ИСТИНА

Two-thirds length of Pechora and Kara seas coastline consists of ice-rich permafrost deposits. The dynamic of these coasts is forced mainly by the change of natural environment induced by the global warming. For key areas on the coasts of Pechora and Kara seas environmental forcing changes have been calculated and analyzed. Restored long-term series of temperature, wind speed and direction; the dates of the beginning and end of the ice-free period at hydrometeorological stations were obtained. Calculations of the variability of the temperature and wave-energy components were performed. At all the stations considered, the sum of positive air temperatures increased statistically significantly over the period 1979–2021 with trend 8-12°С per year. It has been established that at all the considered stations of the coastal-shelf zone of the Pechora-Kara sector of the Russian Arctic, the duration of the ice-free period increased statistically significantly over the period with trend 10-25 days per 10 years. Wind-wave energy potential for the destruction of thermal-abrasion shores also increased statistically substantially at all high sea stations, about 20-50% for 40 years. Rising temperatures are altering the arctic coastline and much larger changes are projected to occur during this century as a result of reduced sea ice, thawing permafrost. Less extensive sea ice creates more open water, allowing stronger wave generation by winds, thus increasing wave-induced erosion along Pechora and Kara seas coast. Analysis of multitemporal aerial and space images and field observations have shown considerable increase in erosion rates of coasts with bluffs composed by ice-rich sediments, about 1,3-1,5 times, as well as the start of erosion of many accumulative marsh coasts that have remained stable in the XX century.