Enhanced rock weathering (ERW), a process that removes CO2 from the atmosphere for more than 10,000 years, is now available as an accredited carbon removal methodology for companies looking to buy carbon credits on Puro.earth’s voluntary carbon removal marketplace.

ERW is a CO2 removal (CDR) method that accelerates naturally occurring rock weathering that sequesters carbon. The new methodology from Finland’s Puro.earth will enable ERW projects to monetise their CDR activities with ‘CO2 Removal Certificates’, or CORCs. It will allow corporates to purchase these CDR credits for the first time, increasing global ERW capacity by providing early stage financing opportunities.

Enhanced rock weathering accelerates naturally occurring rock weathering that sequesters carbon. (Photo by Waithaya Palee via Getty Images)

ERW accelerates natural weathering by selecting the most reactive rock types, increasing the surface area of the rock by grinding it into fine particles and adding them to soils with optimal climatic conditions. EWR has a variety strengths as a CDR technology: it is globally scalable, has a carbon sequestration potential of more than a billion tonnes per year, involves permanent carbon sequestration of more than 10,000 years with low reversal risk, is not dependent on biomass feedstocks, and can counteract soil acidity and increase soil fertility.

“Puro Standard and the working group have leveraged the latest scientific research on enhanced rock weathering and created a breakthrough carbon crediting methodology that will advance corporations’ climate action,” said Marianne Tikkanen, head of the Carbon Crediting Program at Puro.earth, in a statement. “ERW’s potential to remove atmospheric carbon dioxide at the gigatonne scale makes it a vital solution in the fight against climate change.”