost formed between snowfalls showed that a bimodal distribution of particles is recorded in all snow samples. At the same time, the distribution of submicron aerosol particles in frost samples is already characterized by the presence of three modes. Also, with an increase in the duration of the period between snowfalls in hoarfrost samples, a redistribution of particles between fine and medium fractions is observed in the direction of a significant increase in particles in the fine fraction, but the volume concentration of particles of the large fraction changes slightly. It is assumed that the identified circumstance is associated with the action of capillary forces and the adhesion of dry precipitation during the crystal formation of hoarfrost (it is proposed to call this phenomenon "frosty condensation"). A similar effect was also observed in the West Siberian southern taiga and the coastal tundra of the Lower Pechora region.

Keywords: rime, snow, solid hydrometeors, snowfall, snow pollution, aerosol fractionation, dynamic light scattering, granulometry, aerosols, adhesion

Abstract: The aim of the work is to obtain generalized simple formulas for calculating the coefficient of thermal conductivity of snow cover when calculating its thermal resistance. To achieve the goal, a comparison was made of the parabolic formula of N.I. Osokin, obtained on the basis of generalization and correlation analysis of existing dependencies for calculating the coefficient of thermal conductivity having fractional coefficients, with its simplified version with integer coefficients. Based on the linearization of the base Simple linear formulas for determining the coefficient of thermal conductivity depending on the density of snow for two characteristic density ranges (200-300) and (300-400) kg/m3 were also obtained. The percentage errors in the calculations of the coefficient of thermal conductivity of snow, which are possible with the simplification of the coefficients and linearization of the basic parabolic dependence of the coefficient of thermal conductivity on the density of the snow cover, are determined. It is established that the errors arising from the linearization of the basic function do not exceed 5%, which is quite acceptable in engineering calculations. The discrepancy between the results of calculations according to the basic and simplified formula (with coefficients rounded to integer values of the first order) does not exceed 1.5% in the entire considered range of changes in snow density. The results of numerical calculations are presented in the form of graphs that allow you to visually assess the impact of simplifying the calculation formula and its linearization on the accuracy of determining the coefficient of thermal conductivity of snow cover.

Keywords: approximation, simplification, calculation, accuracy, mistake, thermal resistance, snow reclamation, linearization of the function, snow, ground

Abstract: Ongoing active development of natural resources, changing climatic conditions (including permafrost melting) In Eastern Siberia, it is necessary to control changes in the ecological state of the environment, one of which is surface water. The Roshydromet system has established and successfully operates a network of regime observations of the state and pollution of surface waters of the Russian Federation, ensuring the unity of measurement of the content of major pollutants in water according to uniform methods certified in accordance with the requirements of regulatory documents of the Russian Federation and international standards. In this paper, the formation of the quality of the surface waters of the Lena River basin under conditions of non–stationary climatic processes on the one hand and the anthropogenic component on the other is considered. Based on the analysis of statistically processed long–term data (2011-2021) obtained by the state monitoring network of Roshydromet, an assessment of the water quality of the Lena River and its major tributaries - the Vitim, Olekma, Aldan, Vilyu rivers is given. The spatio-temporal distribution of characteristic pollutants in the water of the rivers of the basin has been studied: organic substances (according to BPK5 and COD), phenols, petroleum products, iron, copper and zinc compounds. It was found that in the conditions of the Arctic climate, the seasonal distribution of organic substances in surface waters was insignificant. The presence of heavy metal compounds in the water of the Lena River basin water bodies is mainly due to anthropogenic sources of pollution. In the long-term plan, the water of the rivers of the Lena River basin was assessed as the 3rd satisfactory quality class.

Keywords: water pollution, Republic of Sakha, tributaries of the Lena River, Lena River basin, pollutants, surface water quality, chemical composition of water, long-term trend, dynamics of concentrations, water quality assessment

Abstract: The historical analysis of the studies carried out during the 1950s-1980s by the staff of the Yakutsk Permafrost Research Station of the Obruchev Permafrost Institute of the USSR Academy of Sciences and since 1962 – organized on its basis by the Permafrost Institute of the Siberian Branch of the USSR Academy of Sciences and aimed at studying the coastal-shelf zone of the Laptev Sea and the East Siberian Sea. The sources for the preparation of the article were the archival materials identified by the author from the funds of the Russian State Archive of Economics and the Archive of the Melnikov Permafrost Institute of SB RAS, as well as scientific literature data. The work carried out made it possible to show the significant activity of researchers in the study of subbottom permafrost. Its drivers were both purely cognitive interest and the needs of the industrial development of high latitudes. In the course of the surveys carried out, data were obtained characterizing the prevalence and thickness of subpermafrost, its temperature regime, composition and other properties.

