## 4 Discussion
In April, warming to 1-2 \({}^{\circ}\)C was observed along all railway sections, with the warming being greater in more northerly sections. In May, warming to 1-2 \({}^{\circ}\)C was observed along all sections of the railways. In June, the greatest warming was observed along the sections to Salekhard and Yamburg, and northwards and eastwards the anomaly was greater, up to 2.4 \({}^{\circ}\)C. In July, August, and September, on the contrary, the temperature anomalies in the western part of the studied area were greater (up to 0.8-1.4 \({}^{\circ}\)C) than along the eastern sections of the railways. In October, there was a uniform warming of the entire region to 0.8 \({}^{\circ}\)C, and only on the northernmost railway section to Murmansk and Yamburgthe anomaly reached 1.2 \({}^{\circ}\)C. In November, all the sections showed warming between 2 \({}^{\circ}\)C and 2.6 \({}^{\circ}\)C, except for the section to Yamburg, which reached 0.8 \({}^{\circ}\)C. In December, the warming increased from east to west, from 0 \({}^{\circ}\)C to 2.2 \({}^{\circ}\)C on the section to Murmansk in Figure 22. Thus, the regional climate change is very uneven within the year (by month), spatially, and even along each section of the railway separately. Not only the rate, but also the direction of air temperature change varied radically from 1980 to 2021. If in 1980-1999, almost the whole studied area was cooling at a rate from 0 \({}^{\circ}\)C to 0.5 \({}^{\circ}\)C per 10 years. In Figure 23 (except for the Kola Peninsula and Karelia, where warming was 0.2 \({}^{\circ}\)C per 10 years), in 2000-2021, warming was observed everywhere from 0.1 \({}^{\circ}\)C to 0.5 \({}^{\circ}\)C per 10 years and the farther northwards, and it was faster on average in Figure 24.  
Atmospheric precipitation in the studied area was on average 1.8-2.4 in/day, and the average values for 1980-2021 are distributed regularly over the territory, except for the Ob Bay area, where precipitation is less in Figure 17. Difference in mean precipitation between 1980-1999 and 2000-2021 shows that precipitation has increased by 0.06-0.12 in/day on railway sections to Murmansk, by 0.10-0.16 in/day to Arkhangelsk and Salekhard and remained virtually unchanged along the section to Yamburg in Figure 25. These changes are only 5% of the average values, so in the mean this increase is insignificant. However, in areas where average air temperatures have crossed 0 \({}^{\circ}\)C, this may indicate predominantly rain rather than snow, but this requires a joint analysis of air temperature and precipitation changes for individual months. Intra-annual variability shows that the greatest amount of precipitation in the studied area occurs from June to August. The most significant changes between the periods 1980-1999 and 2000-2021 occurred in March in the central part of the studied territory, where precipitation increased by 0.2-0.5 in/day. In May, near Arkhangelsk the increase was 0.5 in/day; in June, along the railway to Salekhard the increase was 0.5-1.0 in/day; in August, at some sections of the Murmansk and Arkhangelsk railways, as well as the railway to Yamburg, the increase was 0.6 in/day; in September, at some sections of the Murmansk and Arkhangelsk railways, as well as the increase of the annual precipitation in the studied area. Figure 22: Average air temperature change (\({}^{\circ}\)C) at 2 m altitude between the periods 1980–1999 and 2000–2021 (difference of average values between these periods) for December. ways, as well as along the railway between Syktyvkar and Salekhard, the increase was 0.4-0.8 in/day. These changes in some months and in some areas are significant, increasing from 25 to 50% of the average values. In addition, the highest growth rate of precipitation was observed exactly in the last 20 years, when it reached 0.15-0.2 in/day per 10 years, i.e., approximately 10% for 10 years along almost all railway sections in Figure 26.  
Average wind speed in the region ranges from 1.0 to 1.5 m/s for 1980-2021.