Climate policies for carbon neutrality should not rely on the uncertain increase of carbon stocks in existing forests

• DOI: 10.1088/1748-9326/ad34e8
• Publication Date: 2024-03-18T22:23:46Z
• Authors: Caspar TJ Roebroek; Luca Caporaso; Ramdane Alkama; Gregory Duveiller; Edouard L Davin; Sonia I Seneviratne; Alessandro Cescatti
• Keywords: Carbon neutrality; Carbon fibers; Neutrality

Abstract The international community, through treaties such as the Paris agreement, aims to limit climate change well below 2 °C, which implies reaching carbon neutrality around second half of century. In current calculations underpinning various roadmaps toward neutrality, a major component is steady or even expanding terrestrial sink, supported by an increase global forest biomass. However, recent research has challenged this view. Here we developed framework that assesses potential equilibrium biomass under different scenarios. Results show warming storage in aboveground gradually shifts higher latitudes and intensity disturbance regimes increases significantly almost everywhere. CO fertilization stands out most uncertain process, with methods estimation leading diverging results 155 PgC above ground at equilibrium. Overall, assuming sum human pressures (e.g. wood extraction) does not over time, total cover trend fertilisation it currently estimated from satellite proxy observations remains, have reached (or are very close reaching) peak storage. short term, where increased assumed act quicker than growth potential, forests might instead source, will require more effort decarbonization previously estimated. Therefore, nature-based solution mitigate brings uncertainties risks thought.