Crushed Rock on Cropland Shows Promise for Carbon Removal

By Blake Jackson

Crushing silicate rocks and spreading the dust on cropland may sound simple, but researchers say the process known as enhanced rock weathering could play a meaningful role in reducing atmospheric carbon dioxide.

When finely ground rock is applied to soil, it reacts naturally with carbon dioxide, locking carbon into stable mineral forms that can remain for thousands of years. At the same time, the minerals released into the soil can improve fertility, increase yields, and potentially boost farm income.

A study modeled how enhanced rock weathering might expand globally over time. The researchers estimate the practice could remove up to about one gigaton of carbon annually by 2100 comparable to the yearly emissions of a large, industrialized nation.

However, widespread adoption, especially in the Global South where warm and wet climates speed weathering reactions, will be critical.

“If this were to be scaled, the Global South would eventually contribute more, and tech transfer and global carbon markets could accelerate adoption in these regions while also making adoption more equitable,” said senior author Chuan Liao, assistant professor in the Ashley School of Global Development and the Environment, part of the College of Agriculture and Life Sciences (CALS).

“Previous research assumed a uniform adoption across regions. Our major contribution in this study is to model these trajectories in a more realistic way.”

Unlike earlier projections, the study incorporates staggered adoption patterns, regional delays, and social tipping points that could accelerate uptake. Private companies such as Microsoft and Stripe have already invested in the approach as part of their carbon removal strategies.

“We need to sharpen scientific predictions of enhanced rock weathering, because it has amazing potential to drive carbon profits directly into farmers’ pocketbooks,” said Benjamin Z. Houlton, the Ronald P. Lynch Dean of CALS.

“Faster global warming is likely to increase pressure on policymakers and farmers to adopt this technology in a more aggressive way,” Liao said.

Photo Credit: gettyimages-zoran-zeremski