This paper addresses the insufficient land-sector scenario information in the IPCC's 6th Assessment Report to estimate total carbon dioxide removal (CDR) deployment. Using a new dataset of land-based CDR, the authors show that afforestation and reforestation play a critical near-term role in mitigation, accounting for about 10% of net greenhouse gas emission reductions between 2020 and 2030 in scenarios limiting warming to 1.5°C with limited overshoot. Novel CDR technologies, such as direct air carbon capture and storage (DACCS), scale up significantly by 2050 to balance residual emissions. The study highlights that reducing fossil fuel and deforestation emissions accounts for over 80% of net GHG reductions until net-zero CO2, regardless of climate objective stringency. Regional distributions of emissions and CDR are explored, emphasizing the need for fairness and sustainability considerations in future assessments.

Gaurav Ganti, Thomas Gasser, Mai Bui, Oliver Geden, William F. Lamb, Jan C. Minx, Carl-Friedrich Schleussner, Matthew J. Gidden