Carbon certification company Isometric has released a draft framework for using computational models to quantify carbon removal from enhanced weathering (EW), designed to allow the nascent technology to scale without sacrificing scientific rigor, opening a 30-day public consultation.
EW—the practice of spreading crushed silicate rock, typically basalt, across agricultural fields to accelerate natural carbon-absorbing chemical reactions—is considered one of the more promising approaches to gigaton-scale carbon dioxide removal (CDR).
In December 2024, Isometric issued what it describes as the world’s first independently certified enhanced weathering credits and has since certified credits across six projects for five suppliers. Now, the core challenge to scaling is Monitoring, Reporting and Verification (MRV).
Current practice relies on dense soil sampling across project fields, a method that is scientifically sound but expensive and therefore impractical at the scale the technology would need to reach to matter for the climate.
Models offer a way to extend the reach of direct measurements by extrapolating from intensively monitored sites across wider deployment areas, but only if constrained by strict validation requirements.
Isometric is explicit that its proposed bar is high, and deliberately so. The draft module requires projects to demonstrate that their model performs against real-world field data at validation and at every subsequent reporting period.
Proprietary models must undergo review by an independent expert panel, with findings made publicly available. No pathway to credits exists that bypasses field measurements entirely, the company underlined.
Relevant: Should We Shift The Way We Think About Enhanced Rock Weathering?
Zeke Hausfather, Climate Research Lead at Frontier, an advance market commitment to purchase more than $1 billion in permanent carbon removal by 2030, welcomed the approach but stressed the importance of keeping measurement central.
“Credible models must also be transparent and open to the broader scientific community to assess and improve,” he was quoted as saying.
The public consultation runs until July 8, and EW suppliers, buyers, and the wider scientific community are invited to participate and provide input to help shape the final version of the module.
Read more: Enhanced Weathering Alliance To Amp Up CDR Scaling Efforts
