Negative emissions to mitigate Earth system risks

Journal article

Most climate policies are designed under a deterministic Earth system and their climate implications evaluated ex-post. Approaches that incorporate uncertainty ex-ante to anticipate Earth system risks remain underexplored. Here, we derive global climate strategies with an ex-ante approach, employing an integrated assessment framework that embeds estimates of physical uncertainty obtained through Bayesian fusion of Earth system models’ and observations’ data. These ex-ante strategies mitigate risks in the Earth system through precautionary measures unseen with the ex-post approach, in cost-benefit analysis and cost-effective implementations of various Earth system targets. Net-zero CO2 emissions must typically be reached a decade earlier, which can require up to a doubling of the near-term carbon price. Importantly, sustained and possibly century-long net-negative emissions must be planned for, albeit not to overshoot targets as in traditional scenarios but to mitigate long-term Earth system risks. This heightens the challenge faced by humanity to build a safe future within Earth system boundaries.

Authors: Gasser, T; Rezai, A; Cheritel, C; Baklanov, A; Obersteiner, M

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Nature Research
• Journal: Nature Communications
• Publication date: 2026-02-26
• Acceptance date: 2026-02-09
• DOI: 10.1038/s41467-026-69896-x
• EISSN: 2041-1723
• ISSN: 2041-1723
• Language: English
• Keywords: Earth (classical element); Overshoot (microwave communication); Climate change; Climate system; Implementation; Earth observation; Earth system science; System dynamics