Symposium on the ICJ Climate Change Advisory Opinion: What it Means for Land-based Mining in the Green Energy Transition (Part I)

[Digvijay Rewatkar is an LLM candidate at Harvard Law School and an international lawyer with seven years of experience. The views expressed here are those of the author and do not reflect the views of his affiliations. This post was drafted before he commenced his course at Harvard Law School.]

The Advisory Opinion (AO) of the International Court of Justice (ICJ) on Climate Change was delivered on 23 July 2025. The AO takes progressive steps to clarify the applicable law, legal obligations, and responsibilities of States and consequences for non-compliance concerning climate change obligations. While there are many strands to the AO, which in due course will be deconstructed, the focus of this piece is on the effect this AO will have on the discourse concerning mining for the green energy transition. The key proposition for the proponents of land-based and deep-sea mining includes the secure and predictable supply of materials, such as lithium, copper, cobalt, nickel, manganese and rare earth elements required for building the technologies, including electric vehicles, battery storage systems, solar grids, and windmills.  Most opponents of seabed mining have highlighted that the supply of minerals remains sufficient from land-based sources, thereby negating the need for opening a new frontier of extraction in the deep seabed. Proponents of seabed mining argue that it has the least impact on the environment in comparison to land-based mining, and yields higher grades and larger quantities of minerals for comparable amounts of extracted ore. There appears to be merit in both positions; however, to what extent does the ICJ AO on Climate Change question these propositions and create a sense of urgency for action to address humanity’s carbon addiction?

In my view, the ICJ AO has struck a delicate balance between these two mining propositions for fulfilling the demand for minerals for the green energy transition. While the ICJ makes no express reference to land-based mining, it articulates its view of greenhouse gas emissions (GHGs) in the context of fossil fuels. The carbon intensity and contribution of fossil fuel, in an energy starved world, to climate change is now unequivocally established through its reference to the reports of the Intergovernmental Panel on Climate Change (IPCC) as the best available science (para. 74). Further, the ICJ through a careful reading of the legal obligations of states has now articulated a pathway for the adjudication and implementation of international obligations concerning climate change within domestic jurisdictions. This also includes the responsibility of states, owing to their due diligence obligations, concerning the conduct of private actors within their jurisdiction and control. This was made explicitly clear in the case of fossil fuels when the court said, 

‘Failure of a State to take appropriate action to protect the climate system from GHG emissions — including through fossil fuel production, fossil fuel consumption, the granting of fossil fuel exploration licenses or the provision of fossil fuel subsidies — may constitute an internationally wrongful act which is attributable to that State.’ (para. 427)

The ICJ clarifies that states breach international law not simply by emitting greenhouse gases, but by failing to fulfil legal obligations to prevent harm to the climate system from such emissions. This raises the question, could the same line of reasoning be applied to land-based and seabed mining, which offer the promise of minerals for the green transition? This is important since the AO must represent an inflection point in humanity’s relationship with the extractive sectors, and not represent a mere transfer of pollution or emissions from one source to another.

An articulation of such obligations in the context of GHG emissions from land-based mining (in this part) is aimed at bringing nuance to the understanding of the trade-offs that will necessarily have to be made in realising the obligations concerning the protection of the climate system. Part II of the blog concerning seabed mining will assess the emissions and legal obligations in the same light.

The Legal Obligations of States vis-à-vis Land-based Mining

The inquiry begins with the identification of directly relevant applicable law in this case. The court opined that, 

“[…] the UNFCCC being a “framework convention”, and in view of the general character of the obligations contained therein, the subsequent decisions by the parties — including decisions adopting protocols and agreements under the UNFCCC — are intended to interpret or give substance to obligations in the UNFCCC.” (emphasis added) (para 195)

This means that the REDD+ Framework, which emerged from the subsequent decisions of the UNFCCC COP 19 (decisions 2/CP.13, 1/CP.16 and 2/CP.17) and is implemented by article 5 of the Paris Agreement – is therefore a directly relevant applicable law. It encourages the parties,

‘to take action to implement and support […] policy approaches and positive incentives for activities relating to reducing emissions from deforestation and forest degradation, and the role of conservation, sustainable management of forests and enhancement of forest carbon stocks in developing countries […]’.

REDD+ primarily aims at the implementation of activities by national governments to reduce human pressure on forests that result in greenhouse gas emissions at the national level and calls on to address the drivers of deforestation and forest degradation. As the data suggests and without attempting to assign individual responsibility, it is evident that land-based mining, as a driver for deforestation and forest degradation, has been unabated and is likely to expand with the demands of the green transition.

Further, the deleterious effects of land-based mining are linked to the marine environment, too. The obligations under Part XII of the UNCLOS concerning the protection of the marine environment also become relevant. In this regard, article 194 directs states to take all measures to prevent, reduce, and control pollution of the marine environment from any source and ensure that such pollution arising from activities under their jurisdiction and control does not spread beyond areas over which states exercise sovereign rights. This is closely linked to the obligation of states under article 207 to adopt laws and regulations to prevent, reduce, and control such pollution from land-based sources, and article 213, which calls upon states to implement international rules and standards in this regard, but also to enforce their laws. Overall, a combined reading of these provisions suggests that while states are under an obligation of conduct to adopt such laws and regulations, there is a directly linked obligation of result; in other words, to also achieve such prevention, reduction, and control through the enforcement of its environmental protection laws, mining laws, forestry laws, and effluent control laws.

Risks From Land-based Mining vis-à-vis GHG Emissions

Extractive industries significantly impact the environment through landscape degradation, waste, and climate change. The green transition concerns the transition from fuels like coal and oil to renewables, but also carries the risk of potential overexploitation of metallic minerals and resulting environmental harm. In 2020, mineral materials contributed about 15% of global GHG emissions. Although this is not far off from GHG emissions from the Oil and Gas sector, which is also responsible for 15% of global GHG emissions. The problem lies downstream, where the use of the oil and gas results in another 40% of emissions.