Keywords: subbottom permafrost, geocryology, the USSR Academy of Sciences, scientific research, history of science, shelf of the Arctic seas, East Siberian Sea, Laptev Sea, Yakutia, Arctic

Abstract: The subject of the study of the proposed article is the gas component of the cryolithozone. If the solid and liquid phases of frozen rocks have been studied sufficiently deeply and systematically, then the gas component has been studied weakly and fragmentally. The object of the study is gas-saturated frozen soils, their spatial distribution and properties. Studies of recent decades have shown that the gas component plays a significant role in the structure and properties of frozen rocks. The author examines in detail such aspects of the topic as the effect of gas on the physical and mechanical properties of both thawed and frozen soils. Special attention is paid to the overlap of capillaries in the soil with gas, an increase in pore pressure, a weakening of soil consolidation and connections between soil particles. This, in turn, is expressed in a decrease in strength and density while increasing compressibility and porosity.      The novelty of the study lies in the fact that for the first time a comparative analysis of data on the content of the gas component of the pressure in it and the processes occurring in frozen rocks was carried out. A special contribution of the author to the study of the topic is that the influence of free gas on their physical and mechanical properties is shown. The relevance of the topic under consideration is due to the need to study the patterns of deformation of frozen rocks depending on the degree of gas saturation. The article analyzes the state of the regulatory framework that takes into account the influence of gases on strength and deformative properties. Their almost complete absence was recorded. The importance of taking into account the possible increased pressure in gas-saturated frozen rocks in the development of research methods and regulatory documents for their use in engineering-geological and design work is shown. The materials considered indicate that gas-saturated frozen soils are a significant and important part of the cryolithozone and their study should be carried out within the framework of an independent section of geocryology.

Keywords: gas hydrate decomposition, gas saturated soils, pneumatic rupture, gas hydrates, pressure filtration of gas, breaking strain, plastic deformation, gas filtration, permafrost, fracturing

Abstract: This paper presents the results of field studies conducted at the MSU meteorological site for the winter period of 2022/2023. The purpose of the observations was to study the development of the snow column and its spatial variability in one winter season. Field research consisted of analyzing stratigraphic layers of snow and measuring their density. The data obtained made it possible to characterize and evaluate changes in snow layers, structure, and density in spatiotemporal terms. The results of the work are displayed on the graphs of the spatial and temporal variability of the snow cover for 2022/2023. The evolution of the snow column over the winter period is analyzed. The analysis of observations reflects a high spatial and temporal variability of snow cover in winter, which allows not only to evaluate and compare the data obtained with past studies but also to supplement and improve the already available information on the heterogeneity of snow cover.

Keywords: heterogeneity of snow cover, research, winter period, snow layer, winter season, weather site, MSU, snow thickness, spatio-temporal heterogeneities, snow cover

Abstract: When designing cryolithozone engineering structures, proper consideration of the thermal factor largely determines their subsequent reliable and safe operation. One of the important indicators when choosing design solutions is the coefficient of thermal conductivity of materials used in the construction of objects. The accuracy of determining the thermal conductivity coefficient also depends on the accuracy of determining the thermal resistance of heat-protective structures. The coefficient of thermal conductivity of materials is usually selected from the reference tables. When using mixtures of materials, the coefficient of thermal conductivity is determined by calculation. The purpose of this work was to compare the calculated values of the thermal conductivity coefficient of binary mixtures (a mixture of binder and filler) determined by the formulas of K. Lichtenecker and P. Schwerdtfeger. The comparison was carried out in the range of changes in the properties of materials characteristic of heat-accumulating and heat-insulating mixtures. It is established that for heat-accumulating mixtures, both calculation formulas give similar results. For thermal insulation mixtures, the results differ significantly. Moreover, the discrepancy for some ranges of changes in filler concentrations is hundreds and thousands of percent, which indicates a complete disagreement of the results obtained. The validity of applying one or another formula in different ranges of changes in the initial parameters for thermal insulation binary mixtures needs separate special studies. Note that the results obtained and the conclusions drawn can be extended to compare the formulas of K.Lichteneker and V.I.Odelevsky. At the same time, at this stage of research, it is not possible to reliably determine which of the two formulas should be used when calculating the thermal conductivity coefficient of thermal insulation mixtures.

