The World Maritime University (WMU) has contributed to a new study revealing that the biological carbon pump (BCP) sequesters approximately 2.8 billion tons of carbon annually—equivalent to 10 billion tons of CO₂—locking it away for at least 50 years.
As explained, for comparison, global CO2 emissions from fossil fuel were 36.6 billion tons in 2023 according to the Global Carbon Budget. The researchers estimate that the carbon storage provided by this ecosystem service is worth $545 billion per year in international waters and $383 billion per year within national Exclusive Economic Zones (EEZs), with the total value projected to exceed $2.2 trillion by 2030.
Understanding the biological carbon pump
The BCP can be likened to a bustling underwater metropolis, a city where marine organisms such as phytoplankton, zooplankton, and fish work in harmony to draw CO₂ from the atmosphere and store it in the ocean. Phytoplankton not only absorb CO₂, but also transform it into essential food for other marine life, which ultimately sinks to the depth of the ocean.
This natural process, known as the biological carbon pump, is critical for regulating Earth’s climate by locking carbon away in the ocean, and slowing its return to the atmosphere where it would exacerbate global warming.
The study also highlights that many Large Ocean Island States, such as Micronesia and Kiribati, possess significant ocean carbon within their EEZs and could play a key role in safeguarding this essential climate-regulating service for the global commons.
Establishing regulatory frameworks to protect the environment
The authors call for stronger conservation policies, enhanced financial incentives for lower income countries, and increased international cooperation to protect this critical carbon sink. This can help nations to fulfill their obligations under the new Global Biodiversity Framework which calls for ecosystem-based approaches to effectively protect 30% of the World’s oceans and coasts in marine protected areas, and to manage the rest for biodiversity.
Accounting of ecosystem services ecological, climate, and economic benefits are useful for managing ecosystems and for informing governments on the ecological and socio-economic importance of their natural resources. Damaging nature has a cost for society and its protection requires funding and holistic approaches,
… said lead author and WMU Senior Researcher, Fabio Berzaghi, adding that sequestration time should be clearly stated and scientifically-estimated to provide more transparency and confidence in investments in carbon sequestration projects.
Senior author, WMU Professor Mary Wisz, explained that life in the ocean plays a crucial role in processing and storing carbon, which would otherwise mix back into the atmosphere and trap heat. She stated that, without life in the ocean, atmospheric carbon levels would be about 50% higher than they are today. However, she pointed out that carbon is not absorbed and stored uniformly throughout the ocean. In some areas, it can remain in the water column or sediments for centuries, while in other regions it could return to the surface within a few years or less, depending on ocean movement.
Nations can protect the biological carbon pump within their territories with marine protected areas, marine spatial planning and environmental impact assessments
… said Professor Wisz, highlighting that nations can also support biological carbon pump protection within international waters by ratifying the Biodiversity Beyond National Jurisdiction Treaty, which recognizes the importance of protecting biogeochemical cycles, such as the BCP and the carbon it stores.
In addition to WMU, the international team of scientists includes researchers from IRD in France, the Technical University of Denmark (DTU), the Gulf of Maine Research Institute, and Blue Green Future in the United States.
These findings are poised to inform global climate finance discussions and influence policy debates at upcoming COP climate and biodiversity summits, underscoring the indispensable role of the oceans in climate mitigation.
The work was funded by the OceanICU Horizon Europe project grant agreement no. 101083922 (OceanICU), which aims to understand biological carbon cycling in the ocean.
