Sébastien works on the scientific algorithms used to derive the MethaneSAT Level 2 products. During his PhD at the University of Toronto, Sébastien experimented with a new algorithm of the Total Carbon Column Observing Network to retrieve vertical profile information of carbon dioxide concentration. He also worked on processing solar spectra from the Eureka (Nunavut, Canada) TCCON site. In a different project, he made use of NASA's ReFRACtor algorithm.