Keywords: forecast, comparison, construction, ratio, binary mixture, thermal conductivity, cryolithozone, automobile road, formula, calculation

Abstract: The results of the application of geo-radar profiling for the study of soils and underlying rocks of polygonal bogs of the Pur-Taz interfluve (North of Western Siberia), functioning in natural and anthropogenic disturbed conditions, are presented. The research area belongs to the southern tundra with a predominantly continuous distribution of permafrost rocks. The construction of highways in the North of Russia is one of the main factors of anthropogenic impact on the tundra geosystems of the cryolithozone, affecting the temperature regimes of soils and the depth of permafrost. The features of spatial differentiation of the depth of occurrence of permafrost rocks on the site of polygonal swamps intersected by a federal highway were determined by the methods of geo-radar profiling. Georadiolactic profiling made it possible to determine the configuration of the depth of the permafrost roof both in natural and anthropogenic disturbed areas of polygonal swamps. The maximum lowering of the permafrost roof is determined at the base of the road embankment and does not exceed a depth of three meters. Despite the deep occurrence of the MMP roof under the road embankment, the thickness of the thawed buried peat horizons here is similar to that of the seasonally shallow layer of undisturbed peat polygons. The features of spatial differentiation of the depth of the permafrost roof in the polygonal swamps intersected by the bulk highway in the North of Western Siberia are similar to those characteristic of regions with a continuous low-temperature cryolithozone. The method of manual probing of the permafrost roof was used to verify the results of geo-radar profiling within undisturbed areas.

Keywords: Western Siberia, southern tundra, anthropogenic disturbances, highway, manual sensing, tundra soils, seasonally small layer, permafrost rocks, georadar, polygonal swamps

Abstract: One of the important parameters determining technical solutions in the design of highways in the cryolithozone is the depth of thawing of the soils of the road base. The aim of the work was to quantify the degree of influence of the iciness of the soil foundations of roads in the cryolithozone on the depth of their seasonal thawing. For the analysis, the classical formula for calculating the thawing depth for bodies of plane symmetry, obtained by solving the single-phase Stefan problem, was used. The results of calculations are presented in the form of 2D and 3D graphs, which allow us to visually assess the effect of the iciness of the soil and the degree of its change during the operation of the road on the depth of thawing of the road base. It was found, in particular, that the degree of change in the depth of thawing at the same value of the increase in ice content in different ranges (for example, from 10 to 20% and from 30 to 40%) for the considered typical case of the ground base of the cryolithozone decreases by almost 1.3 times. It is shown that the greater the initial iciness of the soil, the degree of decrease in the depth of thawing when the iciness changes by a constant value will be less. A 3D graph was built to determine the depth of thawing of the soils of the active layer of the road base in a wide range of possible changes in ice content during the construction and use of the highway. The availability of a schedule allows to quickly assess possible options for changing the depth of thawing and make a correct, informed technical decision when designing the road. For example, when assessing the need to use a special heat-protective layer in road clothing. Further directions of research in this area should be aimed at studying the effect of humidity (iciness) of dispersed soils on the depth of thawing of road foundations, taking into account the dependence of the density and thermal conductivity of the soil on the iciness.

Keywords: degree of change, designing, 3D graph, iciness, thawing depth, forecast, permafrost, automobile road, temperature, calculation

Abstract: This article examines the reliability of ice data presented in the HadISST1 database (Hadley Centre Sea Ice and Sea Surface Temperature data set) of Hadley Meteorological Center (Hadley Centre for Climate Prediction and Research, Met Office, UK). The criterion for the reliability of HadISST1 database on the Northern hemisphere serves the average multiyear annual course of insolation in the Northern Hemisphere and the average multiyear annual course of insolation in 5-degree latitudinal zones at the upper boundary of the atmosphere, phase-shifted by two and three months to the past. It is revealed that the representative criterion for assessing the reliability of the business database is the average multiyear course of insolation in 5-degree latitudinal zones shifted by two months to the past. Evaluation of the data array on the Northern Hemisphere on the basis of the selected criterion demonstrates the overall high reliability of ice data reflected therein. However, there are two areas that differ in the degree of reliability of the presented data: 1) pack, drift ice with high negative values of the correlation coefficient; 2) coastal zone, in which the correlation is virtually absent (shore ice and flaw leads). The weak (or absent) correlation is observed over a significant length of the coastal zone in the Arctic Ocean, as well as in the straits and bays of the Canadian Arctic Archipelago. It is established hat the correlation coefficient of the annual course of the ice flow in the cells of the array of size 1 with the annual course of insolation of the Northern Hemisphere and the corresponding 5-degree latitudinal zones increases from the past to the present. This indicates the need for the correction of ice data in the early time range of the array (1901–1978), which precedes the time of the beginning of satellite observations.

