Ice and Snow (E-Journal) / Лёд и Снег
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Новый Каталог ледников России по спутниковым данным (2016–2019 гг.)
Get PDFThe new Inventory of the Russian glaciers has been created at the Institute of Geography of the Russian Academy of Sciences mainly on the basis of the Sentinel 2 satellite images for 2016–2019 with the aim of assessing the current state of glacier systems and as a basis for monitoring and re-inventorying. Delineation of glacier outlines was manually made to reduce uncertainties, especially for small glaciers. The database structure is compatible with the global and national glacier archives and includes the main glacial parameters. Additionally a classification of possible catastrophic phenomena of glacial genesis was developed: dynamically unstable glaciers, glacier lakes, icebergs, etc. The data base is available online (www.glacrus.ru). At present, there are 22 glacial systems in Russia with a total area of 54,518 km2. The largest glacial systems by area are located in the Arctic archipelagos: Novaya Zemlya, Severnaya Zemlya, and Franz Josef Land. The glacial systems of the Caucasus, Kamchatka, and Altai are the largest by area in the continental part of Russia. The main group consists of 13 small glacial systems, the area of which does not exceed 100 km2. They are located in different glaciological zones: from the De Long Islands in the Arctic to the Eastern Sayan in southern Siberia. Since the compilation of the USSR glacier Inventory (1965–1982), the area of glaciers has decreased by 5,594 km2, or 9.3%. The area of polar glaciers has decreased in smaller degree than that of glaciers in mountainous regions. The results of our research confirm the trend of reducing the area of glaciers throughout the Russian territory. The magnitude and rate of changes depend on local climatic and orographic features. The exception is the glaciers of the volcanic regions of Kamchatka, the area of which has increased or remained unchanged.Создан Каталог ледников России на основе спутниковых снимков Sentinel‑2 (2016–2019 гг.) (www.glacrus.ru). Он содержит информацию о 22-х ледниковых системах общей площадью 54 518 км2. По сравнению с Каталогом ледников СССР (1965–1982 гг.) площадь ледников на территории России уменьшилась на 5594 км2, или на 9,3%. Величина и скорость изменений в разных районах сильно отличаются и зависят от местных климатических и орографических особенностей
Моделирование перераспределения снежного покрова – ключевого параметра зимних биотопов копытных Дальнего Востока
Get PDFThe properties of snow cover, one of the most important abiotic factors for survivability of animals (mainly hooves) in winter, are considered. To analyze possible consequences of this influence, it was necessary to develop a special parameterization of snow cover properties differing from those used in solving hydrometeorological problems. In this paper we present the biotopic approach to spatial and temporal modeling of the snow depth and structure at the mesoscale level. For this scale level, the main factor determining the snow cover depth and structure is the distribution of plant associations (the vegetation cover) on mountain slopes of different exposure and steepness. Our cartographic model of the vegetation cover was developed based on the results of decoding the hierarchical multispectral satellite images. Each combination of a vegetation type, exposure, and steepness of a slope has its own snow accumulation coefficient, which allows calculation of the snow depth in a particular biotope. We propose to analyze winter animal habitats using two parameters depending on the depth and structure of the snow cover: a passability and the food availability. Similarly to the map of plant associations exerting effect on snow cover, a map of plant communities of forage biotopes of specific animals has been built, and a certain snow depth was assigned to each type. The forage biotopes were ranked according to degree of availability and passability. The proposed approach was applied to modeling the passability and food availability for wild boar and red deer biotopes in the southern spurs of the Bureinsky range in the Russian Far East. The snow accumulation coefficients used in the model were obtained from field surveys carried out in 2016–2018 at 173 sites located on slopes of different exposure and steepness and within different types of plant communities. It has been established that a significant part of the favorable foraging territories of wild boar and deer overlap, that may cause the interspecific competition and increased load on forage biotopes during severe and snowy winters. The model also makes possible to introduce additional parameters such as the energy consumption per movement, composition and quantity of feeds.Описаны принципы биотопического подхода к пространственно-временнóму моделированию высоты и структуры снежного покрова для анализа характеристик зимних местообитаний животных на мезомасштабном уровне. Анализ зимних местообитаний предложено проводить на основе двух параметров, зависящих от высоты и структуры снежного покрова: проходимости и доступности. На примере ландшафтов южных отрогов Буреинского хребта Дальнего Востока выполнено моделирование высоты снежного покрова для кормовых биотопов кабанов и благородных оленей. На основе коэффициентов снегонакопления, полученныx по результатам полевых исследований, с помощью геоинформационных методов проведена экстраполяция значений высоты снежного покрова, свойственных каждому типу кормового биотопа. Площади кормовых биотопов кабана и благородного оленя ранжированы на доступные, труднодоступные и недоступные. Информация о проходимости и доступности пищевых ресурсов в зимний период позволила проанализировать пространственную структуру кормовых биотопов, оценить их разобщённость и предположить возможные пути зимних миграций животных различных видов
