Source: AGU Advances
Today, the world’s ecosystems and oceans absorb about half of anthropogenic emissions while also contributing CO2 from land use, drought, wildfire, and other processes. The uptake of anthropogenic CO2 is expected to slow in the future but by how much? The best tool for projecting future interactions between anthropogenic and natural processes remains Earth System models, which are stubbornly divergent about future carbon fluxes.
Jones et al.  present a massive effort comparing regional budgets, assembled globally, to simulations of carbon stocks and fluxes. To the good, they show that multi-model means generally agree with regional assessments, but concerningly, no one model shows consistent skill across all regions. The authors also find that using skill against assessments in the present is ineffective in increasing predictive skill. While projections of the future carbon cycle are ever more important for policy, they remain a very cloudy crystal ball, informative but still frustratingly imprecise.
Citation: Jones, C. D., Ziehn, T., Anand, J., Bastos, A., Burke, E., Canadell, J. G., et al. (2023). RECCAP2 future component: Consistency and potential for regional assessment to constrain global projections. AGU Advances, 4, e2023AV001024. https://doi.org/10.1029/2023AV001024
—David S. Schimel, Editor, AGU Advances