Keywords: Arctic Ocean, The Arctic, Arctic seas, insolation contrast, insolation of the Earth, changing the area, sea ice, insolation, atmosphere, Earth

Abstract: The subject of this article is the pollen spectra of the samples from the surface of Romantic's Glacier, located in the Polar Urals in the Rai-Iz mountain range, as well as generalization of the results of published studies dedicated to glaciers of the Urals. The author also examines the pollen spectra of massive ice, which can be attributed to ice of atmospheric origin on the basis of similarity with the pollen spectra obtained from the surface of the glacier. The article reviews climatic peculiarities of the Polar Urals due to the existence of glaciers below the snow line, namely the landscapes of the Polar Urals, including vegetation as a source of pollen and spores falling onto the surface of glaciers of the Polar Urals, as well as possibility of distant pollen drift to the surface of Romantic’s Glacier. The main result consists in the conclusion that the composition pollen spectra of the Romantic’s Glacier in the Rai-Iz mountainous area is mainly determined by the long-range transport of pollen and spores from the western and south-western regions in a latitude direction. The pollen spectra obtained from the surface of the Romantic’s Glacier are characterized by significant presence of various pollen from broad-leaved rocks of lip, maple, oak, and hazel. Pine pollen and high forest birch are prevalent. Local vegetation is very poor. However, the pollen spectra indicates pollen of heath and crowfoot family, and grasses.

Keywords: long distance transported pollen, pollen spectra, Polar Ural, glacier lake, glacier ice, glacier, spores, pollen, vegetation of mountain tundra, firn

Abstract: This article covers the history of scientific research of the Nizhnekolymsk tundra, conducted over the period from 1970 to 1987 by the employees of the Institute of Biology of the Yakut Branch of the Academy of Sciences of USSR (Yakutsk). The subject of this research is the biochemical composition of plants from the family of sedge and grass – Егiорhorum роlуstасhiоn and Arctophila fulva) as the most common communities. It was conducted in tundra pastures in the lower reaches of the Kolyma River for rational economic management. One of the largest state owned farms of Yakutia “Nizhnekolymsky” specializes in reindeer herding – the traditional activity of indigenous peoples, was located in this area. In the past, this area was referred to as Hallerchinskaya tundra; it covered low left bank of the Kolyma River from delta to the forest boundary on the south and Konakovsky uplands in the west. Within the limits of Hallerchinskaya lowland in the rural locality of Pohodsk was located the “Nizhnekolymsky” geobotanical station. The method of models developed by staff members of the Institute of Biology was applied in monitoring the formation of aftergrass and determination of productivity reserve, as well as in selection of quadrats in the subarctic tundra. The main conclusions consists in the statement that the use of the such method for determining the phytomass reserve allowed conducting a prolonged observation over aftergrass formation in the same quadrats, and thereby discerning the natural development process towards reduction or increase of the studied species.

Keywords: phytomass, deer pastures, pingo, polygonal-roller formations, Lower-Kolyma subarctic tundra, Kolyma river, Kolyma lowland, Arctic, Eriophorum polystachion L, Arctophila fulva

Abstract: This paper demonstrates the results of diatom analysis of the Holocene sediments from the southeastern part of the Tersky Coast of the White Sea. The main subject of the study is the diatom assemblages’ concentration and composition, as well as the ratio of the main diatom ecological groups in sediments. The study sites were located on the Tersky Coast from the village Chavanga to the right coast of the Varzuga River, at heights from 17 to 52 m. Our reconstruction of the Tersky Coast of the White Sea development is based on diatom study of Holocene sediments from three cores. Age was determined according to radiocarbon dating. In this work, the author determines the features of environmental development, starting from the first half of the early Holocene, clarified the age of the main transgressive stages - Folas, Tapes, Trivia and the absolute heights of their marine sediments. According to the changes in concentration and composition  of the main ecological groups of diatoms, the author records the significant trends in the water temperature changes in coastal reservoirs and hydrobiological conditions in the Holocene, such as short-term decrease in the temperatures of the end of Boreal and the first half of Atlantic time, the Holocene hydrobiological optimum, and changes in temperatures of the Subboreal and Subatlantic time.

Keywords: paleogeographic reconstructions, the Holocene, peatbog, radiocarbon dating, diatom analysis, Tersky Coast, the White Sea, sea level changes, Atlantic Waters’ advection, the Arctic

Abstract: The object of this study is the Far East, located in a steadily active transition-contact zone of the two greatest structures of the Earth – the Asian continent and the oceans, and Arctic and Pacific oceans. The subject of this study is the nature of the relationship and interaction of relief formation and substrates (litho-, chion - and phyto -) generated by the three spheres of the physical and geographical shell of the Earth and composing the upper horizons of its solid shell. The goal of this work is to elucidate the multifaceted relationships and interactions between substrates and geomorphological processes in the south and north of the Far East. The data (1955-2011) of the author's research, as well as available literary and stock sources are used. Comparative geographical and information methods were used in the analysis. The novelty of the study lies in the fact that the substrates involved in relief formation in different climatic conditions of the Far East, differ in unique appearance and organization.  Results obtained from original materials, with the relevant data from the literature, can be useful in choosing the strategy for environmental management in all of the areas where it must be utmost "gentle", taking into account existing risks and their identified environmental constraints.

