ИСТИНА

There has been a noticeable deterioration of the permafrost-ecological and engineering-geocryological situation in recent decades.This retrogression is associated with changes in the natural environment and man-made impact. The data of long-term monitoring observations of the permafrost temperature indicate a tendency towards an increase in temperature. It leads to instabilities of the upper, icy horizons of permafrost, which is the reason for the intensification of engineering-cryogenic processes. Cryogenic processes developing in urban areas of the permafrost zone often differ from those who develop under natural conditions: they proceed more intensively or fade out under the influence of anthropogenic factors. Sometimes, new cryogenic processes and phenomena occur in place where it has not previously been observed. Taken together, these processes can be called engineering-cryogenic. We organized field studies of engineering cryogenic processes at urbanized centers on permafrost, such as: Vorkuta, Norilsk, Salekhard, Labytnangi, Yakutsk, etc. According to the results of the research, was created a map of engineering-cryogenic processes developing in the settlements of the Russian cryolithozone. It was revealed that increasing snowiness of winters activates dangerous processes that adversely affect the infrastructure: man-made warming and flooding of soils. It caused by the formation of man-made snow dumps (located at the same places every year) and leak in the city communications. Field studies revealed that about 200 dumps in Norilsk have height of 2.5 m and more. It extremely reduces the winter cooling of these local areas, adversely affects temperature of the frozen soils and lower bearing capacity of frozen piles. The development of engineering-cryogenic processes in the cryolithozone results in deformations of buildings and infrastructure: about 60% of the facilities in Vorkuta, Igarka, more than 30% in Dudinka, almost 25% in Norilsk, 80-90% of buildings and structures in the Far Eastern national settlements of the North, almost 90% of small dams of the frozen type on river objects. This work was supported by the RFBR project 18-05-60080 "Dangerous nival-glacial and cryogenic processes and their impact on the infrastructure in the Arctic".