Sea‐Level Rise Constrains the Carbon Permanence of Global Mangrove Restoration

Mangroves are characterized by high carbon sequestration rates, and future changes in mangrove biomass will be impacted by factors such as climate change, sea level rise, and management strategies. Here, we produce a map of present-day global mangrove aboveground biomass (AGB) based on extensive field observations and satellite data, giving a global mangrove AGB of 1.76 Pg dry matter (DM). After accounting for potential growth to maturity, future changes in climatic and hydrological conditions, possible restoration strategies, and sea-level rise, the global total mangrove AGB is projected to increase by 16.7% under the low-warming scenario (Shared Socioeconomic Pathway 1 and Representative Concentration Pathway 2.6, SSP126) and decrease by 19.3% under the high-warming scenario (SSP585) by 2100. Sea-level rise encroaching upon the growth space of mangroves will cause a biomass loss of 41.6% in the high-warming scenario, whereas restoration strategies would only increase AGB by 2.0%. Our study shows that sea-level rise limits the potential of mangrove restoration to maintain carbon stocks, and regions less constrained by sea-level rise offer greater potential for the long-term permanence.