Опыт применения высокочастотного георадара для ландшафтной снегомерной съёмки в окрестностях городов Кировск (Хибины) и Апатиты
Get PDFThe results of processing of a profile snow-measuring survey of snow cover in the Khibiny Mountains are presented. The survey was performed during the period of maximum snow accumulation (March of 2020) on the main elements of the landscape: mixed forest on the plain, open woodlands at the bottom of valleys, plateaus, wooded slopes, and upper slopes without woody vegetation. The averaged values of snow storage for different types of the landscapes were obtained for the period of the maximum snow accumulation in the snowy winter of 2019/20. The maximum snow storage (> 700 mm w.e.) was determined for areas on the high plateaus and open woodlands at the bottom of valleys. Minimum snow storage (> 400 mm w.e.) was recorded in areas of mixed forest on the plain and on an ice cover of lakes. Measurements of snow depth were carried out by the standard method (a handspike) and the ground-based radio-echo sounding using georadar with the frequency of 1600 MHz. The accuracy of this method allows measuring of the snow depth with accuracy of 1 cm for a dense snow and 2 cm for a loose one. Thus, the accuracy of measuring the snow depth with the radar is comparable to the accuracy of a handspike. A large number of radar measurements of snow depth on the profiles makes possible to determine the spatial variability of this value and its statistical characteristics. As a result, a vertical gradient of snow accumulation was defined as 25 mm w.e. per 100 m. The smallest spatial variability of snow depth was observed on profiles in the forests on the plain, in woodlands, and on the upper slopes. On profiles with complex relief (plateau, lower slopes), the spatial variability of snow depth is significant – the standard deviation was within limits of 30%. Based on the results of processing the field data, a map of snow storage over the studying area during the period of maximum snow accumulation was constructed. When constructing the map, we took into account the averaged data of the measurements for each type of landscape, the boundaries of woody vegetation, the height, steepness of slopes, and the high-altitude gradient of snow accumulation. It was found that features of the spatial distribution of snow cover were primarily due to the location of natural landscape complexes. The role of changes in snow storages with altitude was found to be insignificant.Исследовано пространственное распределение снежного покрова с помощью высокочастотного георадара в период максимальных снегозапасов в Хибинских горах в многоснежную зиму 2019/20 г. Наблюдения в смешанном лесу, редколесье на дне долин, на плато, залесённых и оголённых склонах показали, что распределение снежного покрова обусловлено прежде всего естественными границами природных ландшафтных комплексов. Изменение снегозапасов с высотой выражено лишь на отдельных протяжённых склонах
Строение и динамика ледника Альдегонда (Западный Шпицберген) по данным повторных георадиолокационных исследований 1999, 2018 и 2019 годов
Get PDFOver the last decades, glaciers on Svalbard were shrinking in response to the current climate change. Most of them decreased in size, area, and surface height with a stable negative or even accelerated changes in the mass balance. Many of them belong to the polythermal type, and as they shrink, their thermal regime can also change significantly depending on the climate and local parameters such as the ice facies distribution, the firn thickness, and others that affect the hydrology and movement of glaciers. Data from repeated GPR surveys in 1999 and 2018–2019 were used to identify changes in the thermal regime of the polythermal Aldegondabreen, Svalbard. The glacier has undergone a significant reduction of its temperate ice core, as a consequence of steadily negative mass balance, decreasing thickness, and the tongue retreat. The results show that over a 19‑year period, the total area of the glacier has decreased by 23.1% (from 6.94 to 5.34 km2), and the total volume of ice – by 36.4% (from 0.437 to 0.278 km3). At the same time, the area of its temperate core has decreased by 32.7% (from 1.196 to 0.804 km2), and the core volume – by 42.5% (from 0.035 to 0.02 km3). In this way, the relative rates of internal glacier changes associated with the warm core exceeded the external changes of the entire glacier. The share of temperate ice in the total volume of the glacier ice decreased from 8% to 7%. The glacier shrinking in response to rise of the air temperature was accompanied by its gradual internal «cooling». In the near future, this can result in a rapid transition of the glacier from a polythermal type into a cold one. Regular repeated geophysical surveys of the internal structure of the Svalbard polythermal glaciers can become an important element in the system of long-term monitoring of changes in climate and the natural environment of the archipelago, along with already existing observations of other sensitive natural indicators such as the size and mass balance.