The race for critical raw materials, such as lithium, cobalt, nickel and rare earth elements, is intensifying as the global economy transitions to renewable energy and electric vehicles. Amid concerns about supply chain security and the environmental impacts of terrestrial mining, deep-sea mining has emerged as a controversial alternative. Proponents argue that mining the ocean floor offers a vast untapped resource base. Critics warn of irreversible damage to fragile ecosystems that remain poorly understood.
What is Deep-Sea Mining?
Deep-sea mining targets mineral-rich areas of the ocean floor, such as:
- Polymetallic Nodules: Found on abyssal plains, particularly in the Clarion-Clipperton Zone (CCZ) between Hawaii and Mexico, these nodules contain nickel, cobalt, manganese, and copper.
- Polymetallic Sulfides: Deposits near hydrothermal vents rich in copper, gold and zinc.
- Cobalt-rich Ferromanganese Crusts: located on underwater mountain ranges, these contain cobalt and rare earth elements.
The International Seabed Authority (ISA), the UN-affiliated body responsible for regulating mining beyond national jurisdictions, has granted over 30 exploration licenses. These allow companies and countries to study potential sites – but not yet to extract resources commercially.
The Case for Deep-Sea Mining
Advocates of deep-sea mining argue that it offers a solution to critical material shortages, reduces reliance on politically unstable regions, and mitigates some of the harmful impacts associated with terrestrial mining. From a geopolitical perspective, deep-sea mining could help diversify sources of critical raw materials, challenging the current dominance of countries like China in the rare earths market.
Socio-environmental trade-offs also feature prominently in the arguments of proponents. Unlike land-based mining, which often devastates ecosystems, displaces communities, and produces significant carbon emissions, mining the ocean floor could potentially avoid deforestation and human displacement. Gerard Barron, CEO of The Metals Company, has positioned deep-sea mining as a “lower-impact” alternative, stating “The choice isn’t whether we mine but where we mine”. For advocates, the ocean floor represents a vast, untapped resource that could address the growing demand for critical minerals without some of the visible destruction caused by terrestrial mining.
The Case Against Deep-Sea Mining
The opposition to deep-sea mining is mounting, led by a coalition of scientists, environmental groups, and nations. In 2021, over 900 marine scientists signed a statement calling for a moratorium, citing insufficient knowledge of deep-sea ecosystems.
- Environmental destruction: Deep-sea habitats are some of the least understood ecosystems on Earth. Mining operations could destroy hydrothermal vents and sediment-dwelling organisms, many of which have never been studied. Plumes of sediment stirred up during mining could spread over vast distances, smothering marine life and disrupting food chains.
- Biodiversity loss: Researchers warn of significant risks to deep-sea species, many of which are endemic to small regions and play critical roles in regulating carbon cycles. Some argue that the ocean floor could hold keys to climate regulation that we do not yet comprehend.
- Unknown long-term effects: Scientists, including Dr. Diva Amon, a prominent deep-sea biologist, emphasize that we lack a baseline understanding of deep-sea ecosystems. “We’re playing with fire in a system that took millions of years to evolve”, she cautions.
Based on the arguments above, the scientists’ statement strongly recommends “that the transition to the exploitation of mineral resource be paused until sufficient and robust scientific information has been obtained to make informed decisions as to whether deep-sea mining can be authorized without significant damage to the marine environment and, if so, under what conditions”.
A Growing Global Moratorium
A number of nations and organizations are calling for a moratorium on deep-sea mining. France became one of the first major economies to advocate a ban, with President Emmanuel Macron stating, “We do not need to start mining the deep sea while we cannot ensure the health of our oceans”. Other countries supporting a halt include Switzerland, Germany, New Zealand, and Chile. So far, 32 countries have announced their support for a moratorium, a precautionary pause, or a ban on deep-sea mining.
On the other side of the debate, nations like Norway and China are pushing forward with exploration, citing the economic opportunities posed by deep-sea resources.
The Unknowns are Too Big To Ignore
Despite the promises of deep-sea mining, the unknowns are staggering. The seabed is the largest and least explored biome on the planet. Its ecosystems are interconnected with global processes, from carbon sequestration to nutrient cycling. Rushing into mining without a full understanding of these systems risk unleashing consequences far beyond localized impacts.
At this stage, deep-sea mining is a high-stakes gamble that could disrupt not just marine ecosystems but planetary systems. As Dr. Sylvia Earle, prominent oceanographer and explorer, has said “Why would we start mining the oceans before we even understand what’s there?”
Science First, Mining Later
The path forward for deep-sea mining must begin with a science-first approach, ensuring that decisions are grounded in robust research and a clear understanding of potential impacts. Comprehensive environmental assessments are essential, with independent studies thoroughly evaluating the risks and consequences of mining in each proposed region. Until this scientific groundwork is laid, global moratoriums and governance frameworks should prevent the transition from exploration to exploitation.
These mechanisms must prioritize ecological preservation and social equity over profit-driven motives. Additionally, significant investments in alternatives—such as recycling critical minerals, advancing material science innovations, and adopting sufficiency strategies to reduce demand—offers viable pathways to delay or potentially eliminate the need for mining the ocean altogether.
As the dialogue intensifies, the answer to whether deep-sea mining is a viable solution remains the same: not yet. Science must take precedence, and humanity must tread cautiously when dealing with the unknown depths of our planet. For now, the price of rushing into the deep might simply be too high.
Shape the Future of Resources at WRF25
The World Resources Forum 2025 (WRF25) conference will bring together decision-makers, experts and innovators to co-develop actionable solutions for sustainable resource strategies. By focusing on three key resource hotspots—the extractive sector, built environment, and consumer and industrial goods—WRF25 aims to spark cross-sector collaboration and drive systemic change.
The path to a better future starts with bold questions, and collaborative solutions.
Will you be part of the solution?
Join us on 2-3 September in Geneva and 4-5 September online!