Home – Home – Jornals – Earth’s Cryosphere 2023 number 4

Data on the interannual dynamics of the seasonal thawing depth in the dominant landscapes of typical tundra at the Marre-Sale geocryological station (western coast of the Yamal Peninsula) are presented. It is shown that drained landscapes have the maximum response to changes in climatic conditions, while wet and boggy landscapes are characterized by the reduced rates of increase in the active layer depth. The slow increase in the depth of seasonal thaw during the current climate warming is explained by the presence of an ice-rich horizon in the upper part of permafrost, thaw subsidence, and an increase in the height of the moss cover. The uneven growth of vegetation, primarily mosses, creates considerable contrasts in the spatial distribution of the active layer depth. For a regional assessment of the thawing depth, the use of its mean weighted value with due account for the share of each landscape in the entire landscape structure of the region is recommended.

Hydrochemical monitoring of inland waters makes it possible to obtain information about their state and to assess the influence of climatic factors on the regime of water reservoirs. In the recent decade, relevance of the research related to the impact of permafrost thaw on the state of small lakes in the Arctic has been growing. The influence of interannual fluctuations in air temperature and precipitation on the ionic composition of lakes has been statistically established for the contents of NO₂, SO₄, and NO₃ ions. Active thermodenudation on the shores of these lakes increases water mineralization levels by an average of 42.8 % and changes the concentrations of major ions Na, Ca, Mg, K, PO₄, and HCO₃.

A study of permafrost and groundwater conditions of the Mahatta Tukulan, Sakha Republic (Yakutia), where thick aquifer talik horizons are common, was carried out. During the first half of July 2021, the water discharge of the Mugur-Taryn Spring was 690 L/s, which is less compared to data from 1973-1974 (770-930 L/s). Current data confirm that the chemical composition of suprapermafrost and interpermafrost groundwater has been stable over the past several decades in the studied sand massifs. The chemical composition of these spring waters is calcium-magnesium bicarbonate, with mineralization of 13-50 mg/dm³. Using field observation data and results of remote sensing data processing, it was determined that the area of the sand massif with a vegetation cover has increased by approximately 18 % during the past 40-50 years. This has led to a decrease in soil temperature, a change in the water heat balance of the massif, and a reduction of water reserves of talik aquifers.

The article offers an analytical solution to the problem of operation of deep seasonal cooling devices (deep SCD) based on the assumption of quasi-stationary regime of soil freezing by the system evaporator. The case of application of the proposed solution for one of the design configurations of a deep SCD on thawed soils with different thermal conductivity under the weather conditions of Salekhard city is considered. We obtained the values of the radius of soil freezing around the evaporator tube as a function of depth at different time intervals of system operation. The present analytical model can be easily applied at the design stage to evaluate and optimize the design of the applied thermal stabilization system in particular geocryological zones for different thermophysical characteristics of soils, taking into account the aggregate state of water in them.

The work is aimed at the theoretical development and modeling of field experiments for a high-resolution geophysical technique of transient electromagnetic sounding in order to substantiate a permafrost monitoring technology. To select the optimal parameters of the sounding system, we established the dynamics of changes in the registered electromotive force in terms of the distance between the signal transmitter and receiver. Based on field temperature measurements at the geophysical test site and the elucidated interrelation between the electrical resistivity and temperature values, we calculated the variations in the resistivity of the near-surface loams and clay loams for the period late January - early April 2022. The dynamics of changes in the boundary between seasonally frozen and underlying rocks was traced. Using the resistivity values calculated from the measured temperatures, we carried out numerical modeling of the electromotive force amplitude to identify the dependence of the signals on the shift of the boundary due to freezing. In addition, approaches were proposed to verification of the results obtained.

In the first decades of the 21st century, the need of changing the paradigm of cryology became obvious. This changing is based on two main approaches. One of them is related to transition from considering the cryosphere as a threat for people to its interpretation as one of the key resources for environmental basis and subsistence. The second approach is based on the need to build a holistic image of the Earth’s cryosphere. Considering the Earth’s cryosphere as a complex system, consisting of cold layers of atmosphere, glaciosphere and subterranean permafrost, brings us to the need for analysis of previous terms identifying object areas that study the world of cold. Ideas about the cryosphere and cryology were formulated in 1974. Modern interpretation of the object and the subject of research was the result of many long-term disputes. Currently, the term “geocryology” remains to be used as a synonym for science of permafrost. However, while building a holistic image of the Earth’s cryosphere, it is necessary to take into account the properties and state of the entire object as a whole and create new terms and concepts that can reflect the expanding contexts of studying cryogenic processes, their ontological hierarchy, system connections, etc. In this situation, the philosophy of science is designed to become a kind of source of generation of new images, concepts, and meanings.

This paper describes the milestones in the scientific career and outreach activities of Vladimir Romanovich Alekseev, an outstanding researcher of Siberian nature. V.R. Alekseev, Professor, Doctor of Geography, Merited Scientist of the Russian Federation, is a principal researcher at the Melnikov Permafrost Institute and an honorary member of the Russian Geographical Society.

This paper describes the milestones in the scientific and pedagogical activity of one of the outstanding scientists in the field of permafrost engineering L.N. Khrustalev, Honored Inventor of the Komi ASSR, Merited Scientist of the Russian Federation, Doctor of Technical Sciences, Honored Professor of Lomonosov Moscow State University.