Global potential and limits of mangrove blue carbon for climate change mitigation

Background

Despite national and international policy organizations’ interest in blue carbon financing for mangrove conservation, there is a lack of investment in payments for ecosystem services from the commercial sector. To encourage future investments and scale up blue carbon projects, it is necessary to address knowledge gaps on the financial return on investment for blue carbon projects.

Goals and Methods

The authors used mangrove aboveground, belowground, and soil organic carbon data published between 2018 and 2020 to model and map the global extent of potential blue carbon credit certification sites, accounting for requirements likeadditionality, decay rates, and buffer credits. To model the profitability of blue carbon projects at potential blue carbon certification sites, the authors calculated return on investment from published data for costs of project establishment and maintenance, projected profits, and current carbon market prices.

Conclusions and Takeaways

About 20% of global mangrove forests qualify for blue carbon financing, which could mitigate 28.7 to 38.9 megatons of carbon dioxide equivalent per year. However, only about 10% of global mangrove forests could be financially profitable as blue carbon projects at current market rates, mitigating 21.6 to 30.8 megatons of carbon dioxide equivalent per year. Indonesia, Myanmar, and Vietnam contain 60% of the total global profitable mangrove sites, highlighting areas where blue carbon projects could have significant climate mitigation effects at a national level.