Accumlating paradigm shifts on Arctic marine ecossytems

Climate change is the most pronounced in Arctic where air and seawater temperature is increasing twice faster than elsewhere. The main observed impacts on the Arctic Ocean include a decrease by 40% since 1979 in the extent of the September icepack, and an increase in freshwater water runoff which, combined with modifications in the ocean circulation, increases vertical stratification. The interest by the scientific community for understanding how the Arctic marine ecosystems respond to such changes has been growing exponentially over the last decade, and boosting the pace of discoveries. In this presentation, while focusing on primary production, I will revisit some of the most significant recent paradigm shifts (e.g. the increasing role of picoplankton, possible massive underice production, increasing occurence of fall blooms, shelf-break upwellings) and examine the possible trajectories for microalgae communities in the future Arctic ocean. I will show results from various observational approaches.