He has been involved in campaigns and data analyses related to air quality in urban environments (LISAIR, PARISFOG, EM25, MEGAPOLI) and to climate studies (AMMA, ACCESS, PARCS) using active remote sensing observations to discuss aerosol ageing processes and their mixing state. He has participated to the validation of the spaceborne CALIOP lidar on CALIPSO satellite. His current research focuses on the understanding of key processes related to aerosols in the Arctic region (transport and processing, ageing, deposition processes, interaction with clouds, radiative impacts) through a synergy between modeling (WRF-Chem mesoscale online transport chemistry model) and observations (ANR-CLIMSLIP, EU-ACCESS, EU-ECLIPSE, EU-ICE-ARC, PARCS, EQUIPEX-IAOOS, CNES-EECLAT, ERA-Planet iCUPE).