The Deep Pacific: Seabed Mining and the Battle for the Ocean Floor

Beneath the Pacific's surface lies a resource frontier that could reshape global supply chains—or devastate ecosystems we barely understand. The nations with the most to gain are also those with the most to lose.

Four thousand metres beneath the surface of the Pacific Ocean, in a region known as the Clarion-Clipperton Zone stretching from Hawaii to Mexico, lie trillions of potato-sized nodules scattered across 4.5 million square kilometres of abyssal plain. These polymetallic nodules—composed primarily of manganese, nickel, cobalt, and copper—represent one of the largest untapped mineral deposits on Earth, and their extraction has become the most contentious environmental and geopolitical issue facing the Pacific.

The minerals are not valuable in themselves. They are valuable because they are essential to the technologies that the global energy transition requires. Cobalt for electric vehicle batteries, nickel for battery cathodes, manganese for steel and aluminium alloys, copper for electrical wiring—the green economy's mineral appetite is voracious, and terrestrial sources are concentrated in jurisdictions where mining carries its own environmental, social, and political costs. The Democratic Republic of the Congo produces approximately 70 per cent of the world's cobalt, much of it through artisanal mining involving child labour. Indonesia's nickel laterite mining destroys tropical rainforest. Chile's copper extraction depletes scarce water resources in the Atacama Desert.

Against this backdrop, the deep sea offers an apparent solution: vast mineral resources in areas beyond national jurisdiction, accessible without displacing human communities or destroying surface ecosystems. The International Seabed Authority, established under the 1982 UN Convention on the Law of the Sea, governs mineral extraction in international waters under the principle that seabed resources are "the common heritage of mankind." Since the 1990s, the ISA has issued exploration contracts to state-sponsored entities from over twenty countries, authorising surveys and environmental studies across millions of square kilometres.

But exploration is not extraction, and the transition from one to the other has exposed deep divisions within the Pacific and beyond. The environmental risks of deep-sea mining are poorly understood because the ecosystems at risk are poorly studied. The abyssal plains that harbour polymetallic nodules are not lifeless deserts but complex environments supporting unique biological communities. Sediment plumes generated by mining operations could blanket vast areas, smothering organisms adapted to undisturbed conditions. Noise, light, and chemical pollution could disrupt species whose biology we have barely catalogued.

Pacific Island nations find themselves on both sides of this debate—sometimes simultaneously. Nauru, the Cook Islands, Tonga, and Kiribati hold or have held ISA sponsorship arrangements, hoping to derive revenue from mining operations in areas adjacent to or within their EEZs. Palau, Fiji, and Samoa have called for a moratorium, citing environmental precaution and the inadequacy of current regulatory frameworks. The Pacific Islands Forum has been unable to forge a unified position, reflecting genuine disagreement among its members about the balance between economic opportunity and environmental risk.

The economic argument for mining is compelling for nations with few alternatives. The Cook Islands' Marae Moana—one of the world's largest marine protected areas—also harbours significant seabed mineral deposits. For a nation of 17,000 people with limited agricultural land and a tourism sector vulnerable to external shocks, the prospect of resource revenue is not merely attractive but potentially transformative. Similar calculations apply to Tonga and Kiribati, where government budgets are perpetually constrained and development needs vastly exceed available resources.

The environmental argument against mining is equally compelling but distributed differently. The ecosystems at risk are shared rather than national; their destruction would affect global biodiversity and ocean health in ways that benefit no individual nation. The precautionary principle—the argument that in the absence of adequate scientific understanding, potentially irreversible activities should be postponed—carries particular weight in an environment where recovery timescales are measured in decades or centuries.

The regulatory battle at the ISA has become a proxy war for these competing interests. When Nauru triggered the two-year rule in 2021, it forced the Authority to accelerate regulatory development under conditions that many members and observers considered premature. The resulting negotiations have been contentious, with environmental advocates arguing that the ISA's dual mandate—to facilitate mining and protect the marine environment—creates an inherent conflict of interest.

Corporate actors add further complexity. The Metals Company, backed by Nauru's sponsorship, has been the most aggressive proponent of commercial extraction, arguing that seabed mining is environmentally preferable to terrestrial alternatives and that delay imposes its own costs on the energy transition. Environmental organisations counter that this framing creates a false choice: the alternative to deep-sea mining is not necessarily more terrestrial mining but rather recycling, material efficiency, and technology substitution.

For the Pacific, the seabed mining debate encapsulates a recurring theme: small nations with enormous ocean territories making consequential decisions about global resources under conditions of limited information, constrained capacity, and intense external pressure. The ocean floor, like the ocean surface, is a Pacific commons—a space where the region's nations exercise disproportionate influence over global outcomes. How they exercise that influence on seabed mining may define the Pacific's relationship with the rest of the world for generations.

The stakes could scarcely be higher. If deep-sea mining proceeds and proves environmentally catastrophic, the consequences will be borne primarily by the ocean systems on which Pacific peoples depend. If it is blocked and the energy transition stalls for want of critical minerals, the climate consequences will fall disproportionately on the same low-lying nations whose atolls are already drowning. Between these two risks lies a narrow channel that only careful science, honest negotiation, and genuine respect for Pacific agency can navigate.