The study shows that ocean-based climate change adaptation now occupies a stable position in international regulatory and policy agendas. However, the overall framework remains fragmented. Strategic priorities are still categorized in a relatively unclear way across climate, the law of the sea, fisheries and aquaculture, biodiversity, and human rights. At the same time, converging elements can be found in each of these areas, including the precautionary approach, ecosystem-based management, nature-based solutions, marine spatial planning, marine protected areas, impact and vulnerability assessments, the conservation of blue-carbon ecosystems, and adaptive fisheries management.

According to the researchers, this normative convergence has not yet translated into sufficiently rapid and coordinated action. The impacts of climate change on the oceans (warming, acidification, deoxygenation, biodiversity loss, and shifts in fish stocks) require more integrated responses. Strong implementation gaps remain: obligations are often formulated in general terms, political will is limited, financial resources are insufficient, technology transfer remains difficult, and coordination among international institutions is weak.

The paper also highlights several unresolved issues. States tend to focus on aspects that are easier to integrate, including the restoration of coastal ecosystems, blue carbon, and nature-based solutions. Less attention is paid to potential conflicts among objectives: aquaculture development and environmental protection; industrial fishing and biodiversity conservation; food security and the rights of coastal communities; sectoral mandates and the need for integrated ocean governance.

To strengthen ocean-based climate adaptation, the authors identify four key steps. The first concerns the UAE-Belém process on indicators under the United Arab Emirates Framework for Global Climate Resilience, which could translate the global goal on adaptation into clearer targets for the oceans as well. The second is the entry into force of the BBNJ Agreement, which could provide shared standards on marine protected areas, environmental impact assessments, strategic assessments, capacity-building, and the transfer of marine technologies. The third concerns the advisory opinions of the International Court of Justice and the Inter-American Court of Human Rights, which will add to the 2024 ITLOS advisory opinion and could clarify the relationship between climate obligations, protection of the marine environment, biodiversity, and human rights. The fourth is the growing use of climate litigation, which could help make States’ adaptation obligations more precise and enforceable.

The paper concludes that ocean adaptation can no longer be treated as an ancillary or sectoral issue. It must become part of integrated climate governance, capable of linking the resilience of marine ecosystems, the sustainability of ocean economies, and the protection of the rights of the most exposed communities.

Climate change represents a major threat to marine biodiversity, the sustainable use of ocean resources, and the rights of people who depend on the sea for their livelihoods, food security, and culture. Oceans absorb heat and carbon, but they are also among the systems most affected by the climate crisis. Some changes are already irreversible or are likely to persist for centuries.

In this context, adaptation is not only about protecting ecosystems, but also about the ability of human systems to reduce vulnerability and risk. According to the authors, the problem is that international responses have been developed within separate legal regimes. The result is a mosaic of obligations, recommendations, and tools that increasingly recognize the nexus between the ocean, climate, biodiversity, and people, but still struggle to operate coherently.

The research analyzes international law and policy relevant to ocean climate adaptation. The authors examine international agreements, decisions adopted by Conferences of the Parties, recommendations, technical guidelines, and scholarly commentary, focusing on five areas: climate change, the law of the sea, fisheries and aquaculture, nature conservation, and human rights.

The study distinguishes between two dimensions of adaptation. The first concerns natural marine systems and measures aimed at increasing their resilience to climate impacts. The second concerns human systems that depend on the marine environment. In this latter case, the paper focuses on fisheries and aquaculture, which are crucial sectors for food security and for the livelihoods of many coastal communities.

This approach makes it possible to highlight both the points of convergence among different international regimes and potential policy conflicts. The paper does not address mitigation, loss and damage, migration, regional law, or initiatives by non-State actors. The analysis focuses on how to transform a fragmented set of obligations and commitments into a more coherent framework for ocean-based climate adaptation.