This article presents materials on the long-term and seasonal variability of the morphometric characteristics of huge aufeis (taryn) in the Anmangynda River valley in the northeast of Russia. It is shown that the maximum area of the taryn has decreased by 25% and its volume by 33% over the past 60 years. The period of ablation of the ice cluster has decreased by 34 days and the aufeis has moved from the category of migrating formations to the category of seasonal formations.
For two years (2021 and 2022), snow sampling was carried out in the coastal zone of the Onega and Dvina Bays of the White Sea in the period of maximum snow accumulation (March). The snow was analyzed for the content of the major ions (Cl–, ({text{SO}}_{4}^{{2 - }}), Na+, Ca2+, K+); nutrients (phosphorus, silicon, nitrogen), pH, and TDS. The algological composition of the snow cover was also studied. The results showed that the snow was slightly acidic (average pH 5.4). Cl– and Na+ were the main ions in the coastal zone and ({text{SO}}_{4}^{{2 - }}) and Ca2+, in the estuary zone. A high content of marine ions and mineralization were determined near the Paranikha Bay (Dvina Bay), where releases of sea water onto the ice occur annually. Compared to previous studies, in which snow samples were taken in the coastal zone, the concentration of marine ions in the territory under consideration is an order of magnitude higher. The effect of marine aerosols results in that the values of snow cover mineralization can reach 140–680 mg/L. The concentration of dissolved silicon in melt water is higher in the zone influenced by atmospheric emissions from urbanized territories (Arkhangelsk, Novodvinsk, Severodvinsk), as well as near the granite quarry on the coast of Onega Bay. During the study period, 14 taxa of microalgae (species and supraspecific taxa), belonging to the division Bacillariophyta, were found in snow samples. The maximum value of the total number of microalgae (1.293 thousand cells/L) in the snow cover was determined in 2022.
The results of studies of the hydro-cryogenic system “snow on ice–ice–water under ice,” obtained in the winter of 2016/2017 in Lake Baikal are presented. The specific features of the chemistry, the distribution of pH and TDS, the ionic composition, and the main regularities of migration of macro- and microelements of the cryogenic system “snow on ice–ice–under-ice water” are shown.
In the late August 2021, an outburst of the glacier-dammed Lake Spartakovskoe occurred on Bolshevik Island (Severnaya Zemlya). The volume of water discharged from the lake into the Spartak fjord was about 376 ± 21 million m3. The lake bed was filling with water in 2016–2021 much faster than in 2006–2016 because of an increased surface ablation on the glaciers of the drainage basin under the conditions of anomalously warm summer in 2018–2021. The ice dam–lake system changed its state—flow into the Bazovaya River valley can no longer occur.
Degradation of glaciation causes changes in mountain ecosystems, thereby directly influencing human life, and involves changes in the hydrological regime and biogeochemistry of rivers and glacial lakes, thereby affecting the quality and availability of water resources. Issues of assessing the mass balance of glaciers on the northern slope of the Trans-Ili Alatau using Earth remote sensing (ERS) data combined with field studies and measurements are considered.
The features of the hydrological regime of two periglacial lakes with a transgressive development phase, located on the Tavan–Bogdo–Ola mountain range in the Altai Republic, are described based on analysis of the variability of the hydrological and morphometric characteristics of the lakes using satellite images and data from field hydrological observations, which were carried out by the authors in July–August 2021.
The level of snow cover pollution by potentially toxic metals and metalloids is estimated for the area of the Vatinskoe oil field (Khanty-Mansiysk Autonomous Okrug–Yugra). Studies of the filtrate of melted snow and solid-phase precipitation (particles larger than 0.45 µm) showed an increase in Ni and Cr concentrations, suspended fraction, as well as Zn due to the traffic load. The level of pollution increases in areas with a higher concentration of industrial objects.
The article presents the results of instrumental measurements of stem sap flow with the use of sap-flowmeters in the trunks of white fir (Abies nephrolepis), the analysis of the main factors of the process of moisture transport in tree trunks, and the results of modeling hourly series of xylem flow rates. The analysis of factors was made with the use of the method of principal components, and the reproduction of individual series of xylem consumption was based on a multiple linear regression model. The evaluated volume of the transported moisture flux in fir trees over the vegetation period in 2020 varied from 1720 to 5620 L, depending on tree diameter, and the mean daily velocity of stem sap flow in the xylem varied from 0.3 to 1.0 cm/h. Regression analysis was used to find the optimal structure of the empirical model, which includes two predictors—air temperature and humidity. The empirical coefficients of regression equations were determined for each tree based on calibration samples. The results of testing on long enough test samples showed that the model series of xylem discharge on a complete sample (from May to October) for three test trees out of four are close to the measured values: the coefficient of correlation is 0.79–0.88, Nash–Sutcliffe coefficient is 0.62–0.85. The simulation efficiency improves significantly when samples for individual months are used: the correlation coefficient is 0.87‒0.94, the Nash–Sutcliffe coefficient is 0.73‒0.97.
Lake Svyatoe on the Bolshoi Solovetsky Island has been studied. This water body receives water from two lake–canal systems bringing it from the western and eastern parts of the island. The space and time variations of water TDS in the lake and its ionic composition were studied in the period from 2020 to 2023. Season-to-season and annual variations of these characteristics were found, caused by both natural and anthropogenic factors.
The degree of dependence of changes in surface heat and moisture exchange on circulation factors in the Arctic zone of Western Siberia in the period of maximal summer warming was determined. An appreciable northward shift of the average position of +10°C isoline in June within 2.0°–3.5° latitude was recorded in the period 2011–2020 relative to 1961–1990. The dependences of changes in the heat and moisture exchange in the period of maximal summer warming is sufficiently explained by the oscillation of the circulation modes (NAO, AO, PNA, SCAND, EAWR, OST) and an increase in air temperature, which has led to an increase in the ascending vertical fluxes of heat and moisture exchange in the north of Western Siberia from tundra to northern taiga.
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