Symposium: Pathways Toward Responsible Marine Carbon Dioxide Removal
Our recent symposium brought together researchers, policymakers, innovators, and industry to explore how marine carbon dioxide removal (mCDR) could develop responsibly in the coming decades. Against the backdrop of growing interest—and growing public concern—around geo-engineering, the meeting highlighted both the promise and the complexity of mCDR as part of broader climate action.
The event opened with an introduction by Dr. Cale Miller (lead of the seed project on pathways toward responsible mCDR), who noted that public attitudes toward geo-engineering remain sceptical, even as major reports—such as the newly released EMB assessment—emphasise the need to better understand the feasibility, risks, and governance of mCDR approaches. Cale stressed the importance of independent verification, impact assessment, and strong collaboration between academia and industry. This set the stage for the proposed seed project “Pathways toward responsible mCDR,” which aims to explore how a socially embedded and environmentally sound scale-up could be achieved by 2050.
A central theme of the symposium was co-production of knowledge, highlighted by Dr. Miranda Boettcher (Utrecht University / SWP Berlin). She outlined why traditional “linear” models—where science simply delivers evidence for policymakers—are insufficient for technologies as value-laden and uncertain as mCDR. Instead, she argued for participatory, transdisciplinary approaches that make underlying assumptions explicit, broaden the solution space, and strengthen societal legitimacy. Drawing on examples from the CDRmare programme, Boettcher showed how co-designed assessment frameworks and participatory foresight can help navigate questions of feasibility, desirability, and governance.
On the policy side, Martijn van de Sande (RVO) presented the forthcoming Innovation Programme Carbon Removal (IPKV), part of the Dutch government’s growing engagement with CDR. The programme—funded through the national climate fund—will support R&D, early-stage pilots, and the development of enabling conditions such as MRV, environmental assessment, and social embeddedness. Martijn also outlined upcoming funding instruments and opportunities for consortia, emphasising the need to build a national CDR innovation ecosystem.
Innovation at the technology frontier was illustrated by Dr. Matteo Gazzani (Utrecht University) and Kathryn Maunders (Kestrel), who presented a new concept coupling Ocean Thermal Energy Conversion (OTEC) with CO₂ removal and deep-ocean storage. While promising from an energy-efficiency standpoint, the approach also raises ecological, technical, and legal questions, demonstrating the importance of early governance and impact assessment.
Finally, Zamin Syed (SeaO2) shared insights from a small public-perception study, underscoring both the high level of concern about climate change and the very low familiarity with mCDR. The findings reinforced a key conclusion of the symposium: transparent communication and sustained community engagement are essential. Participants also noted widespread confusion in media and public discourse—particularly around terminology such as CDR, CCS, and geo-engineering—highlighting the need for a clear communication guide to support journalists, policymakers, and local communities.
Across all discussions, participants recognised that the ocean is already a crowded and contested space, and that responsible mCDR requires navigating scientific uncertainty, regulatory gaps, and societal values. The symposium made clear that co-production, robust MRV, and thoughtful communication and policy design will be central to any credible pathway forward.