Сравнение данных наземных радиолокационных съёмок 1999 и 2018–2019 гг. политермического ледника Альдегонда на Шпицбергене показывает, что площадь ледника за эти годы сократилась на 23,1%, а объём – на 36,4%. При этом площадь его тёплого ледяного ядра уменьшилась на 32,7%, а его объём – на 42,5%. Сокращение ледника сопровождается его постепенным выхолаживанием, что, вероятно, со временем приведёт к тому, что он превратится из политермического в ледник холодного типа
Моделирование заторов льда в руслах рек (обзор)
Get PDFThe paper gives an overview of the main publications on the subjects of modeling of ice jams in riverbeds with an emphasis on the experience abroad. Different approaches to modeling of ice jams in rivers are considered conceptually together with a wide range of problems which are solved by means of the modeling. The most successful countries and scientific groups in this area of studies are identified and presented in the article. The most-used computer models were determined, and characteristics of them were investigated. When reviewing, the comparative-descriptive method was used. The list of leading publications on the above subjects was analyzed. Relevant literature was selected using the citation databases – RSCI (Russian Science Citation Index), Scopus and Web of Science. Final results of the work are as follows: a wide range of scientific publications on the subjects of the ice jam modeling published for the last 18 years (1999–2017) had been considered. The geography of publications extends from North America up to Eurasia and Japanese islands. A comparative table of the most commonly used computer models together with characteristics of them had been constructed. The most promising areas of development in the field of modeling of the ice jams are shown.Обзор публикаций по проблеме моделирования заторов льда и ледовых процессов на реках показывает важность физического, математического и компьютерного моделирования заторов. Наибольшие преимущества имеет компьютерное моделирование, которое, кроме научного анализа, позволяет представить доступные инструменты анализа организациям, ответственным за принятие решений по предотвращению негативных последствий заторообразования
Химический состав приземного атмосферного аэрозоля в Баренцбурге (архипелаг Шпицберген) по результатам многолетних исследований
Get PDFThe chemical composition (ions, elements, polycyclic aromatic hydrocarbons) of aerosol and gaseous impurities (SO2, HNO3, HCl, NH3) in the surface layer of the atmosphere in Barentsburg, located on the Western Svalbard island (Svalbard archipelago), is analyzed. Atmospheric aerosol and gaseous impurities brought to the Arctic from middle latitudes and deposited on snow and ice not only interact with various natural objects, but also spread to long distances with melting dirty snow and ice. Air sampling was carried out following to methodology adopted by the international networks of the atmospheric monitoring programs in South-East Asia (EANET) and Europe (EMEP). In 2011-2015, the observations of the chemical composition of the atmospheric ground layer were performed daily during the light season (April–September), and monthly from April 2016 to 2018. The largest total ion concentrations were observed in 2011–2012. Seasonal variability of ion concentrations in the aerosol was characterized by high values in the cold period (October–February) and low values in the warm one (May–June). High values of the coefficient of correlation between ions Na+ and Cl− (r = 0,93) as well as between Mg2+ and Cl− (r = 0,81) throughout the year show that the main source of the aerosol is the sea surface. The significant correlation between ions K+, NO3-, NH4+, SO42−, K+, SO42− in the polar night point to the influence of local sources: coal mining at the mine and its3 combustion at thermal power plants. Emission of polycyclic aromatic hydrocarbons and the gaseous impurities (SO2, HNO3) into the atmosphere, especially during the polar night, is also influenced by local sources. Among the elements the maximum enrichment of the aerosol was revealed for As, Cr, Zn, Mo, Cd, Sn, Sb, W, and Pb with a low content of Cd, Sn, Sb, W, and Pb in the coal, sludge and on the underlying surface. On the basis of the elemental composition of the aerosol and the back-trajectory analysis, it was shown that the air masses enriched in heavy metals come to the area of the Barentsburg settlement from middle latitudes.Прослежена межгодовая (2011–2017 гг.) и сезонная (2016–2018 гг.) изменчивость компонентов химического состава (ионы, элементы, полициклические ароматические углеводороды) атмосферного аэрозоля и газообразных примесей (SO2, HNO3, HCl, NH3) в приземной атмосфере западной части Российской Арктики (пос. Баренцбург на Шпицбергене)
