For decades, global climate policy treated the ocean as a passive backdrop – vast, resilient, and largely beyond the reach of effective governance. Climate negotiations focused overwhelmingly on reducing greenhouse gas emissions, protecting forests, and transitioning energy systems, while the ocean was assumed to absorb humanity’s excesses without consequence. That assumption has now collapsed. At the most recent UN Climate Change Conference, COP30 in Belém, Brazil, the ocean emerged not as an afterthought, but as a central pillar of climate governance. This shift marks a profound transformation in how the world understands climate risk, responsibility, and survival.
The reasons for this change are rooted in science, politics, and lived reality. The ocean absorbs more than 90 percent of the excess heat generated by greenhouse gas emissions and roughly a quarter of annual carbon dioxide output. This buffering role has spared the planet from even more extreme warming, but it has come at a devastating cost. Rising ocean temperatures, acidification, deoxygenation, collapsing fisheries, coral bleaching, and accelerating coastal erosion are no longer abstract future threats; they are present-day crises. As these impacts intensify, the illusion of an inexhaustible ocean has given way to an urgent recognition of its fragility.
At COP30, this recognition translated into concrete political change. The conference marked the moment when the ocean moved from the margins of climate diplomacy to the mainstream of global climate governance. Ocean issues featured prominently in national climate plans, adaptation frameworks, the follow-up to the first global stocktake under the Paris Agreement, and even the evolving architecture of climate finance. What had once been treated as a niche concern became a shared priority across regions and income levels.
A critical force behind this shift has been the leadership of small island developing states and least developed countries. For these nations, ocean governance is not merely an environmental issue – it is a matter of survival, sovereignty, and justice. Sea-level rise threatens to erase coastlines, contaminate freshwater supplies, undermine food security, and in some cases eliminate entire countries as habitable territories. By framing ocean degradation as an existential crisis rooted in historical emissions and unequal power structures, these states pushed climate negotiations toward a more holistic and morally grounded approach.
This political reframing was evident in COP30’s headline declaration, the “Global Mutirão.” The declaration explicitly links climate change, biodiversity loss, and land and ocean degradation as interconnected crises that demand collective solutions. For the first time at this level, marine ecosystems were recognized not only as victims of climate change, but as essential components of climate stability and sustainable development. This recognition provides governments with the political legitimacy to integrate ocean and coastal priorities into national climate strategies, development plans, and funding proposals.
One of the most significant outcomes of COP30 was the establishment of a new baseline within the UN climate process. For the first time, the official synthesis of national climate plans includes a dedicated section on the ocean. Approximately three-quarters of national plans now reference marine-related actions, including blue carbon ecosystems such as mangroves and seagrasses, offshore renewable energy, fisheries resilience, and the decarbonization of maritime transport. While many of these commitments remain qualitative rather than quantified, the direction of travel is clear. The next phase of climate policy will likely involve measurable ocean-based targets, standardized blue carbon accounting, and explicit investment commitments for coastal communities.
Adaptation also took a significant step forward. Governments adopted the Belém Adaptation Indicators to track progress under the Global Goal on Adaptation. Although these indicators are sector-neutral, their relevance to coastal and marine systems is unmistakable. They encompass ecosystem health, infrastructure resilience, livelihood security, and early-warning systems – all of which are critical for communities living at the ocean-climate interface. Importantly, major climate funds such as the Green Climate Fund, the Global Environment Facility, and the Adaptation Fund have been encouraged to align their financing with these indicators. This alignment could unlock a new generation of bankable ocean adaptation projects, particularly in vulnerable regions that have long struggled to access climate finance.
Financial momentum is already building. The One Ocean Partnership, launched at COP30, aims to mobilize $20 billion by 2030 for coastal resilience, blue carbon ecosystems, and marine protection. Its ambitions extend beyond conservation, targeting the creation of 20 million “blue jobs” and the restoration of 20 million hectares of marine ecosystems worldwide. Even more telling was the announcement by the UN Standing Committee on Finance that its 2026 forum will focus specifically on financing climate action in water systems and the ocean. A decade ago, such a focus would have been politically unthinkable. Today, it signals the emergence of a blue investment agenda within mainstream climate finance.
Parallel to these policy developments, international law has begun to converge with climate science. In 2024, the International Tribunal for the Law of the Sea ruled that greenhouse gas emissions constitute marine pollution under the UN Convention on the Law of the Sea. This interpretation dramatically expands the legal relevance of climate emissions for ocean governance. In 2025, the International Court of Justice went further, affirming that states have a binding legal duty to prevent foreseeable climate harm. Together, these rulings strengthen the legal basis for holding states accountable for climate impacts at sea and along coastlines.
This legal evolution is particularly consequential as the world approaches the next frontier of climate intervention: marine carbon dioxide removal. Techniques such as ocean alkalinity enhancement and large-scale algal cultivation are increasingly discussed as potential tools for achieving net-zero emissions. However, these approaches carry ecological risks and currently exist within a fragmented and inadequate regulatory framework. Without coordinated governance, unilateral experimentation could produce transboundary harm, undermine trust, and fuel geopolitical conflict. The growing legal recognition of climate-related marine obligations may prove essential in managing these emerging risks.
Geopolitically, the rise of ocean-centered climate governance reflects a broader shift in global influence. Traditional power centers no longer dominate climate norm-setting as they once did. At COP30, the voices of small island states, least developed countries, and coastal nations carried unprecedented weight. Even advanced economies are beginning to recognize that sustainable ocean management is not optional. The G20’s establishment of the Oceans 20 group under Brazil’s 2024 presidency underscores this realization, signaling that marine issues now belong firmly within the highest levels of global economic coordination.
Looking ahead, the design of COP31 reinforces expectations of a deepening blue agenda. With Australia and Türkiye set to co-lead the conference and a pre-event gathering planned for a Pacific island state, there is growing optimism that it could become the first truly “blue” COP. If so, ocean-based targets will likely be embedded more deeply in national climate strategies, global stocktake metrics, climate finance rules, and technology transfer systems.
In many respects, the world may be entering a maritime century. The ocean is the planet’s largest carbon sink, the backbone of global trade, a vital source of food and energy, and the front line of climate vulnerability. It is also becoming a domain of strategic competition over data, technology, resources, and legal leverage. As these dynamics intensify, fragmented mandates, outdated treaties, and siloed financing mechanisms are no longer sufficient.
The fate of the climate is inseparable from the fate of the ocean. The question now is not whether ocean governance belongs at the heart of climate policy, but whether global institutions can evolve quickly and equitably enough to protect this critical planetary system. The blue era of climate governance has begun – and its success will help determine the future of life on Earth.
Sonjib Chandra Das is a Staff Correspondent of Blitz.