Blue carbon: Knowledge gaps, critical issues, and novel approaches

•Coastal ecosystems are valuable carbon stocks and provide critical ecosystem services including climate benefits.•These 'blue carbon' resources are frequently discussed in terms of carbon markets and climate finance.•Clarity is lacking in the blue carbon discussion over economic and financial issues.•There is also an absence of important social considerations and private sector perspectives.•This paper provides new conceptual understanding and proposes innovative approaches to 'bringing blue carbon to market'.

Blue carbon - the carbon stored and sequestered in mangrove forests, seagrass meadows, and tidal salt marshes - is considered a cost-effective means to achieve positive climate change mitigation and adaptation outcomes. Blue carbon is therefore of considerable interest to the scientific and policy communities, and is frequently discussed in relation to carbon markets and climate finance opportunities. This paper identifies peer-reviewed and 'gray literature' documents that discuss blue carbon in the context of finance and market mechanisms. The document set is analyzed both quantitatively and qualitatively, and the principal scientific, economic, regulatory, social, and management issues that emerge are discussed. The study reveals that (1) the blue carbon literature is dominated by technical and policy commentary, with a dearth of research into practical social considerations and a stark absence of private sector perspectives; (2) there is confusion over the nature and role of important concepts including private and public sector finance and instruments; and (3) understanding of the important issues of investment priorities and risk considerations is also limited. This paper therefore identifies gaps in the blue carbon literature, clarifies critical concepts and issues, and proposes novel pathways for blue carbon research and project development.