Отрицательные аномалии редокс-потенциала в снежном покрове селитебных зон (на примере г. Якутск)
Get PDFOne of the significant environmental factors of the environments of Northern cities is the specificity of the oxygen regime of the atmosphere. The main air pollutants and oxygen absorbents are industrial enterprises and automobile transport. Snow cover serves as a natural accumulator of precipitation and other fall-outs from the atmosphere and, thus, an indicator of atmospheric pollution. The constancy of the ratio of oxygen in the atmospheric air and snow cover allows us qualitative assessing of the change in the concentration of oxygen in the atmosphere during the cold season by the value of the redox potential-Eh of snowmelt waters. In the second half of March 2016–2019, a geochemical study of snow cover was conducted on the territory of the city of Yakutsk and its environs. In areas of the city with a high level of air pollution, the presence of negative anomalies of the redox potential of the snow cover – melt snow waters had been established. It was found that the greatest influence on the decrease in the Eh value of snowmelt water is exerted by dustiness of the air, and the content of chlorides and carbonates. These negative anomalies of the redox potential in snowmelt waters on the territory of the city are associated with technogenic areas of macro- and micro-components of the snow chemical composition, alkaline pH values, and dust emissions into the atmosphere. On the territory of Yakutsk, the values of the redox potential of the snow cover decrease, on average, by 134 mV relative to the background values, while in the areas where polluting objects are located – by 200–250 mV.Установлено формирование отрицательных аномалий редокс-потенциала в снежном покрове селитебных зон. В талых водах снежного покрова эти аномалии чётко коррелируют с загрязнителями окружающей среды и могут использоваться для оценки санитарного состояния зимней атмосферы селитебных и промышленных зон
Изменения и репрезентативность параметров горного оледенения
Get PDFThe study was aimed at analysis of changes in the area Fgl, the number Ngl and statistical parameters of distribution for different aggregates of glaciers over two periods: 1946–1975 and 1976–2005. The determined changes in the above parameters of glaciers located in river basins of the following mountain regions: the North Caucasus (Baksan, Chegem, Cherek, Malka, Teberda, Terek), Alay ridge (Akbura, Isfara, Isfayram, Shahimardan, Sokh), Altay (Aktru, Chuya, Katun) and Pamir (Gunt), are presented in the article. For better reliability of the height parameters of the glacier aggregates at the scale of the river basins, the maximum, minimum and average height values of individual glaciers were weighed by area. The trustworthiness of changes of the weighed height parameters confirms consistency with the linear relationship adopted at the scale of the river basin between the dimensions of the glaciers and the average weighed heights of beginning, end and average altitude of individual glaciers. Definition of the concept and the scale of representativeness of local measurements of glacier mass balance in the WGMS database is the actual glaciological problem. The proposed quantitative substantiation and the results of the selection of a group of representative glaciers are, in general, based on the use of parameters of dynamical state of individual glaciers distributed over several intervals from the minimum to maximum area values. The parameters of each glacier included: total area, volume, maximum and minimum height difference, index of morphological type, average thickness, orientation and slope of the surface. The sequence of determining the composition of a sample of representative glaciers on the example of glaciations in the basins of the Kyzylsu Western (Pamir) and Katun (Altai) rivers is described. Important part of the work was performed to reveal the possibilities to use local values (Ab – ablation/Bs – summer mass balance) measured on a priori reference/representative glaciers in the WGMS database as an additional argument for modeling and calculation of river runoff at the scale of river basins for June–September and other time intervals. Adding of local values of Ab/Bs as a complementary argument to the regression equations for regional calculations of runoff of the rivers of a snow-glacial feeding in the North Caucasus, Pamir-Alai and Altai was found to be efficient in only limited number of cases. The hydrological representation of the glacier is a new characteristic of practical importance for solving problems of hydrology and glaciology in river basins of snow-glacial type of the flow formation, which include almost all Alpine river basins. The method of revealing the hydrological representativeness of local Ab/Bs measurements described in the paper may be used for glaciers from the existing WGMS network.Описано изменение за 1946–2005 гг. статистических характеристик распределения высотных и площадных параметров для совокупностей ледников на Северном Кавказе, Алайском хребте, в бассейнах рек Катунь (Алтай) и Гунт (Памир). Установлены возможность и обоснованность использования локальных измерений абляции/летнего баланса массы на ледниках Джанкуат (Северный Кавказ), Малый Актру (Алтай) и Абрамова (Памиро-Алай) в качестве дополнительного источника информации при расчётах стока рек снегово-ледникового типа питания