By analogy, the logic applicable to fossil fuels must apply to land-based mining and for emissions caused by it, especially the customary law obligations of preventing significant harm to the environment. The AO made it clear that subsequent agreements and decisions of states parties under the UNFCCC framework, including the Paris Agreement, also constitute directly relevant applicable law. Further, AO clarified that the states are under an obligation to enhance carbon sinks in order to reduce GHG emissions (para. 268). In this regard, the REDD+ Framework under the Paris Agreement, which recognises the role of forests in the climate system, especially in the absorption of carbon dioxide, and which can become a source of GHG emissions when destroyed or damaged. 

According to a study by the World Resource Institute, mining has increasingly pushed into forests around the world, especially tropical primary rainforests and protected areas. For instance, in Brazil, mining leases, concessions, and exploration permits cover 1.65 million km² of land, of which 60% is located in the Amazon forest. Land-based mining has been responsible for the loss of 1.4 million hectares of tree cover between 2001 and 2020, releasing 36 million tonnes of carbon dioxide equivalent per year into the atmosphere (this does not include the lost capacity of the forests to sequester carbon). In the case of Indonesia, research suggests that the extent of deforestation associated with nickel mines nearly doubled, and concluded that concerted resources to mitigate against deforestation are therefore needed. Further, research indicates that nickel mining, a key battery metal, has an environmental footprint that may be up to 500 times greater than previously estimated, leading to an underestimation of its environmental impact, especially for products like batteries. Biomass, both flora and fauna, losses vary significantly by mine, with many cases showing substantial unreported carbon emissions compared to other Scope 1 and 2 emissions from nickel extraction and processing. It is widely acknowledged that mining is one of the major drivers of land-cover change, having significant implications on biodiversity and ecosystem functioning. Take, for instance, the impact on the Kafue River in Zambia resulting from a breach in a tailings dam (consisting of 50 million litres of concentrated acid waste), which affected large stretches of the river, creating dead zones.

The effects of such deforestation are not just limited to the lithosphere and the atmosphere but also impinge the hydrosphere [In accordance with the IPCC definition of ‘climate system’ adopted by the ICJ ( para. 75). The National Atmospheric and Oceanic Agency (NOAA) of the United States posits that 80% of pollution to the marine environment comes from the land. This is, for instance, well documented in the case of Nickel mining in Indonesia and the toxic effects of such land-based mining run-off on the marine ecosystem (Also see). The situation is similar in the Democratic Republic of Congo, where deforestation remains unabated and rivers get heavily contaminated from the mining discharges, causing the transfer of pollution to downstream land areas and the sea. This raises the question as to what the obligations of states are vis-à-vis such land-based mining, specifically in the context of the AO. 

Mitigating These Risks Through the Advisory Opinion

The states in this regard have a duty to prevent the risk of significant harm to the environment, given that the risk of harm from unabated deforestation is both probable and foreseeable. The corresponding obligation of conduct or due diligence of states in this regard remains a stringent one. This follows that the states must objectively mitigate the deforestation through appropriate rules and measures informed by best available scientific and technical information, along with the relevant procedural obligations concerning risk and impact assessment or notification of the proposed land-based mining activity affecting forests at appropriate forums, such as under the REDD+ framework (paras 295-299).

By design, the obligations under REDD+ and the associated due diligence obligations will be part of the Nationally Determined Contributions (NDCs) of the mining state. The ICJ in this regard recognised the obligation of result of states under Art. 4 of the Paris Agreement to prepare, communicate and maintain NDCs, it linked its obligation of conduct in so far as each successive NDC must reflect its highest possible ambition of reducing emissions from deforestation, in order to realize the objectives of the Paris Agreement i.e. the 1.5ºC target (para 240). Therefore, in an ideal world, we must be causing less, not more deforestation. 

However, the ICJ doesn’t view these obligations as onerous, and nuances it further, should states adhere to their due diligence obligations. Clearly, there is a way to move away from past practices and minimize environmental damage from land-based mining, for instance, by following the “forest-smart mining” framework developed by the World Bank. Alternatively, it’s also possible to create policies based on best available science, an optimum mix of energy for each state depending upon its context, circumstances, and demands. However, any such other sources of energy, for instance minerals needed for the green transition, need to adhere to similar or higher standards as set out by the ICJ in this AO.

Part II will make an analogous analysis of the GHG emissions from seabed mining, the obligations of states in that regard, and the means of mitigating such risks. The intention to view both avenues of mining together is to understand the latent environmental costs and the institutional setup available to manage them. 

Conclusion

It is apparent that there is the Good, the Bad, and the Ugly associated with both fossil fuels and land-based mining. However and, as the Court in its wisdom has enlightened us, 

Above all, a lasting and satisfactory solution requires human will and wisdom — at the individual, social, and political levels — to change our habits, comforts and current way of life in order to secure a future for ourselves and those who are yet to come. [para 456]

Thus, it is not the source of energy that is harmful; it is the lack of adherence to the substance and spirit of the regulatory framework governing such processes, requiring due diligence in order to achieve optimal outcomes, protecting the climate system, which causes the harm. However, with enhanced clarity in the nature and substance of these obligations through the AO and clear pathways for engaging state responsibility in the event of non-compliance, there must be an increased appetite to implement these obligations with a view to undertaking the green transition. There might not be plenty of one source of energy, but perhaps enough of all of them together to fulfil the obligations for the protection of the climate system.

Part II of this blog will address the effect of the advisory opinion on seabed mining.

Photo attribution: By Kseniya Lapteva on Unsplash