In October 2015, she was elected co-chair of Working Group 1 (WGI) of the IPCC, which is the group that "examines the physical science basis".[1] She was the co-ordinating lead author of the paleoclimate chapter in the IPCC Fifth Assessment Report (AR5) cycle.[2] Masson-Delmotte is currently leading IPCC's Working Group One's (WGI) activities for the Sixth Assessment Report (AR6) cycle.[7]