Marine Negative Emission Technologies: A Review of Theory and Applications

Achieving carbon neutrality by 2060 requires coordinated scientific efforts to tackle intensifying climate challenges. To balance environmental conservation with economic growth, emission reductions must be coupled with effective negative emissions strategies. This study outlines the principles of technologies grounded in technical frameworks for achieving ocean-based carbon dioxide removal (CDR) including ocean alkalinity enhancement, artificial upwelling, the marine biological carbon pump, and iron fertilization. By synthesizing domestic and international research, this review comprehensively summarizes applied studies based on diverse theoretical models. Furthermore, it analyzes and compares the distinct challenges of implementation pathways and ecological impact assessments. To advance ocean-based climate mitigation in China, this study evaluates applications of negative carbon technologies, offering strategic insights for their development and identifies persistent uncertainties regarding ecological impacts, the need for region-specific environmental assessments using robust modeling and field data, and a lack of comprehensive techno-economic and socio-legal feasibility studies.