Keywords: phytogenic, chionogenic, lithogenic, substrates, relief formation, south, north, Far East, rational nature management, results

Abstract: The subject of this study is the Wrangel Island - the island of polar bears (local name - "Umkilir"). There is no indigenous population as such; the area is 7,600 km², out of which 4,700 km² is occupied by mountains in its central part; the highest point is 1,096 m (the Soviet Mountain). The object of this research is the polar landscapes that develop in xerocryotic environment and are notable for the unique appearance and arrangement. The goal and objectives consist in cognizing the nature of the regional climatic morphogenesis and characteristics of the organization (structure and functionality) of geosystems that possess augmented stability in typical environments of landscape genesis and are extremely sensitive to the effects of anomalous factors and processes. The materials and methods contain the data from the author’s permafrost-geomorphological research in Chukotka (1957-1959; 1971-1972), as well as accessible literary sources. The conclusion is made that the current development of Wrangel island’s terrain is defined and controlled primarily by the specific polar climate (directed continentalization of natural conditions; small amount of solid precipitation; high "wind tension" in winter, when snow is intensively blown into the sea; etc.). This results in the absence of the active loci of glaciation. It is determines that the development of morphogenesis on the island proceeds along the path of persistent displacement of nivation processes by constantly expanding and already prevalent cryogenic processes. Such trend of landscape development will continue for the near future.

Keywords: types of climomorphogenesis, development, cryogenic forms, climate, surface arrangement, polar landscapes, discovery, Wrangel Island, continentalization, nature reserve

Abstract: The object of this work is the polar landscapes of Eastern Chukotka. The research task is to determine the nature and specificity of geological and geomorphological structure of the territory in typical and anomalous environments of cryolithomorphogenesis. The goal consists in the theoretical and practical studies of sustainability and plasticity of the polar geosystems on the background of climatic changes, amid the conflicting interactions between continentality and oceanicity. Special attention is given to the detailed analysis of morpholythogenic effects of the typical and anomalous (extreme – critical and crisis, as well as disastrous) processes and factors. The main conclusion lies in the following: in the course of development of the northern territories and increased interference in their natural environment, all permafrost processes are activated, with the leading role of thermokarst. Special contribution into the study is defined by the fact that, in the context of the upcoming continentalization of climate and assumed conservation the territory in Eastern Chukotka, the traceable natural risks are reducing, and the geosystems, most commonly, retain their initial sustainability. The exogenous crisis situations and disasters are forecasted, which allows making adjustments to the practice of optimal natural resource management. The scientific novelty lies in tracing the sustainable development of the territory, considering not only the compound, but also thorough complexation of the living and fossil.

Keywords: anthropogenic, natural risks, sustainability, zoning, structure, belt, polar landscapes, geosystem,, Arctic, Eastern Chukotka

Abstract: The subject of this research is the diverse forms of space and time reflection in the development of geosystems (GS). The object of this research is the GS related to space and existing only in time. The author carefully examines such aspects of the topic as space and time, inseparable from each other, and if compared to other characteristics, are the paramount attributes of geosystems (natural, technogenic, and social) in the typical and anomalous environments. Particular attention is given to consideration of "time", characterized by the active (physical) properties influencing the events in geographic space and manifesting in opposition to the normal flow of processes, leading to the destruction of GS. The main conclusions lie in the positions determining the exogenous crisis situations and disasters as predicted. Author’s special contribution is the revealed opportunity to make certain adjustments to the practice of natural resource management considering sustainable development of the territory. The scientific novelty consists in tracing the sustainable development of the territory, which is based on taking into account not only typical, but also anomalous natural processes and phenomena. Because the exogenous crisis situations and disaster are predicted, the practice of natural resource management can be adjusted considering sustainable development of the territory.

Keywords: Far East, natural risks, geographical cover, geosystems, development, time, space, Sustainable development of the territory, disasters, exogenous crisis situations

Abstract: The subject of this study is the peatlands of the Seymchan-Buyunda depression, in particular the composition of gases contained in the permafrost peatlands and ice-wedge ice. Special attention is paid to conditions of the peat formation, features of the Seymchan-Buyunda depression climate and the Magadan region in general, the characteristics of the main types of vegetation, soil cover and landscape. The trend of changes in the average annual air temperature in the area of Seymchan town is considered. To estimate the time of formation of ice-wedge ice, the composition of spring pollen rain during the accumulation of the ice wedges was reconstructed. The composition of trapped gases in peatlands is established. Determination of gas composition was carried out using the chromato-mass-spectrometer Hitachi M-80. There are high methane content in frozen peat bog Chokachi and lake water on the surface of the peat bog; it was discovered that the lake on the surface of the peatland is both, a trap for gases released from the thawing peat and a depositing medium, in which the processes of reduction of hydrocarbons take place intensively; in the composition of gases trapped in the frozen peatland there is a high content of hydrogen, which is one of the mandatory conditions for the life of methane-forming bacteria.

