Fig 1.
Overview of blue carbon dioxide removal approaches.
Various approaches are brought forward to enhance the biological carbon uptake in coastal to open ocean ecosystems.
Fig 2.
Systemic effects of ecosystem management.
Ecosystem degradation currently causes emissions (purple). Ecosystem protection and conservation avoids further degradation and conserves carbon reservoirs to avoid future carbon emissions (light blue). Ecosystem restoration returns the ecosystems to their natural state and reduces current emissions (blue). Finally, ecosystem expansion and management can enhance the natural carbon uptake and create anthropogenic carbon removal (dark blue).
Fig 3.
Overview over the key steps for carbon accounting.
Suggested steps to be taken for improved carbon accounting in the context of blueCDR. Note the iterative process of carbon credit value determination and the central role of monitoring and evaluation.
Table 1.
Overview of challenges in marine ecosystem-based CDR measures from the coast to the open ocean, and suggestion of possible ways forward.