Оценка баланса массы ледника Альдегонда (Западный Шпицберген) в 2015–2018 гг. на основе модели ArcticDEM, геодезических и гляциологических данных
Get PDFThe Aldegonda (Aldegondabreen) Glacier, located on the Nordenskjold Land, West Spitsbergen, covers the area of about 6 km2 (in 2018) and does constantly retreat since the very first observations of 1936. In August 2018, a topographic survey of the glacier was carried out. By comparing the results with the ArcticDEM model, built from space images of 2015, the difference in heights of the surface over three years had been calculated. Comparison of this difference with in situ data of glaciological measurements by the ablation stakes, made during the same period 2015–2018, demonstrated a high correlation between them. Considering the almost complete absence of snow cover on the glacier at the end of the summer season, the difference was recalculated into the spatial distribution of the specific mass balance by multiplying the ice density (0.88 g cm−3). Using the empirical dependence of the specific mass balance on the altitude above sea level, the obtained values were extrapolated to that part of the glacier which was not surveyed in 2018. The total loss of the Aldegonda Clacier mass for 2015–2018, calculated on the basis of topographic survey and the ArcticDEM, was estimated as 30.3 million tons (about 10.1 million tons per year). This magnitude gives the value of mean annual specific balance of approximately −1.76 m w.e, which is almost 2.5 times larger modulo than the previously published mean for the period 1936–1990, but close to the values of the early 2000s. Despite the small difference in the values obtained by geodetic and glaciological methods, the measurements does not show a systematic shift relative to each other and demonstrate approximately the same intervals of specific balance from the glacier tongue to its upper reaches (−1.08 ÷ −3.01 m w.e). This makes possible to conclude that the ArcticDEM model has the satisfactory vertical accuracy (both relative and absolute) to study on its basis changes in the surface height of an individual glacier.Путём сравнения результатов топографической съёмки с моделью местности ArcticDEM изучено снижение поверхности ледника Альдегонда за 2015–2018 гг. Потеря массы ледником за три года составила 30,3 млн т, или −1,76 м в.э. Исследование показало возможность применения ArcticDEM для масс-балансовых оценок отдельных ледников
Реакция ледников Полярного Урала на современные изменения климата
Get PDFMonitoring of glacier mass balance is usually focused on analysis of middle and large glaciers, so small glaciers on the verge of extinction remain out of the attention of researchers. Studies of glaciers of the Polar Urals, begun in the mid-twentieth century, present in this respect interesting information. The series of observations of them is the longest among other glaciers of the mountainous regions of the Russian mainland in the polar latitudes. New results of quantitative assessment of changes in the size and mass balance of glaciers in this region are presented. To estimate the geodetic balance of the IGAN Glacier, data from photogeodetic surveys of 1963, data of ground-based DGPS surveys of 2008 and 2018 together with a fragment of the digital elevation model (DEM) of the ArcticDEM v3.0 of 2016 were used. Using these data, the DEM of its surface was calculated as of 1963, 2008, and 2018, and the changes in the glacier volume were estimated for the period from 1963 to 2018, during which the glacier had lost 19.7 million m3 of ice, of which 3.2 million m3 were lost in the last decade. The average decrease in the surface height was 18.94±3.22 m, and the maximum – 53.5±1.0 m. In 1963–2008, the specific massbalance was equal to −317±59 mm w.e./year, while in 2008–2018 −336±61 mm/year. Estimation of changes in the size of 30 glaciers of the Polar Urals made from images of the Sentinel-2 satellite had shown that in 2000– 2018 the glaciers lost 2.02 km2 (about 28%) of the area. In comparison with the period of 1953–2000, the average annual rate of reduction of their area doubled and amounted to 0.112 km2/year (1.54%/year). Magnitudes of the reduction of individual glaciers are not identical. Within the selection of 30 glaciers, they vary from 7.1% (the Terentyev Glacier) to 61.1% (the Oleniy Glacier). The analysis of changes in temperature and precipitation in 2000–2018 allows us making the conclusion that the reason for the accelerated reduction of glaciers in the Polar Urals in these years is the rise of summer air temperature since beginning of the twentieth century by 1.5 °C, to which the lowering of winter precipitation was added in the last decade.По данным фотогеодезических съёмок 1963 г., наземных DGPS‐съёмок 2008 и 2018 гг. и космических снимков оценены изменения геодезического баланса ледника ИГАН и размеров 30 ледников Полярного Урала с 1953 по 2018 г. По сравнению с 1953 г. площадь ледников продолжает сокращаться с возрастающей скоростью; с начала ХХI в. она увеличилась в 2 раза. С 1953 г. ледник ИГАН потерял 19,7 млн м3 льда, его высота в среднем понизилась на 19 м