Mathieu Ardyna is a biological oceanographer interested in understanding phytoplankton dynamics in polar environments. His main research focuses on how environnemental drivers and changes are altering phytoplankton phenology, productivity and structure. In both polar regions (i.e., the Arctic and Southern oceans), climate change is drastically affecting the interplay between the atmosphere, the cryosphere and the oceans. His recent work, conducted with collaborators, shows how these fragile polar ecosystems are responding to warmer, more acidic and longer sea-ice free oceans by combining satellite, field and autonomous platform observations.