Sustainably developing global blue carbon for climate change mitigation and economic benefits through international cooperation

Blue carbon is the carbon stored in vegetated coastal ecosystems (mangroves, salt marshes, seagrass) and is increasingly recognized for climate mitigation and local welfare. Yet a global, long-term assessment of the sustainable development status of blue carbon and the relationships among ecosystem resources, climate-mitigation driving forces, and socioeconomic development capacity remains lacking. The authors construct a Blue Carbon Development Index (BCDI) composed of three subsystems—driving force, resource endowment, and development capacity—to evaluate 136 coastal countries over 24 years and analyze subsystem interrelationships. They further develop a cooperation model to test the feasibility of global cooperation and quantify benefit allocation. Results show an upward trend in BCDI with regional variation and a positive correlation between development capacity and blue carbon resource endowment. Scenario simulations indicate that under a Global Deep Cooperation scenario, countries can raise the global average BCDI, add 2.96 Mt of annual carbon sequestration, and generate $136.34 million in 2030 compared with a Business-As-Usual scenario.