Armed conflicts from Kuwait to Vietnam continue to remind us that the environment can be deeply scarred by war, a reality that climate risks now magnify for many dependent communities. But while a certain amount of environmental damage may be considered inherent to war, the destruction must and does have limits. This post by ICRC legal advisers Vanessa Murphy and Helen Obregón, which launches a series on war, law and the environment co-hosted with the Conflict and Environment Observatory, provides an overview of the ICRC’s updated Guidelines on the Protection of the Natural Environment in Armed Conflict and sets out measures to accelerate better respect for international humanitarian law (IHL) rules protecting the natural environment.

It’s no coincidence: today’s armed conflicts largely unfold across the epicentres of our global environmental and climate crisis. Conservation Biology scholars have concluded that over 80% of all major armed conflicts between 1950 and 2000 took place directly in biodiversity hotspots, and according to UNEP, at least 40% of non-international armed conflicts between 1950-2009 were related to natural resources. At the same time, countries enduring conflict are on the front line of climate change: of the 25 countries most vulnerable to climate change and least ready to adapt, 14 are mired in conflict.

Against the backdrop of this grim collision of conflict, climate risks and environmental degradation, international law prescribes a range of action. Here we give a potted history of law, war and the environment, introduce the ICRC’s updated Guidelines on the Protection of the Natural Environment in Armed Conflict – as one contribution among many other necessary efforts to address the environment and climate crisis – and spotlight five key take-aways.

A green groundswell

International law’s protection of the environment in war has seen ebbs and flows over time. In the 1970s, the extensive use of herbicides during the Vietnam War drove the adoption of the 1976 ENMOD Convention and, right on its heels, Articles 35(3) and 55 in 1977 Additional Protocol I (AP I). Next, the burning and spilling of oil in Kuwait during the 1990–1991 Gulf War triggered a burst of action in the UN Security Council and General Assembly. Since then, a steady cadence of international legal developments have expressly addressed the environment in armed conflict, including the International Court of Justice’s 1996 Nuclear Weapons Advisory Opinion, the 1998 Rome Statute, the Eritrea-Ethiopia Claims Commission, UN Environmental Assembly resolutions, and the recent Treaty on the Prohibition of Nuclear Weapons.

Alongside these developments, UNEP post-conflict environmental assessments, civil society and others have documented how the environment has continued to suffer in war, even when there are no black smoke-filled skies from blazing oil preoccupying public attention. In addition, the climate crisis is increasingly defining how conflict-affected women, men, girls and boys experience their natural environment. Environmental impacts of war are now compounded by climate risks.

The international legal community has also recently warmed up. There is renewed momentum to ensure the environment is adequately protected in war. The Security Council has held two Arria-formula meetings on the topic, in 2018 and 2019. The 2020 and 2021 iterations of the UN Secretary General’s annual protection of civilian reports address the civilian suffering compounded by the environmental impact of conflict and climate change. Efforts to define an international crime of ecocide are underway and under blogosphere examination. And of critical significance, the UN International Law Commission’s draft principles on protection of the environment in relation to armed conflicts, adopted on first reading in 2019, are currently open for comment and the Commission will conclude its work in 2022. These draft principles complement the ICRC’s Guidelines because they have a broader temporal and material scope, drawing from various branches of international law. They also reflect that the IHL principles and rules on distinction, proportionality and precautions apply to the natural environment. Where there is overlap, the ICRC invites States and other actors to use the Guidelines as a resource during the ongoing consultation.

ICRC’s updated Guidelines: overview and five key takeaways

To step up our efforts to enhance respect for the relevant IHL rules, in 2020 the ICRC released its updated Guidelines on the Protection of the Natural Environment in Armed Conflict, setting out 32 IHL rules and recommendations. The first iteration of these was released in 1994, following a request from the UN General Assembly (para. 4). The updated version reflects developments in international law since then, in areas from weapons law to how conduct of hostilities rules apply to the natural environment.

Like their 1994 predecessor, the updated Guidelines focus on how IHL protects the natural environment; the interaction between IHL and other bodies of international law is not the focus but is briefly addressed in preliminary considerations (paras 25-41). A concise commentary accompanies each rule or recommendation to explain and clarify its source and applicability. The 2020 Guidelines were peer reviewed by external practitioners and academics, who provided input and constructive critique in their personal capacity.

