Carbon Emission from Ice-Rich Permafrost Bluffs: Insights from Coastal Erosion and Sediment Redistribution Estimations, Kharasavey, Kara Sea

Kazhukalo, G.; Belova, N.; Overduin, P.; Ogorodov, S.; Bogatova, D., and Shilova, O., 2024. Carbon emission from ice-rich permafrost bluffs: Insights from coastal erosion and sediment redistribution estimations, Kharasavey, Kara Sea. 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. 458-462. Charlotte (North Carolina), ISSN 0749-0208. In the present study, geospatial data of shoreline change, the volume of eroded sediments and facies-specific organic carbon density were combined to calculate local-scale carbon flux for the Kharasavey key site, Kara Sea. Geochemical analyses of the 97 samples from different facial units along a 9-km coastal bluff gave a mean annual carbon flux (TOCs) value of 656.3 ty-1 or 73 ty-1km-1. Both organic carbon concentrations in Late Pleistocene-Holocene sediments and values of sediments flux are consistent with previous estimates for the Kara Sea and can be extrapolated to similarly composed reaches. Grain-size analysis revealed no substantial longshore transport and potential re-sequestration of carbon northwards of the bluff. These results highlight the importance of carbon loss assessment from ice-rich permafrost bluffs across the entire Arctic coast for further climate change projections.