Coastal blue carbon is known as the carbon stored in tidal wetland ecosystems. It is kept within soil, living biomass and non-living biomass carbon pools. Coastal blue carbon is a subset of blue carbon that also includes ocean blue carbon, which represents carbon stored in open ocean carbon pools. Blue carbon science is advancing to support policymakers with credible scientific information to make sound decisions relating to the sustainable use of coastal and marine resources. Scientists from research organizations and universities are continuously improving their understanding, hence reducing uncertainties around the fate of blue carbon. -- By Daniel Murdiyarso, a principal scientist at the Center for International Forestry Research (CIFOR).