Международный полярный год: инженерно-геокриологические и геоэкологические исследования в северных регионах

The third International Polar Year marks the next large stage in 125-year's international cooperation in polar research. One of the tasks of IPY is the estimation of cryolithozone response to climate change. After relatively cold period of 1950-1960-s, the period of air and ground temperature rise starts. Ground temperature rise slows down in the beginning of 1990-s and now general trend of changes in geocryological conditions is not observed, as it substantially relates to the landscape structure. Ground temperature trends in various landscapes are 2-10 times less compared to trends of air temperature change. General climatic and geocryological tendencies show, that in the coming years, probably, the reduction of permafrost distribution will proceed. Geocryological parameters relate to landscape structure and in its turn is affected by warming. Essential increase of seasonal thaw depth, and formation of technogenic thaw bulbs at and near the engineering structures is marked, which in case of high ice content results in activation of hazardous cryogenic processes. The temperature measurements in the boreholes at disturbed sites show highest trends of ground temperature rise, at the same time, steady tendency to restoration of values of geocryological parameters after restoration of a vegetative cover are observed.