Large amounts of soil carbon deposited in permafrost may be released into the atmosphere due to deeper seasonal thawing under the climatic conditions projected for the future. An increase in the volume of the available organic material together with the higher ground temperatures may lead to enhanced emission of greenhouse gasses.

Although in the public imagination the term “permafrost” is often associated with massive ice buried under the ground, it does not imply the presence of the frozen water. Frozen ground may be "dry"; the term "permafrost" refers to any sub-surface materials that remain below 0 °С for at least two consecutive years. Regions where permafrost underlies all or part of the ground surface occupy about 25 per cent of land area in the Northern Hemisphere, of which about 16.7 million km2 is located in north-eastern Eurasia and 10.2 million km2 in North America.

The mathematical formalism of all permafrost models is based on a solution of the Stefan problem. The peculiarity of the problem is the existence of the moving boundaries between the freezing and thawing ground which are the moisture phase change boundaries. The most perfect dynamic (process-based?динамические) models make it possible to calculate the consecutive temporal evolution of many permafrost parameters considering the thermal inertia of permafrost. However, usually it is impossible to realize the advantages of this kind of models for the large territories because of the limited data.

For studying of air temperature sets and precipitations instead of spars data from meteorological stations often use more accessible climatic archives, where primary observations are processed and girded. They are especially convenient in areas, where a meteorological stations network are rare and non-uniform. Various methods of spatial generalization, from interpolation to complex reanalysis are used for construction of net archives. Results have specific features and describe a climate of separate regions with different accuracy.