Trade-offs in land-based carbon removal measures under 1.5 °C and 2 °C futures

Xin Zhao; Bryan K Mignone; Marshall A Wise; Haewon C McJeon

doi:10.1038/s41467-024-46575-3

Trade-offs in land-based carbon removal measures under 1.5 °C and 2 °C futures

Nat Commun. 2024 Mar 14;15(1):2297. doi: 10.1038/s41467-024-46575-3.

Authors

Xin Zhao¹, Bryan K Mignone², Marshall A Wise³, Haewon C McJeon^{3

4}

Affiliations

¹ Joint Global Change Research Institute, Pacific Northwest National Laboratory, 5825 University Research Ct, College Park, MD, USA. xin.zhao@pnnl.gov.
² ExxonMobil Technology and Engineering Company, Annandale, NJ, USA.
³ Joint Global Change Research Institute, Pacific Northwest National Laboratory, 5825 University Research Ct, College Park, MD, USA.
⁴ KAIST Graduate School of Green Growth & Sustainability, Daejeon, Republic of Korea.

Abstract

Land-based carbon removals, specifically afforestation/reforestation and bioenergy with carbon capture and storage (BECCS), vary widely in 1.5 °C and 2 °C scenarios generated by integrated assessment models. Because underlying drivers are difficult to assess, we use a well-known integrated assessment model, GCAM, to demonstrate that land-based carbon removals are sensitive to the strength and scope of land-based mitigation policies. We find that while cumulative afforestation/reforestation and BECCS deployment are inversely related, they are both typically part of cost-effective mitigation pathways, with forestry options deployed earlier. While the CO₂ removal intensity (removal per unit land) of BECCS is typically higher than afforestation/reforestation over long time horizons, the BECCS removal intensity is sensitive to feedstock and technology choices whereas the afforestation/reforestation removal intensity is sensitive to land policy choices. Finally, we find a generally positive relationship between agricultural prices and removal effectiveness of land-based mitigation, suggesting that some trade-offs may be difficult to avoid.