Keywords: pollen, Seymchan-Buyunda depression, ice-wedge, Upper Kolyma, trapped gases, polygonal peat, methan, hydrogen, gas chromotography, hydrogen sulphide

Abstract: The subject of this research is the gas emission crater (Yamal crater), located in the southern part of Bovanenkovo deposit on the Yamal Peninsula. Generalization of data on the structure of crater soils components, natural conditions and laboratory results, allowed building a phenomenological model of the Yamal crater, with identification of different stages of its development. The cause for the emergence of the gas emission craters is the formation within the subsurface of permafrost rocks of the underground gas accumulation zones with the abnormally high pressure. The diverse geological and thermodynamic factors substantiate the various scenarios of their development. The main research method lies in consideration of the different structural elements of the Yamal crater as the phenomena that reflect the processes of its formation. In determination of the processes that form the gas emission craters, the authors apply the method of analogies. The conclusion is made that the gas emission craters eventuate the self-development of the fluid dynamics geosystems, which are the local ice-surface gas-saturated formations in non-equilibrium thermodynamic state in relation to the enclosing permafrost rocks. The development of the selected geosystems is defined by paragenetic links between gas filtration processes and deformations of gas-saturated ice-surface material (from viscoplastic motion to brittle fracture). The Yamal crater is a particular example of a full and complete life cycle of the development of selected geosystems: from the initial stage – the formation of conditions for decomposition of gas hydrates, to the final stage – the explosion and release of ice-surface material.

Keywords: ice ground saturated geosystems, fluid geodynamics, fluids, gas filtration, dissociation of gas hydrates, ice flow, plastic deformations, permafrost, stage of development,, paragenetic relationships

Abstract: This article examines the argumentation of the main hypothesis of disappearance of the large Pleistocene fauna. The four components of the problem are being determined and discussed – chronological, landscape-climatic, anthropogenic, and evolutionary. The author analyses the possible effect of the dating method upon the perceptions regarding the chronology of rise and fall of the populations of mammoth fauna, as well as different landscape factors of the destruction and disposal of the fossil fauna, temporal connection of the mass destruction of animals with the eras of climatic cooling and warming. The role of anthropogenic factor of mammoths’ extinction is being evaluated. Special attention is given to the loesses as a factor that forms the habitat of Pleistocene fauna. The article suggest several original hypothesis of mammoths’ extinction that are based on the principles of biospheric evolution and catastrophism. Degradation of mammoth fauna at the turn of Pleistocene and Holocene was significantly affected by the following: rapid increase of zonality of the natural environment with reduction in the area of intrazonal landscapes; disruption of the patterns of seasonal and long-term migration of Pleistocene animals, primarily most vulnerable to changes in ration of the large mammals; amalgamation of the resource-viable zoocenosis that led to degradation of grazing lands and disruption of trophic chain. The key role in disruption of the migration patterns and pasture exhausting is assigned to the thermokarst catastrophe.

Keywords: paleogeography, thermokarst, ground ice, loess, extinction mammoths, glacial cycle, paleozoology, Pleistocene faune, tundra-steppe, yedoma

Abstract: The research subject is the varieties of subrecent pollen spectra in the unbroken surface layer of bottom sediments of the Laptev Sea shelf, which had been lifted by multicorers in the expeditions ARK 27-3 and Transdrift XXI in 2012-2013 on the shelf and continental slope. The authors substantiate the possibility of reconstruction. The authors consider how the following aspects are reflected in marine pollen spectra: 1) the level of ice coverage of the sea basin, which can be seen in the presence and concentration of index types of marine cysts of dinoflagellates; 2) oscillations of the river flow, assessed by the changes of concentration of organic suspensions of terrigenous genesis in bottom sediments (spores, pollen, fresh-water green algae), transferred mainly from the yedoma sediments; 3) transformed Atlantic water migration, which can traced by index types of microfossils; 4) climate conditions, defining the level of productivity of the flora of the dominating biomes of the shore, pollen to the Laptev Sea shelf comes from. The main research method is the study of marine pollen, which includes the analysis of the species composition and the changes of concentration of terrigenous and water palynomorphs in bottom sediments collected in the southeastern part of the Laptev Sea in the paleovalley of the Lena river, which was drowned during the Postglacial transgression. The obtained varieties of quantitative and qualitative composition of pollen and non-pollen palynomorphs in the unbroken surface layer of bottom sediments and their comparison with the results of the study of pollen from yedoma complex of northeastern Siberia help evaluate the modern conditions of formation of marine pollen spectra. 

