Enhanced rock weathering involves crushing silicate rocks into fine particles, spreading the rock dust on croplands, and allowing natural chemical reactions between the minerals and atmospheric carbon dioxide to bind carbon in stable mineral forms that can persist for thousands of years while enriching soils with nutrients such as calcium, magnesium and iron.
In a new study published in the journal Communications Sustainability, the team modeled different global adoption pathways for enhanced rock weathering and found that the approach could remove up to about 1 gigaton of carbon from the atmosphere per year by 2100, an amount comparable to the current annual emissions of a large industrialized economy.
The researchers showed that achieving this level of carbon removal depends on rapid and widespread uptake of the practice in the Global South, where warmer and wetter climatic conditions speed up rock weathering reactions and increase the amount of carbon that can be locked away in mineral form each year.
Senior author Chuan Liao, an assistant professor at Cornell University, said that if the technology scales as envisioned, countries in the Global South would eventually contribute the largest share of the carbon removal, and that technology transfer and well-designed global carbon markets could accelerate adoption in these regions while making the distribution of benefits more equitable.
Earlier studies typically assumed that farmers and regions around the world would adopt enhanced rock weathering at the same rate, but the new work introduces staggered adoption patterns, regional time lags and social tipping points that can speed or slow the spread of new mitigation technologies.
The modeling suggests that high-income countries are likely to lead in early deployment of enhanced rock weathering, but that nations such as India and Brazil and other parts of the Global South will overtake them by around 2050 as the practice spreads and local experience grows.
Depending on whether adoption follows a modest or aggressive trajectory, the analysis estimates that enhanced rock weathering could remove between 0.35 and 0.76 gigatons of carbon per year by 2050 and between 0.7 and 1.1 gigatons per year by 2100.
Beyond its climate benefits, the researchers emphasize that enhanced rock weathering can provide significant co-benefits for farmers by supplying key nutrients to soils, potentially reducing the need for synthetic fertilizers, lowering soil acidity and improving crop yields while generating new revenue streams from carbon credits.
Benjamin Z. Houlton, dean of the Cornell University College of Agriculture and Life Sciences and a co-author of the study, said that better scientific predictions of enhanced rock weathering performance are crucial because the practice has strong potential to send carbon profits directly to farmers while helping to decarbonize the global food system.
Lead modeling work by postdoctoral researchers Ying Tu and Radine Rafols drew on historical data for the uptake of other agricultural innovations, including the adoption of fertilizers and irrigation, to create scenarios with early and late adopters across countries and regions and to project both conservative and ambitious futures for the spread of enhanced rock weathering.
Liao noted that expanding access to the practice in the Global South would not only maximize its carbon removal potential but also support smallholder farmers by directing carbon credit revenues to lower income regions and helping to stabilize or increase crop production under a changing climate.
For readers seeking additional background on this work and the broader context for enhanced rock weathering as a climate and agricultural solution, Cornell University has provided a detailed overview in its institutional news channels.
Research Report:Scaling up enhanced rock weathering for equitable climate change mitigation
Related Links
Cornell University
Climate Science News - Modeling, Mitigation Adaptation
| Subscribe Free To Our Daily Newsletters |
| Subscribe Free To Our Daily Newsletters |
