## 4 Discussion  
In this section, we discuss only those results which, from our point of view, are the most significant for consideration by railway operators. [PERSON] and [PERSON] [42] analyzed climatic changes in air temperature, precipitation, and wind speed in this region. The authors showed that there were significant changes in these parameters between the periods 1980-2000 and 2001-2021. The strongest increase in temperature was observed for November and April, indicating that there was a shift in the time boundaries of the seasons--a later start and an early end of winter. It was revealed that in 2001-2021 the temperature increased most rapidly in the offshore area of the Barents and Kara Seas and this growth was accelerated. We have shown that the detected increase in the amount of precipitation is associated with a significant change in atmospheric circulation in the studied area. In the summer season and in September, there was an increase in the west wind within this territory. In the winter season of 2001-2021, there was an increase in the south wind in the Barents and Kara Seas as compared to 1980-2000. [PERSON] and [PERSON] [43] found an increase in upper 1.5 m soil temperatures of about 0.5 \({}^{\circ}\)C in 2001-2021 as compared to 1980-2000 in the west of the studied area. This may lead to the reduction and even complete disappearance of the island permafrost on the Kola Peninsula, where average soil temperatures increased almost everywhere in 2001-2021 to +3 \({}^{\circ}\)C and more. In 2001-2021, an accelerating increase in soil temperature also began in the northeast of the western part of the Russian Arctic. There was a decrease in snow cover thickness in the west and east of the studied area in 2001-2021 as compared to 1980-2000. In the west of the studied area, there was also a significant reduction in the area of snow cover in November and April. An increase in specific humidity at 2 m altitude began in the west of the studied territory, and especially over the White Sea in 1980-2000. In 2001-2021, the increase in air humidity spread to the center and the east of the studied region with the highest growth rate over the waters of the seas, and this growth occurred with acceleration. These changes can be explained by the increasing influence of the North Atlantic on this territory and this process can be called \"Atlantification\" of the climate of the western part of the Russian Arctic. This phenomenon may lead to an increase in the number, strength, and duration of extreme weather events in this area [43]. Our research confirms that the warming of this area is significant and occurs in the direction from southwest to northeast [61]. The railway section from Syktyvkar to Salekhard and the section to Yamburg over the past two decades are in an area where average annual air temperatures remain below 0 \({}^{\circ}\)C in Figure 10. This means that these sections are operated under difficult weather and climatic conditions for all 12 months (as positive air temperature here is on average only from May to September), and the average monthly air temperature reaches from \(-20\)\({}^{\circ}\)C to \(-22\)\({}^{\circ}\)C in winter. Warming of the regional climate will occur along these sections, which will lead to thawing of permafrost, change of hydrological characteristics of numerous rivers, lakes, wetlands and may negatively affect the stability of railway tracks and bridges. Air temperatures along these railways increased by an average of 0.4-0.6 \({}^{\circ}\)C between 1980-1999 and 2000-2021. Comparing these two periods, in January, the warming up to 1.0-1.5 \({}^{\circ}\)C was observed along the section to Murmansk and Arkhangelsk, warming up to 0.5 \({}^{\circ}\)C was observed along the section to Salekhard, and the cooling of 1-2 \({}^{\circ}\)C was observed on the section to Yamburg. In February, warming up to 0.8 \({}^{\circ}\)C was observed only on the section to Murmansk. In March, warming to 1 \({}^{\circ}\)C was observed only on the section to Yamburg.