Changes in the thermal state of permafrost under the influence of climatic variations have occurred over the years, but have not reached their maximum. This circumstance significantly increases the risks in fuel and energy complex stability. Everywhere in the Russian Arctic, there is a loss of the bearing capacity in the bases of buildings and structures. The vast majority of the permafrost data are outdated and need to be actualized in the formation of a unified monitoring system. The development of the fuel and energy complex in the Russian Arctic complements the impact of background climate change. As a result of the joint effect of climate warming and large-scale man-made impacts on permafrost, a cumulative effect arises. Its consequences critically accelerate the loss of the stability of frozen foundations, which leads to major accidents of natural–technical systems.
1. Introduction
The regions of Russia located in the Arctic and Subarctic play a key role in the country’s fuel and energy complex. This is because 13% of the world’s oil reserves, 30% of natural gas, and 20% of gas condensate are located in the Russian Arctic
[1]. Russia’s Arctic sector contains about 41% of the region’s total oil reserves and 70% of its gas reserves
[2]. The energy infrastructure of the Russian Arctic, which includes oil and gas deposits and pipelines, plays an important role in the supply of hydrocarbons, not only to Russia, but also to many European countries. Therefore, the stable development of the Russian energy complex today has strategic importance for the economy in the scale of the whole Eurasian region.
One of the main threats to the stable development of the fuel and energy complex in Russia is climate change
[3][4][5]. Over the past thirty years, from 1990 to 2020, the air temperature has been growing in all regions of the Russian Arctic. In total, the average annual temperature of the Arctic Region has increased by 2.4 °C over 30 years (or by 0.8 °C over 10 years)
[6]. The temperature of the permafrost rises more slowly than the air temperature (up to 0.5 °C over 10 years)
[7]. Analysis by region gives slightly smaller gradients: approximately 0.4 °C over 10 years by air and 0.3 °C over 10 years by permafrost
[4].
According to predictions based on various scenarios, here can assume that the high rates of warming will continue to increase in some regions of the Arctic
[8][9]. There is a loss-bearing capacity in the foundations of engineering structures already in the Arctic
[10]; on average, up to 40% of them are deformed to one degree or another
[7]. The estimate predicts potential damage of up to USD 132 billion (total) and ~USD 15 billion for residential infrastructure alone for the Russian Arctic
[4]. Most of the available data on the state of permafrost, including oil and gas field areas and transport communications, are outdated and need updating. With an increase in temperature and thawing of permafrost, the entire overlap between surface and ground water can change
[11]. Epidemiological and environmental threats have increased in the developed areas of the Russian Arctic
[12].
This includes the using of the following nomenclature. Permafrost—that section of frozen ground, below the active layer, which remains permanently below the freezing point; permafrost monitoring—system of observations for control of permafrost condition and dynamics, mostly by measuring soil temperatures and earth surface changes; background monitoring, or BM—permafrost monitoring in natural conditions; geotechnical monitoring, or GTM—permafrost monitoring in built-up areas; energy Infrastructure falls into two general categories—energy production and energy transportation; energy infrastructure—a constellation of the basic facilities for generation and transport of energy, including electricity, oil, natural gas and coal; bearing capacity of a foundation—the maximum load that can be applied on a foundation, before failure or uncontrolled deformations occur; permafrost table—the more or less irregular surface in the ground that marks the upper limit of the permafrost; the active layer—the top layer of soil that thaws during the summer and freezes again during the cold period above the permafrost table; layer of zero annual amplitudes—a layer between the surface of the ground and the point below the surface where the ground is not affected by the temperature oscillations over a year.
Permafrost is the basis of the landscape and natural environment in the Arctic. Therefore, permafrost monitoring is important to assess its current state and development trends, given the prevalent warming scenario. A permafrost monitoring system with a sufficient duration of observation series allows assessing the cyclicality and trends of permafrost processes. Following the climate warming, the degradation of natural landscapes has been observed in the European North and Siberia: temperature of frozen soils rises and an increase in the depth of seasonal thawing is observed
[11][13]. Permafrost monitoring is a comprehensive system of interaction with permafrost, including the observations, analysis, assessment and forecasting of changes in its state, as well as management (if necessary and possible). Alexander Pavlov
[14] proposed the name and basic principles of such monitoring in its modern form, although its foundations were laid by generations of Russian scientists, starting with Mikhail Lomonosov, Alexander Middendorf and Mikhail Sumgin
[15][16]. Lomonosov, in the 18th century, defined permafrost as a natural phenomenon. Mindendorf, in the middle of the 19th century, established the spatial coverage of the permafrost zone and estimated the power of frozen grounds. Sumgin, at the beginning of the 20th century, conducted a systematic survey of the permafrost zone in Russia.
Permafrost resistance to external impact, including climate variability or human factor, depends primarily on the temperature of soils, and on the content and the spread of underground ice in them. The development of cryogenic processes, which are a powerful relief-forming factor, can change natural landscapes in a short time
[11].
2. Development and Findings
The system of permafrost background monitoring (BM) is currently represented in Russia in various ministries and departments, by a limited number of stations and sites of periodic visits. Comparison of the Russian BM with other countries shows that northern countries are developing permafrost monitoring on the basis of research and geological institutions
[4][17]. The USA and Canada made it on the basis of the Geological Surveys; Switzerland and Norway, on the basis of universities under the state program, and China, on the basis of the Academy of Sciences, jointly with manufacturing enterprises. Observations of undisturbed areas are undoubtedly useful, but they do not reflect the state of permafrost in the area of development or subsoil use
[18].
The geotechnical monitoring (GTM) network in Russia is functioning at many industrial, transport and civil facilities. It significantly reduces the risks associated with the interaction of engineering facilities and permafrost. In addition, it prevents the emergence of incidents and significantly reduce operating costs due to timely decisions made on the management of the state of frozen grounds. Meanwhile, the mandatory requirements of such monitoring are far from always being met
[4].
In addition, the disadvantage of the existing geological and technical measures system is the lack of background sites in the geological and technical measures network for studying the temperature regime of permafrost in nature and the dynamics of the development of exogenous processes. Despite the arrangement of geotechnical monitoring at a number of large facilities, as well as in some cities (Yakutsk, Salekhard), the absence of simultaneous background monitoring reduces the efficiency of both
[18][19].
A common disadvantage of the existing BM and GTM is the absence of observations in the hydrological and hydrogeological regime in the territory, the state and characteristics of snow and vegetation, soil moisture in the active layer, and other important indicators of geosystems. Without them, a quantitative forecast on the state of the eternal permafrost, as well as the decision-making process of ensuring the sustainability of facilities, is impossible
[19].
Now, the global permafrost network, authorized by the World Meteorological Organization (WMO) and its associates, consists of two observational components: the Circumpolar Active Layer Monitoring (CALM) and the Thermal State of Permafrost
[20]. International requirements for space-based monitoring of permafrost observables were defined within the IGOS Cryosphere Theme Report at the start of the IPY in 2007
[21].
An integral part of monitoring is not only about observations, but about the analysis of all available data, and primarily, on the foundations of buildings and facilities, and the development of technical solutions for the engineering protection of economic and social facilities; otherwise, they are irrelevant. Such technical solutions are possible only on the basis of a quantitative, scientifically grounded permafrost forecast. Observations, permafrost forecast and development of technical solutions should be carried out on the basis of uniform and tested methods and equipment. However, they have not yet been developed. Besides, the monitoring system still has no structures responsible for forecasting the state of permafrost, and no centers for developing technical solutions to ensure the stability of buildings and engineering facilities on permafrost.