Gauri Gupta
The urgent need for climate transition has increased the profile of deep-sea mining (DSM) as a possible source of the metals necessary for a transition to renewables. The need for cobalt, nickel, manganese, copper and rare earth elements, necessary for batteries, wind turbines, and electric vehicles, is growing as more governments commit to carbon neutrality by mid-century. Yet, DSM illuminates a profound paradox: in the effort to respond to the harms of warming the atmosphere to help save the planet, humanity may cause an even larger catastrophic consequence in many of the most poorly understood parts of the planet which include abyssal plains, hydrothermal vent zones and seamounts in the deep sea.
As the debates of policy making evolve, the question is not just whether DSM can supply valuable metals in the future, but also if the ecological, regulatory and even geopolitical costs to practice DSM negate the ideals of sustainability. The scientific evidence and a desire for global engagement show that DSM is already embroiled in conflicts of power imbalance, incomplete governance structures and disproportionate vulnerability of states involved in the practice.
These demonstrate the lasting impacts on the environment of seabed disturbance. The Clarion-Clipperton Zone (CCZ), which covers a large region of 4.5 million km² in the Pacific Ocean between Hawaii and Mexico, is recognized as the most dense studied region on earth for polymetallic nodules. In 1979 in an area designated as a test mine area, large swaths of seabed were removed. In 2023 when scientists returned to investigate the site, there had been no recovery of the seabed, even after 44 years. There were still no signs of sessile organisms (i.e., corals and sponges), patterns of sedimentation had changed, as compared to unaffected areas, and the complexity of the ecosystem was quite simplified, compared to undisturbed areas. The
damage is still present as seabed habitat has recovered on geological timeframes, rather than human timeframes. This puts forward the question that does commercial seabed mining fit with the environmental law precautionary principle? (Natural History Museum, 2025). The biodiversity at stake is not trivial. A survey of the CCZ conducted in 2023 identified more than 5,500 species of metazoans, with 92% of them new to science, and most only observed once (i.e., they are rare and fragile) (Rabone et al., Curr. Biol. 2023).
The newly identified species are mostly invertebrates, including polychaete worms, crustaceans, and sponges, which represent complex ecological webs that are key to nutrient recycling and carbon sequestration. Mining operations could destroy these organisms before their ecological functions, or potential biomedical or industrial applications are even known.
Despite this ecological uncertainty, several states and corporations are advancing DSM agendas. China is the largest holder of ISA exploration contracts, which aligns with its strategy to acquire critical minerals while seeking to operate outside supply chains that are dependent on others. Nauru, a Small Island Developing State (SIDS), has invoked the “two-year rule” of the United Nations Convention on the Law of the Sea (UNCLOS), effectively pushing the ISA to finalise regulations on exploitation.
This move is linked to Nauru’s partnership with The Metals Company, a Canadian corporation seeking to commercialise the extraction of polymetallic nodules. Norway has permitted seabed mining in the Arctic in its Extended Continental Shelf, claiming it will lead on environmentally sustainable extraction to support Europe’s energy transition. At the same time, while the U.S. is not a party to UNCLOS, it is supporting DSM research with U.S. private companies, such as Lockheed Martin, because domestic rare earth supplies are not part of a Chinese supply chain. In addition, countries such as Palau, France, Chile, and Costa Rica are calling for moratoria or precautionary pauses, in part because we lack
scientific knowledge about long-term impacts, and there is a risk of irreversible harm to the world’s shared nature (ISA, 2023).
It is clear that DSM has the potential to recreate long-standing structures of inequitable access to resources on land in a geomorphic environment. Wealthy industrial states with technology and finance are advancing contract and regulatory frameworks, while vulnerable coastal states face the greatest exposure to ecological harm.
A 2025 PLOS One study suggested that DSM could exacerbate negative environmental impact indicators (biodiversity loss, water quality assessment and stress on ecosystems) by as much as 13%, much of which will be taken by coastal communities and SIDS economically dependent upon fisheries and tourism. Insurance and business liability for those risks are estimated to increase by 11%, demonstrating that the risks are. being externalized to less powerful stakeholders. (University of British Columbia, 2025).
From a comparative standpoint, the prospect of an abundance of resources provided by deep-sea mining is also complex. A significant study showed that nodules have heavy rare earth elements (HREE) at concentrations of 26% of total rare earth oxides in the Clarion-Clipperton Zone (CCZ), while terrestrial mines like Mountain Pass mine in the United States contain less than 1%.
This indicates that DSM could provide some minerals in higher concentrations. However, unlike terrestrial mines that disturb smaller local land uses, DSM will disturb significant vast areas of seafloor, which generates sediment plumes that can smother filter-feeding organisms and transport toxic metals for hundreds of kilometers from the mining site. These sediment plumes can affect pelagic ecosystems as well as benthic ecosystems and disturbance of food webs to fish species that are commercially important. (Hein et al., Ore Geology Reviews, 2013).
The project failed in 2019 after a campaign of environmental protest, legal challenges to the operationalization of the project, and lack of financing, resulting in the exploiter leaving the PNG government with total liabilities of over USD 120 million. Local communities expressed a fear of the impacts on fisheries as well as social and spiritual connections to the sea, and raised concerns about a lack of effective consultation. (Childs, Marine Policy, 2020). Governance challenges exacerbate DSM. The International Seabed Authority (ISA), created under UNCLOS to regulate seabed resources as the “common heritage of mankind,” has been criticised for a lack of transparency and insufficient scientific oversight.