Keywords: bottom sediments, cysts of dinoflagellates, green algae, spores, pollen, subrecent pollen spectra, yedoma, Laptev Sea, inner shelf, outer shelf

Abstract: Holocene ice wedge structures in the arctic tundra in the Tambey river valley and in the Belyi Island are the subject of the study. The author studies the pollen spectra in the ice wedges and surrounding sediments and their chemical composition. To substantiate paleograhic reconstructions, the author analyzes radiocarbon datings of the Holocene sediments from the studied areas and the surrounding territories. Pollen analysis is the main research method. Adjacent sediment samples have been studied according to the standard procedure, but without acetolysis mixture. Pollen has been extracted using the simplified method due to low pollen concentration. The main result of the study is the systemization of the data of palynological analysis of Holocene ice wedges located in the zone of sea-level changes' imact. The author shows that ice wedges in the Tambey River valley had been accumulated from precipitations and because of the inundation by marine water. Ice wedges in the first marine terrace of the Belyi Island are characterized by the abnormally high concentration of marine salt, but the salinization is caused by ice wedge formation on the sides of remnant shallow saline lakes, not by sea-level changes.

Keywords: climatic fluctuations, peat, Holocene, pollen spectra, ice wedge, radiocarbon age, Yamal Peninsula, local pollen zone, sporo-pollen charts, North-West Siberia

Abstract: The subject of the study is the content of trace elements (heavy metals and metalloids) in the Late Pleistocene ice-wedge casts of three yedoma blocks of Northern Yakutia: Kular, Bison and Duvanny Yar. Yedoma deposits of Duvanny Yar are exposed on the right bank in the lower course of the Kolyma River, near the Duvanny riffle, in the Kolyma Lowland. It is drained by the northward flowing Kolyma River, the sixth largest river flowing into the Arctic Ocean. The lowland is bordered by the North Anyuy Range to the east, the Yukagir Plateau to the south, the Alazeya Plateau to the southwest and the Ulakhan-Sis Ridge to the northwest. The Late Pleistocene Bison yedoma complex is located on the right bank of the Kolyma River, in the mouth of the Lakeevskaya Channel 15 km below the Duvanny riffle. Yedoma near the Kular village in the foothills of the Kular range is located on the mild slope of southern aspect in the valley of the Burguaat creek in the form of an inclined slope extending over a slope of more than 1 km. The main reseacrh method is atomic absorption spectroscopy, performed in the V.V. Dokuchaev Soil Science Institute. Samples of ice wedges were sampled in the field in polyethylene bags, melted at a temperature not higher than 15 °C and poured into chemically inert plastic bottles. The main conclusions of the study are as follows: a) in the late Pleistocene ice-wedge casts of the Bison and Duvanny Yar sections, lithophile elements (Mn, Sr) are significantly distinguished in comparison with the Kular section; b) the content of Sr in the ice of the Bison section is below the world’s average for surface water; c) Mn and Fe, highly mobile in gley reducting medium, are represented in the ice of the Duvanny Yar and Bison sections in much larger quantities than in the Kular section; it can be connected with different redox conditions during the formation of ice wedges. Probably in Kular the conditions were oxidative (for a long time) or more alkaline than in other sections, and in Duvanny Yar and Bison – mostly gley reducing and acid.

Keywords: ice-wedge cast, Duvanny Yar, Bison, Kular, Northern Yakutia, yedoma, metalloids, heavy metals, Late Pleistocene, clarke (mean concentration)

Abstract: The authors of the present work consider heavy metals content in the snow cover and glacial ice of the Polar Urals and the vicinity of the Mt. Elbrus region (Central Caucasus). In order to define the background hydrochemical constitution of the snow cover of the Polar Ural region in 1999, the authors study three snowfields, near the Polar Ural village, 2.5 km and 5 km from it; in the winter of 2003 near the Polarny settlement the authors explored the structure of the snow layer in the trial pit. In 2000, a small glacier (Glacier No.1) located in the on the slope of the southern aspect, was studied on the slope of the Small Paipudynsky ridge. In the Central Caucasus, studies were carried out on the glacier of Garabashi in the southern slope of Elbrus, the snow layers were studied during the summer and winter seasons: in the summer of 1998, in January 2001 and in June 2001. Glacier ice of the Greater Azau glacier was also studied. Analytic measurements of the trace elements content (Fe, Zn, Cu, Mn) were performed by atomic absorption spectroscopy at the V.V.Dokuchaev Soil Science Institute. The concentrations of trace elements in snow and glacial ice of the Polar Urals are small, averaging 0.005 to 0.02 mg / l, among the measured Fe, Zn, Cu, Mn, the highest concentrations are typical for Mn (up to 0.05 mg / l). An insignificant increase in the concentrations of heavy metals in the winter snow-summer snow-glacial ice series was noted. Dependences of the concentration of heavy metals on the morphological species of ice were not detected. For the snow cover and the glacial ice of Garabashi glacier and the adjacent slope there is also a certain tendency of increasing concentrations in the winter snow series to summer surface snow and to infiltration ice. The main minor elements in the snow and ice of the Garabashi glacier in the Caucasus are zinc and iron, the concentrations of which range from less than 0.02 to 0.6 mg / l (iron in infiltration ice) and from 0.01 to 0.22 in ice. The maximum content of heavy metals is confined to the horizons of infiltration ice. In seasonal winter and summer snow, the concentrations of almost all measured trace elements range from less than 0.01 to 0.03 mg / l. In the ice of the Big Azau glacier in the Elbrus region, the concentrations of trace elements are extremely low (less than 0.005 mg / l).

