The Impact of Modern Climate Changes on the Microalgal Assemblages in the Surface Sediments of the Subpolar North Atlantic

New data have been obtained on the taxonomic composition of microalgal assemblages (dinocysts and diatoms) from surface sediments collected in the Norwegian-Greenland Basin (NGB) in 2016‒2021 as part of the Shirshov Institute of Oceanology expedition program “European Arctic: Geological Record of Environmental and Climatic Changes.” The comparison with thanatocoenoses from the database samples collected prior to 2008 showed that microfossil assemblages from sediments retrieved in 2016‒2021 primarily from the zone influenced by the Arctic and Polar fronts include species that were previously characteristic of stations located further south and southeast. The differences in the taxonomic composition of dinocyst assemblages from the open parts of the NGB are primarily due to a slight increase in the proportion of the species Operculodinium centrocarpum against the background of a certain decrease in the abundance of Nematosphaeropsis labyrinthus cysts. A total of 80 species of diatoms have been identified within the diatom assemblages, dominated by thermophilic planktonic forms such as Asteromphalus robustus, Actinoptychus senarius, Coscinodiscus asteromphalus, and C. radiatus. Their distribution boundary has shifted northward compared to data from the turn of the 21st century.