Disclosure statement Pep Canadell receives funding from the Australian National Environmental Science Program - Earth Systems and Climate Change Hub Corinne Le Quéré receives funding from the UK Royal Society and from European Union’s Horizon 2020 research and innovation programme under grant agreement Nos. 821003 (4C) and 776810 (VERIFY). Corinne Le Quéré Chairs the French High council on climate and is a member of the UK Climate Change Committee. Glen Peters receives funding from European Union’s Horizon 2020 research and innovation programme under grant agreement Nos. 821003 (4C), 776810 (VERIFY), and 820846 (PARIS REINFORCE). Matthew William Jones receives funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement Nos. 776810 (VERIFY) and 776186 (CHE).