Keywords: pollution, Anthropogenic, Seasonality, Caucasus, The Polar Urals, glaciers, ice, snow, heavy metals, reference areas

Abstract: The authors study the Holocene syngenetic ice wedge casts of five regions of the Yamal Peninsula: within the thick peat bogs in the Shchuchya River valley and near the Seyakha settlement, in the floodplain of the Erkutayakha and Lakkatoso Rivers and within floodplain sediments of the Ob Bay in vicinity of the Mys Kamenny settlement in eastern coast of Yamal Peninsula. The width of the top of ice wedges in peatlands varies from 0.5 to 1.6 m, their height is from 2 to 5 m, the width of the ice wedges in the floodplain and marsh and swamp also varies from 0.5 to 1.8 m, the visible height is not more than 2 meters. Samples of ice were taken from ice wedges vertically and horizontally. To study the genesis of the water that participated in the formation of Holocene ice wedge casts and ice lenses from the enclosing sediments, the author analyze the content of trace elements and heavy metals. The analysis of trace elements and heavy metals is based on atomic absorption spectrophotometer (AAS-3) at the V.V. Dokuchaev Soil Science Institute. The mineralization and chemical composition of water-soluble salts in segregated and ice wedges are determined in the same place. The radiocarbon dating of the surrounding sediments aging of the ice wedges is carried out at the Geological Institute of the Russian Academy of Sciences. Holocene ice wedges are ultra-fresh and fresh, their mineralization varies from 20 to 200 mg / l, hydrocarbonates and calcium dominate in the ion composition. Participation of chlorides in the ice wedges on terraces indicates the influence of marine aerosols, the same for the ice wedges on the floodplain means the direct participation water of Ob Bay in their formation. The increasing of iron ions in some fragments of ice wedges, comparable to their content in segregated ice in the peat bog, may indicate a periodic participation of swamp waters in the formation of ice wedges.

Keywords: peatlands, floodplain deposits, heavy metals, trace elements, ion composition, salinity level, Holocene, ice wedge casts, laida, segregated ice

Abstract: The authors study the formation of isotope-oxygen composition of a snow mantle of Bratsk and the fresh snow in Baikal region and define the main trajectories of air masses, bringing precipitation to the city of Bratsk during the cold seasons. The research area covers the city of Bratsk and the points in Irkutsk region – the village Khidiakovo (18 km from Irkutsk), the village Kultuk on the southern coast of the lake Baikal, the mountain Snezhnaya of the route Irkutsk–Bolshoye Goloustnoye and the Tunkin valley in the Republic of Buryatia. The authors register the exceeded content of sodium (4-66 times) in the city snow mantle samples compared with the background snow mantle. Though the man-caused origin of sodium in snow is obvious, the natural causes are also possible. It can be brought by air masses, for example, from the Arctic coast. The study is aimed at this hypothesis testing. The research methods include the isotope method (assessment of the content of stable oxygen-18 in snow, both fresh and settled) and the reverse trajectory method, based on the Semi-Lagrangian scheme HYSPLIT for the period from December 2015 till March 2016 with the end points at the altitude of 3000m at 12 UTC. The average ratio of oxygen-18 content (expressed in the δ-ratio as the content of heavy oxygen in relation to the standard) in the snow mantle in Bratsk was -26, 54‰ in March 2015. Inside the snowpack the δ-rates vary from the horizon to the horizon from -21,52 to 28,1‰. It is considered as a relatively “heavy” isotope-oxygen composition. The authors find out that the influence of the Arctic air masses on the isotope composition of the snow mantle in Bratsk is quite insignificant. Of 44 precipitation days for the period from December 2015 till March 2016, 21 case was connected with the western air-mass transport from the Arctic, 5 cases were connected with the moisture coming from the Arctic sector, 15 cases – with the continental source and 3 cases – with the Sea of Okhotsk. 

Keywords: masses, air, Arctic, precipitation, isotope-oxygen composition, Bratsk, trajectories, snow mantle, snow, the Baikal region