Permafrost Coasts of Pechora and Kara Seas in Transition: Environmental Forcing Change

Ogorodov, S.A.; Shabanova, N.N.; Bogatova, D.M.; Shabanov, P.A.; Novikova, A.V., and Kazhukalo, G.A., 2024. Permafrost coasts of Pechora and Kara Seas in transition: Environmental forcing change. In: Phillips, M.R.; Al-Naemi, S., and Duarte, C.M. (eds.), Coastlines under Global Change: Proceedings from the International Coastal Symposium (ICS) 2024 (Doha, Qatar). Journal of Coastal Research, Special Issue No. 113, pp. 230-234. Charlotte (North Carolina), ISSN 0749-0208. Two-thirds of the coastline along the Pechora and Kara Seas 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. Environmental forcing changes in key areas along these coastlines have been calculated and analyzed. Across all considered sites, the sum of positive air temperatures has increased statistically significant for the period 1979-2021, with a trend of 7-28°C·day/year. Wind-wave energy potential for the destruction of thermal-abrasion shores also increased statistically substantially at all high-sea sites, ranging from 20-50% over 40 years. Rising temperatures are reshaping the Arctic coastline, with even greater changes anticipated in this century due to diminished sea ice and thawing permafrost. Reduced sea ice coverage leads to more open water, facilitating stronger wave generation by winds and thereby intensifying wave-induced erosion along the coasts of Pechora and Kara Seas. Analysis of multitemporal aerial and space images, along with field observations has revealed a significant increase in erosion rates of coasts featuring bluffs composed of ice-rich sediments, about 1.3-1.5 times higher, as well as the onset of erosion of many accumulative marsh coasts that had previously remained stable throughout the 20 century.