Léo Lacour’s work focuses on bio-physical interactions, from submesoscale to basin scale, that influence the biological carbon pump. More specifically, he studies phytoplankton phenology, phyto-zoo interactions, particle dynamics, and export/remineralisation processes leading to carbon sequestration in the ocean and climate regulation. He uses Biogeochemical-Argo floats equipped with cutting-edge sensors (e.g. UVP6) and both passive and active remote sensing (ocean colour, lidar) to explore under-sampled polar (Arctic and Southern Ocean) and subpolar environments.