Blue carbon accounting is the way forward

Blue carbon’ has only been a part of our vocabulary since 2009 after the UN report Blue Carbon. The role of healthy oceans in binding carbon. The term emerged in the movement to implement the blue economy, at the same time as the concepts of ‘blue growth’, ‘blue biotechnologies’, and ‘blue bonds’. 

It refers to the CO2 absorbed and stored by marine and coastal ecosystems. In open waters, phytoplankton plays an important role for the sequestration of carbon while the bottom of the sea ensures a key function of its storage resulting from the decomposition of plants and animals.

The same phenomenon exists along the coast where CO2 contributes to the anabolism of plants to produce biomass through photosynthesis. Seagrass meadows, tidal marshes and mangroves are the three major blue carbon ecosystems given their sequestration and storage capabilities.

©EU GCCA+ Suriname Harvey Lisse/Climate Tracker 

In 2015, only mangroves were recorded in the intended national determined contributions (INDC) for the preparation of the Paris agreement. Today, the tendency is to expand the list to other blue carbon ecosystems as the importance for climate change mitigation is gaining increasing attention in coastal countries. 
Thus, Cabo Verde has recently announced that it will include seagrasses in its NDC. In Mauritania, the large marine protected area of the National Park of the Banc d’Arguin is contributing to 20 % to the achievement of the country’s NDC through the seagrass beds of the park, with an estimated value of USD 9 billion, and annual operating costs of only about USD 1.5 million: a very high return on investment!

Despite the significant contribution of coastal ecosystems to the climate change mitigation process, no country has yet put in place a formal blue carbon  assessment and accounting mechanism. Currently, assessments are carried out on an ad hoc basis, and generally concern marine protected areas to highlight their importance. The focus of these assessments is no longer in terms of maintaining biodiversity, but in terms of combating the effects of climate change, which is much more likely to attract funding.

In this regard, the United Nations Economic Commission for Africa (UNECA) launched an initiative in 2020, the Blue Economy Valuation Toolkit, to report on the contribution of blue ecosystems to the development of the blue economy in African countries. The evaluation tool, adaptable to all ACP countries, as well as others, makes it possible to account for all the services produced by blue ecosystems in a relatively simple and inexpensive way. 

More sophisticated accounting systems are under development, such as the UN System of Environmental-Economic Accounting (SEEA), which integrates economic and environmental data to provide a more comprehensive and multipurpose view of the interrelationships between the economy and the environment. 
Efforts should be made in the short term to a obtain a baseline evaluation of the blue carbon of coastal ecosystems, as well as the monitoring of its annual evolution based on the change of the size of blue carbon ecosystems and their ecological or health conditions.