Long-Term Dynamics of Soil Temperature Regime along the Latitude Gradient in the Permafrost Zone of Central Siberia

The long-term dynamics (1960–2022) of the temperature profile in soils of Central Siberia has been restored and analyzed based on data of weather stations. The relationship between the temperature regime of soil in the permafrost zone and the long-term dynamics of winter and summer air temperature are quantified. The current trends in soil temperature regimes along the depth gradient are evaluated in relation to climatic changes in the region. An increase in the mean temperature for each soil layer is typical for all variants of the degree of permafrost compaction. The mean annual soil temperature increases to a depth of 320 cm, and the growth coefficient is 0.66–0.70°C/10 years. The coefficients are maximal (0.67–1.64°C/10 years) in the permafrost zone of the coast of Central Siberia. The mean annual soil temperature correlates with the dynamics of air temperature. The correlation is most significant for the upper soil horizons (r ∼ 0.8) and naturally decreases with the depth of the soil profile. This pattern is most pronounced in the coastal zone of continuous permafrost (>75° N). Predictive temperature profiles of soils have been obtained with reference to permafrost zoning in Central Siberia. The projection of soil temperature regimes until 2050 enables us to predict significant changes in seasonally thawed layers. According to our estimates, the increase in their thickness may be in the range of 3–12 cm/10 years.