Marine Carbonate System Observing and mCDR: New Processes, Needs, and Systems

Marine carbon dioxide removal (mCDR) techniques have the potential to remove legacy emitted carbon dioxide from the atmosphere and store it durably in ocean reservoirs. While the ocean’s vast surface area and buffering capacity offer benefits for scaling removal, monitoring remains challenging. This comprehensive review of marine carbonate system observing and monitoring technologies finds that mCDR processes span multiple scales, often at the edges of existing platform and sensing capability. While some mCDR observing and monitoring is possible today, challenges will arise as experiments and operations expand. Leaps forward in assessing the novel scales of mCDR processes will emerge from low-energy, low-cost, highly durable sensors; innovative deployment platforms; cooperative sensing networks; dedicated model validation programs; and decision support tools. This review is intended to serve as a guide to the history, ongoing innovation, and transformative vision of future marine carbonate system observing and monitoring informed by mCDR.