The ocean absorbs over 90% of excess heat and 20-30% of anthropogenic carbon emissions, acting as the world’s climate regulator. Along Africa’s coasts, mangrove and seagrass habitats sequester carbon at a rate four times higher than terrestrial forests, offering nature-based solutions for climate adaptation and mitigation. Additionally, coastal ecosystems including coral reefs provide habitat to several vertebrate and invertebrate species that are a source of livelihood and food to small-scale fisheries. However, rising sea temperatures, acidification, and deoxygenation are degrading these ecosystems, threatening their ability to moderate climate change and provide food security.
The Ocean biodiversity under threat
Coastal and marine fisheries across the globe support the livelihoods of over 600 million people worldwide, including 200 million in coastal communities in Africa. Marine ecosystem health and biodiversity are crucial to food security however, ecosystems are being disrupted by climate-driven changes like increased acidification and marine heatwaves. For example, warming oceans caused 14% of the world’s coral reefs to disappear between 2009 and 2018, which affected African countries like Tanzania and Kenya that depend on reefs for fishing and tourism.
Human Rights and Equity in connection to the Ocean
The connection between the ocean, climate, and biodiversity is deeply intertwined with human rights. Coastal communities in Africa, especially those in Small Island Developing States (SIDS) and Least Developed Countries (LDCs), are facing serious threats from rising sea levels and extreme weather. These communities, which contribute the least to climate change, rely on healthy oceans for their food, income, and cultural traditions. The degradation of ocean ecosystems driven by biodiversity loss, pollution, overfishing, ocean warming, acidification, and broader climate change directly undermines human rights. It threatens the right to self-determination through the overexploitation of marine resources, the right to food and health as pollutants accumulate in marine species and disrupt ecosystems, and the right to security and livelihoods as ocean warming, acidification, and extreme weather events erode coastal infrastructure and resilience. It’s crucial that integrated governance focuses on fairness and upholds the rights of these vulnerable populations.
Where does Africa stand?
Africa is taking bold action on the ocean-climate-biodiversity nexus. The African Union’s Blue Economy Strategy (2019) and Climate Change and Resilient Development Strategy (2022-2032) prioritise nature-based solutions like restoring coastal wetlands to sequester carbon and protect biodiversity. The African Group of Negotiators (AGN) is pushing for more focus on the nexus within the United Nations Framework Convention on Climate Change (UNFCCC) and for the Ocean and Climate Change Dialogue to move from knowledge sharing to implementation.
At the UNFCCC COP26 and Convention on Biological Diversity (CBD) COP16, African voices called for “breaking down silos” between climate, biodiversity and ocean governance. This was further echoed at the African Ministerial Conference on the Environment (AMCEN) in July 2025 that encouraged member states to promote synergies among the Rio Conventions and their corresponding national policies through inter alia, integrated ocean-based targets. The new Agreement on Marine Biodiversity of Areas Beyond National Jurisdiction (BBNJ) provides a framework to protect high seas biodiversity, which aligns with Africa’s call for global cooperation and provides an opportunity for countries to align their ocean-based targets across national policies.
Therefore, what can we do to strengthen integrated ocean action?
Several avenues exist to strengthen integrated ocean action that span cross-cutting areas of science, policy and practice:
- Strengthen Transdisciplinary Research: Invest in research that brings together knowledge of climate, ocean, and biodiversity sciences. The UN Decade of Ocean Science can be used as a platform to study the knowledge issues on the interlinkages of climate and biodiversity and their effects on African coastal communities and economies.
- Streamline Policies: Align national climate and biodiversity strategies under the UNFCCC and CBD to create a “blue thread” of ocean-based solutions. This would also offer a low-cost benefit to African countries when reporting on the progress in achieving their targets.
- Scale Nature-Based Solutions: The restoration of coastal ecosystems such as mangroves, seagrasses, and corals not only increase the capacity of the ocean to sequester carbon but also increase species abundance providing food security and reducing poverty and offering shoreline protection. These solutions can further attract climate finance to benefit vulnerable communities.
- Increase Locally led Marine Protection: Coastal and marine ecosystems under protection show increased resilience against climate shocks and provide refugia for fish stocks to rebound. Prioritizing locally led marine protection through co-development and implementation of governance strategies promotes community buy-in and allows them to benefit from any economic activities that take place in and around the protected areas.
Conclusion
The ocean-climate-biodiversity nexus is not just a scientific concept, it is a lifeline for Africa’s future. By fostering integrated science, policy, and practice, AGNES aims to amplify African leadership in global efforts to protect our oceans. It remains imperative to act now to ensure a healthy, resilient ocean that sustains biodiversity, mitigates climate change, and increases the resilience of coastal communities across the continent.