A critical analysis of marine carbon sequestration opportunities in South Korea

• DOI: 10.1371/journal.pclm.0000591
• Publication Date: 2025-05-05T17:25:12Z
• Authors: Peter I. Macreadie; Finnley W. R. Ross; Carlos M. Duarte; Ji Won Hong; Ho-Sung Yoon

South Korea has made significant commitments to pursuing marine carbon sequestration [including ‘blue carbon’] initiatives as part of its broader environmental and climate strategies. Specifically, the South Korean government has set a target to sequester 1,362,000 tonnes of CO₂ in the ocean by 2050 as part of its national strategy. Here, leveraging available data, we outline potential measures to achieve this goal, and provide critical insights into the scale and feasibility of marine carbon sequestration initiatives to inform policymakers and industry stakeholders. We investigated a wide range of potential approaches, ranging from traditional blue carbon approaches involving conservation and restoration of seagrass meadows and tidal marshes; to emerging strategies involving seaweed farming and mudflat restoration; to geoengineering interventions involving ocean alkalinity enhancement. Overall, we find that the South Korean Government target is achievable, largely through [in order of low to high abatement scaleability]: mudflat and saltmarsh conservation/restoration, seaweed conservation/restoration, seagrass conservation/restoration, seaweed farming and ocean alkalinity enhancement. However, we stress that our estimates are rudimentary and carry numerous assumptions/risks, and, moreover, carbon offset standards are still under consideration and development for some of these abatement approaches. In terms of ‘readiness to implement’, South Korea is strongest in seaweed carbon sequestration research and application, with a track record of successful restoration of tens of thousands of hectares of seaweed habitats over several decades. A coordinated national strategy will be needed to realise and establish South Korea’s marine carbon sequestration potential, supported by policy and finance. Fortunately, the marine carbon strategies proposed align with the country’s broader initiatives to enhance biodiversity, protect coastlines, and mitigate the impacts of climate change.