Scaling up enhanced rock weathering for equitable climate change mitigation

Enhanced rock weathering (ERW) is an emerging approach to remove carbon dioxide from the atmosphere while improving soil health and crop productivity. Yet its long-term climate impact remains uncertain due to limited understanding of how adoption will evolve across regions, income groups, and in response to a warming world. Here, we combine historical analogs of technological diffusion with a coupled human–nature feedback model to provide spatially explicit projections of global ERW adoption through 2100. We develop five scenarios reflecting varying levels of policy ambition, societal responsiveness, and implementation capacity. Our results indicate that ERW could remove 0.35-0.76 gigatons of carbon dioxide per year by 2050, and 0.7-1.1 gigatons per year by 2100, with divergent outcomes across scenarios. While high-income countries lead in early deployment, countries like India and Brazil will overtake them by mid-century driven by accelerated uptake and favorable biophysical conditions. The share of carbon removal from low- and lower-middle-income countries is projected to rise from 20–29% in 2040 to ~60% by 2100. These findings highlight ERW’s potential contributions climate mitigation and a more inclusive and equitable transition. By modeling varying responses to climate risk, we underscore how societal dynamics can shape equitable decarbonization pathways globally. Enhanced rock weathering can remove up to 0.76 to 1.1 Gigatons of carbon dioxide per year by 2050 to 2100, with low- and middle-income regions as key contributors, based on projections using technology diffusion analogs and a coupled human–nature feedback model.