Climate Damage from Armed Conflict and Emerging Erga Omnes Environmental Obligations

Armed conflicts generate consequences that extend far beyond immediate humanitarian devastation and geopolitical instability. Warfare is also increasingly recognized as a significant driver of environmental degradation and climate change. Recent studies indicate that military operations, destruction of infrastructure, landscape fires, and post-conflict reconstruction generate substantial greenhouse gas emissions and long-term ecological damage.

Recent conflicts illustrate the scale of these impacts. The war in Ukraine, for example, has generated approximately 230 million tonnes of CO₂ equivalent emissions between February 2022 and early 2025, resulting from military operations, landscape fires, destruction of energy infrastructure, and reconstruction activities.

Studies indicate that climate change is increasingly recognized as a multiplier of existing tensions, particularly where environmental stress interacts with political instability and resource competition. In the Middle East and North Africa ("MENA") region, this “threat multiplier” effect is further intensified. While the region has long been characterized by geopolitical tensions and armed conflicts, it is also among the most climate-vulnerable regions globally. Scientific projections indicate that the region is warming at nearly twice the global average, with temperatures expected to increase by up to 4°C by 2050 under high-emission scenarios. Rising temperatures, declining precipitation, and increasing drought frequency pose serious risks to water security, agriculture, and human livelihoods. The region is already widely recognized as the most water-stressed in the world, with several states relying on limited groundwater resources and transboundary river systems such as the Euphrates –Tigris basin. In this context, environmental degradation resulting from armed conflict in the MENA region may generate not only risks to regional stability but also complex challenges for global environmental sustainability.

This article argues that the environmental consequences of armed conflict increasingly raise collective responsibility grounded in the protection of global environmental interests beyond traditional bilateral responsibility.

1. Existing Legal Frameworks

The environmental consequences of armed conflict raise important questions regarding the adequacy of existing international legal frameworks governing environmental and climate protection during hostilities.

International humanitarian law contains several provisions aimed at protecting the natural environment during armed conflict. In particular, Articles 35(3) and 55 of Additional Protocol I to the Geneva Conventions prohibit methods or means of warfare that are intended or expected to cause widespread, long-term, and severe damage to the natural environment. These provisions are complemented by the Convention on the Prohibition of Military or Any Other Hostile Use of Environmental Modification Techniques.

More recently, the International Law Commission’s Draft Principles on Protection of the Environment in Relation to Armed Conflicts (2022) have sought to clarify environmental obligations applicable before, during, and after armed conflict.

In terms of the broader international climate regime, the United Nations Framework Convention on Climate Change and the Paris Agreement establish a global framework for addressing climate change, recognising the protection of the climate system as a common concern of humankind. While these instruments do not specifically regulate armed conflict, they reinforce the obligation of states to limit greenhouse gas emissions and may inform the interpretation of state obligations through principles of systemic integration under international law.

2. Evolution of General International Environmental Law

Environmental protection during armed conflict must also be understood within the broader framework of general international environmental law.

One of the foundational principles in this regard is the no-harm principle, which obliges states to ensure that activities within their jurisdiction or control do not cause significant environmental damage to other states or areas beyond national jurisdiction. This principle was first articulated in the Trail Smelter Arbitration and later reaffirmed by the International Court of Justice ("ICJ") in Pulp Mills on the River Uruguay.

The ICJ has also addressed environmental damage arising directly from armed conflict. In Armed Activities on the Territory of the Congo, the Court held Uganda internationally responsible for environmental damage and unlawful exploitation of natural resources resulting from its military activities in the territory of the Democratic Republic of the Congo. Similarly, the Eritrea–Ethiopia Claims Commission recognized that environmental damage resulting from military operations may give rise to international responsibility and compensation claims.

In its Advisory Opinion on the Legality of the Threat or Use of Nuclear Weapons, the ICJ has emphasized the importance of environmental protection during armed conflict by stressing that the environment represents “the living space, the quality of life and the very health of human beings, including generations unborn”. This statement reflects an emerging understanding of environmental protection as a fundamental value underpinning international law.

