Hashim et al. (2025): Mineral formation during shipboard ocean alkalinity enhancement experiments in the North Atlantic
Mohammed S. Hashim, Lukas Marx, Frieder Klein, Chloe L. Dean, Emily Burdige, Matthew Hayden, Daniel C. McCorkle and Adam V. Subhas, IN: Biogeosciences, https://bg.copernicus.org/articles/22/7149/2025/bg-22-7149-2025.html
Ocean alkalinity enhancement (OAE) is a carbon dioxide (CO₂) removal approach that involves the addition of alkaline substances to the marine environment to increase seawater buffering capacity and allow it to absorb more atmospheric CO₂. Increasing seawater alkalinity leads to an increase in the saturation state (Ω) with respect to several minerals, which may trigger mineral precipitation, consuming the added alkalinity and thus decreasing the overall efficiency of OAE. To explore mineral formation due to alkalinity addition, the authors present results from shipboard experiments in which an aqueous solution of NaOH was added to unfiltered seawater collected from the surface ocean in the Sargasso Sea.