Independent reviews of the ISA’s DeepData platform found that more than 20% of the records were duplicative, taxonomic data was often incomplete, and contractors frequently did not provide baseline environmental information. The lack of transparency makes it more difficult for developing states or civil society to independently assess the impacts of the operations (Pew Charitable Trusts, 2023).
As oversight becomes limited, the chances of capture by mineral interests increase, calling into question the efficacy of DSM governance in protecting ocean sustainability. Critically, DSM also exposes a “green paradox”: that solutions for climate mitigation may become drivers of new environmental degradation. Mining is presented as a necessity for achieving net-zero, but modelling shows that there are alternatives.
The recycling of lithium, cobalt, and nickel from end-of-life batteries proposes the potential of meeting 30–40% of demand by 2040 if the required infrastructure were deployed. In parallel, advances in battery chemistry are decreasing the need for cobalt, namely with lithium-iron-phosphate (LFP) batteries already being used in electric vehicles on a wide scale. Policies supporting the circular economy, if properly implemented, will postpone or eliminate the need for DSM in the coming decades (IEA 2023). The mining lobby has therefore minimised these opportunities and framed DSM as the idea of inevitability rather than a choice.
In this regard, the difference between the agendas of states is stark. Resource-rich states, including China and Norway, emphasize national security, their industrial competitiveness, and their leadership in energy transition. They balance supporting mining with retaining the benefits of mining firms to sustain revenue. To some extent SIDS such as Nauru, even in their vulnerability, can identify ways to access revenue with mining firms, to advance short-term financial goals and protect their national interests, laying bare the challenges creating a difficult balance to the dilemma of small economies. Conversely, France, Chile and Costa Rica are concerned about environmental justice and intergenerational equity.
Their non-consensus reveals fault lines in global governance: While some states hold that the seabed is a global commons that we should conserve, other states see it as a frontier for extraction of resources. This also creates a dilemma on the philosophical dimensions: can sustainability exist to permit the destruction of ecosystems that it is clear we will probably never understand?
Ultimately, the paradox of deep-sea mining is in the bloom and bane it offers. Whilst presented as a core initiative in the green transition, it is occurring in policy regimes distinguished by far-reaching fragmentation, a lack of transparency, and insufficient precautionary standards and measures. Governance frameworks are reactive, not anticipatory, privileging technological advance over ecological restraint.
Gaps in baseline data, liability, and equitable benefit sharing remain significant and allow uncertainty to continue to be externalised onto already vulnerable ecosystems. The broader irony is that mechanisms created to aid in sustainability may normalise an ongoing cycle of extraction, which actively detracts from the durable ecological foundation for resilience. In the absence of a radical change in governance, DSM risks becoming a classic case study of environmental law failing to bridge the steep ambition and stewardship.
References
1. Childs, J. (2020). Extracting accountability: The global politics of deep-sea mining in Papua New Guinea. Marine Policy, 117, 103939. https://doi.org/10.1016/j.marpol.2020.103939
2. Hein, J. R., Mizell, K., Koschinsky, A., & Conrad, T. A. (2013). Deep-ocean mineral deposits as a source of critical metals for high- and green-technology applications: Comparison with land-based resources. Ore Geology Reviews, 51, 1–14. https://doi.org/10.1016/j.oregeorev.2012.12.001
3. International Energy Agency (IEA). (2023). The Role of Critical Minerals in Clean Energy Transitions. Paris: IEA. https://www.iea.org/reports/the-role-of-critical-minerals-in-clean-energy-transitions
4. International Seabed Authority (ISA). (2023). Deep-seabed mining: Status of exploration and regulatory developments. Kingston, Jamaica: ISA. https://isa.org.jm
5. Natural History Museum. (2025). Deep-sea mining: What are the environmental risks? London: Natural History Museum.https://www.nhm.ac.uk/discover/deep-sea-mining.html
6. Pew Charitable Trusts. (2023). Analysis of the ISA’s DeepData database reveals transparency and data quality issues. Washington, DC: Pew Charitable Trusts. https://www.pewtrusts.org
7. Rabone, M., et al. (2023). High levels of species novelty in the Clarion-Clipperton Zone: Implications for deep-sea mining. Current Biology, 33(12), 1–12. https://doi.org/10.1016/j.cub.2023.03.056
8. University of British Columbia. (2025). Environmental and socioeconomic risks of deep-sea mining: A quantitative assessment. PLOS ONE, 20(4), e0299874. https://doi.org/10.1371/journal.pone.0299874
About the contributor: Gauri Gupta is pursuing a Master’s degree in International Studies at Stella Maris College, Chennai. She holds a Bachelor’s degree in Mathematics and is enrolled in the Data Science program at IIT Madras. She is a fellow of DFPGYF Diplomacy, Foreign Policy & Geopolitics Youth Fellowship- Cohort 2.0.
Disclaimer: All views expressed in the article belong solely to the author and not necessarily to the organisation.
Read more at IMPRI:
Losing Ground to the Sun: How Solar Expansion is Displacing Rain-fed Farming in Karnataka
Unequal Field: Examining Gender Disparity in Agriculture
Acknowledgement: This article was posted by Shivashish Narayan, a visiting researcher at IMPRI.