These developments may suggest a potential evolution toward recognizing certain environmental obligations—particularly those relating to the protection of the global climate system—as obligations of an erga omnes character. The ICJ first articulated this doctrine in Barcelona Traction and reaffirmed it in the Application of the Convention on the Prevention and Punishment of the Crime of Genocide, recognizing that certain obligations—such as the prohibition of genocide, basic human rights protections, and the prohibition of racial discrimination—are owed to the international community as a whole. Erga omnes obligations allow states to invoke responsibility for breaches affecting the collective interests of the international community.

Environmental protection may also be examined through the lens of peremptory norms (jus cogens). Under Article 53 of the Vienna Convention on the Law of Treaties, jus cogens norms are norms of general international law accepted and recognized by the international community of states as a whole, from which no derogation is permitted.

Although no international court has yet explicitly recognized environmental protection norms as jus cogens, an evolving body of scholarship suggests that certain environmental principles may eventually attain such status. These include the no-harm principle, the right to a healthy environment, and the prohibition of widespread environmental destruction during armed conflict. These developments demonstrate the growing recognition that environmental harm during armed conflict may engage collective international legal responsibility. 

Recent international jurisprudence has further strengthened the legal foundations of climate responsibility. In 2024, the International Tribunal for the Law of the Sea ("ITLOS") issued an Advisory Opinion recognizing greenhouse gas emissions as a form of marine pollution under the United Nations Convention on the Law of the Sea.

The ICJ also issued its advisory opinion on the Obligations of States in respect of Climate Change, affirming that states have binding obligations under international law to protect the climate system and to take measures consistent with limiting global warming to 1.5 °C in accordance with the Paris Agreement. Failure to comply with these obligations may constitute an internationally wrongful act, giving rise to duties of cessation, assurances and guarantees of non-repetition, and full reparation under the Articles on Responsibility of States for Internationally Wrongful Acts (for previous coverage, see here).

As a result, environmental harm arising from armed conflict—particularly where it contributes to climate change—cannot easily be confined within a bilateral framework of responsibility. Instead, such harm increasingly implicates shared environmental interests of the international community, thereby providing a normative basis for the gradual extension of responsibility toward forms of collective accountability.

3. Climate Litigation and Criminal Law

Parallel avenues are also possible in national courts and human rights mechanisms, and, in limited cases, in international criminal law. Climate litigation has emerged as an important mechanism for enforcing environmental obligations. As reported by the UN Environment Programme, by 2023, more than 2,500 climate-related cases had been filed worldwide, reflecting the rapid expansion of climate litigation. One of the most influential decisions in this field is Urgenda Foundation v Netherlands, in which the Dutch Supreme Court held that the state had a legal duty under the European Convention on Human Rights to protect its citizens from the dangers of climate change. Although no climate litigation cases have yet arisen directly from armed conflict, such claims may well emerge as a viable forum in the near future, particularly where environmental harm resulting from military activities can be linked to broader climate impacts.

Recent debates have also focused on whether large-scale environmental destruction should be recognized as an international crime. The Rome Statute of the International Criminal Court criminalizes attacks causing widespread, long-term, and severe environmental damage under Article 8(2)(b)(iv).

However, the high threshold for liability has limited its practical application. Consequently, increasing attention has turned to the emerging concept of ecocide. In 2021, an Independent Expert Panel proposed defining ecocide as unlawful or reckless acts committed with knowledge that there is a substantial likelihood of severe and either widespread or long-term environmental damage. While not currently recognized under international criminal law, the proposed concept of ecocide could, if adopted, significantly strengthen legal accountability for large-scale environmental destruction, including damage caused during armed conflict.

4. Conclusion

In the absence of a unified enforcement framework, environmental harm arising from armed conflict can no longer be understood solely within the confines of traditional bilateral responsibility between directly affected states. Rather, existing legal developments indicate a gradual expansion of accountability across multiple fora, including international courts and tribunals, national jurisdictions, and human rights mechanisms. Taken together, these developments show an emerging movement toward forms of collective responsibility, particularly where environmental harm affects shared ecosystems or the global climate system.