Researchers at the University of Tasmania are calling for a shift in how ocean alkalinity enhancement (OAE) is studied and deployed. Instead of chasing global gigatonne-scale carbon removal, they argue small-scale projects tied to local emissions could deliver measurable CO2 storage and be easier to verify. The new paper in Nature Reviews Earth & Environment points to concrete examples like using silicate waste from wastewater treatment or running electrochemical alkalinity addition on excess wind power. OAE works by adding alkaline material to seawater, which lowers acidity and converts CO2 into bicarbonate ions that can remain stored for millennia. The chemistry is well understood, but the study stresses that sourcing, distribution, and local environmental impacts are not. Trace metals, turbidity, and contact with the atmosphere all need to be tested at small scale before scaling up. For anyone tracking carbon dioxide removal, this is a useful reality check on a method often talked about in futuristic terms.
