Isometric, a scientific registry for durable carbon removal, has issued the world’s first verified ocean alkalinity enhancement (OAE) credits to Cur8, a UK-based carbon removal marketplace, for a pilot project led by Planetary Technologies in Nova Scotia. The credits are based on the permanent removal of 75 tonnes of CO₂, validated under Isometric’s rigorous protocols. OAE works by adding alkaline minerals to the ocean, increasing its capacity to absorb and store atmospheric CO₂ as bicarbonate, which stays locked away for over 10,000 years.

Three buyers—Shopify, Klarna, and British Airways—purchased a total of 625 credits from this pioneering project, which captured carbon by tweaking ocean chemistry. Studies suggest that if scaled globally, ocean alkalinity enhancement could draw down gigatons of CO₂ annually. These first-mover companies are purchasing credits to support project developers in building expertise and achieving commercial scale, highlighting growing momentum around innovative climate technologies essential for meeting net-zero targets.