Global distribution, quantification, and valuation of the biological carbon pump. Implications for climate finance, conservation, and ocean management.

Marine organisms, from plankton to fish, provide a wealth of ecosystem services, including carbon sequestration in a process known as the ocean’s biological carbon pump (BCP). The BCP brings carbon from the atmosphere to the ocean depths where it is stored for decades to centuries. Although parts of the ocean’s BCP are under threat from human activities, BCP carbon sequestration rarely features as an objective in efforts to protect ocean spaces. Moreover, although BCP carbon sequestration services could support discussions of conservation and climate finance, its economic value has yet to be estimated in space and time and thus the BCP has not been discussed in relation to the blue economy.We performed a spatial analysis and financial valuation of the carbon pump service in relation to geo-political and management boundaries. We developed a new metric to map and quantify the global ocean’s BCP long-term carbon sequestration accounting for the carbon that remains stored in the ocean’s interior for more than 50 years, what we call 50-year carbon sequestration rate. We show the global spatial patterns and valuation in relation to geopolitical and management boundaries, and highlight options for governance and management. We estimate that, annually, the biological carbon pump adds in the ocean 2.81 Gt of carbon (range 2.44 - 3.53) with a storage time of at least 50 years (±25 years). This ecosystem service is worth US$383 billion/year (range 336 - 471) within all Exclusive Economic Zones, US$545 billion/year (range 471 - 694) in areas beyond national jurisdiction, and US$2.2 trillion (range 1.9 - 2.7; sum of discounted values for 2023-2030). These results quantify the climate and economic importance of the biological carbon pump and the important role of Small Island Developing Nations in carbon sequestration. These findings can support discussions in climate finance and in the COP global stocktake for climate action for developing a more equitable and sustainable ocean economy through opportunities for preserving the climate services of the BCP both nationally and in Areas Beyond National Jurisdiction.