In this book the eminent authors analyse the ice cover variability in the Arctic Seas during the 20^th and early 21^st centuries. In the first two chapters, they show that multi-year changes of the sea-ice extent in the Arctic Seas were formed by linear trends and long-term (climatic) cycles lasting about 10, 20 and 60 years. The structure of temporal variability of the western region (Greenland ¿ Kara) differs significantly from the eastern region seas (Laptev and Chukchi). In the latter region, unlike the former area, relatively short-period cycles (up to 10 years) predominate. The linear trends can be related to a super-secular cycle of climatic changes over about 200 years. The most significant of these cycles, lasting 60 years, is most pronounced in the western region seas.

Arctic sea ice as an element of the global climate system.- Long-term changes in Arctic Seas ice extent during the twentieth century.- Variability of sea ice thickness and concentration in the twentieth century.- Consistency among sea ice extent and atmospheric and hydrospheric processes.- Possible causes of changes in climate and in Arctic Seas ice extent.- Assessment of possible changes in air temperature and sea-ice extent in the Arctic Seas in the twenty-first century.- Conclusions.