The 2020 Guidelines are a reference tool for States, parties to armed conflicts, and other actors who may be called upon to promote, implement, apply and enforce IHL – a ‘one-stop shop’ of relevant IHL on the natural environment.

The Guidelines understand the ‘natural environment’ to constitute the natural world together with the system of inextricable interrelations between living organisms and their inanimate environment, in the widest sense possible. This is underpinned by the ICRC’s reading of the drafting history of AP I and the rules themselves (paras 15-16).

1. The use of methods or means of warfare that are intended, or may be expected, to cause widespread, long-term and severe damage to the natural environment is prohibited.

Rule 2 of the ICRC’s Guidelines – identified as a rule of customary IHL binding on all States in international armed conflicts and arguably in non-international armed conflicts (NIACs) – establishes an ‘absolute ceiling of permissible destruction’ prohibiting all widespread, long-term and severe damage to the natural environment regardless of considerations of military necessity or proportionality (para 49). For this reason, a high threshold – with three cumulative conditions – is required to trigger this prohibition. This has been considered by some as almost unattainably high (e.g. 2009 UNEP report) and the meaning of ‘widespread, long-term and severe’ has also been debated.

During the AP I negotiations, a number of States understood that the interpretation of the Protocol’s terms was not the same as the similar – but non-cumulative – ENMOD terms, but little clarity was provided on how these differ, and no official position was adopted (paras 52-53). What is certain is that in assessing the degree to which damage meets the threshold, current knowledge, including on the connectedness and interrelationships of different parts of the natural environment as well as on the effects of the harm caused, must be considered (para 54). Those employing methods or means of warfare must inform themselves of the potential detrimental effects of their planned actions and refrain from those intended or expected to cause the prohibited damage (para 55).

Other specific elements that should inform a contemporary understanding of these terms include UNEP’s recommendation to use the ENMOD precedents (pg. 91) as a starting point. The Guidelines’ commentary states:

  • Widespread’ should be understood as referring to damage extending to ‘several hundred square kilometers’ (para 60). This is based on several factors, including the meaning that should be given to the ‘area affected’ (para 57) and knowledge of the transregional nature of the effects of damage, which can go beyond the area directly affected by the use of a method or means of warfare (para 58).
  • Long-term’ would cover damage somewhere between the range of that not considered to be short term or temporary, such as artillery bombardment, and that with impacts in the range of years (possibly a scale of 10 to 30 years) (para 63). But additional precision is needed if this rule is to provide protection where damage falls outside of the clearly accepted higher limits and a number of touchstones should inform this. For instance, the duration of the indirect – not only direct – effects of the use of a given method or means of warfare, such as the ability of certain substances to persist in particular natural environments, should be considered (paras 64-66).
  • Severe’ should be understood to cover the disruption or damage to an ecosystem or harm to the health or survival of the population on a large scale, with normal damage caused by troop movements and artillery fire in conventional warfare generally falling outside the scope of this prohibition (para 72). In further determining what type of damage could be covered, effects ‘involving serious or significant disruption or harm to human life’ or ‘natural resources’ should be considered. At least to the extent that effects on ‘economic resources or other assets’ also result in disruption or damage to the ecosystem or harm to the health or survival of the population, these should also be considered.

Given that the AP I provisions aimed to cover damage or disruption to ecosystems on a large scale (para 68), ongoing efforts related to ‘ecocide’, defined in the domestic law of some States (para 79), could provide further elements to inform the meaning of the required threshold.

Beyond this rule, the Guidelines set out three other IHL rules that grant specific protection to the natural environment as such.

2. By virtue of its civilian character, the natural environment is protected by IHL rules governing the conduct of hostilities. This means that disproportionate environmental damage is prohibited.

 Legal discussions on the protection of the natural environment in IHL tend to be drawn towards the rule just discussed. More quotidian and relevant for contemporary conflicts are the protections provided to all parts of the natural environment as civilian objects by the IHL principles of distinction, proportionality, and precautions (Guidelines Rules 5-8).

Here, we spotlight the protection provided by the rule of proportionality in attack. Clarity around how it applies has long been a focus of the environmental community: in 2010, Bothe, Bruch, Diamond and Jensen identified the ‘lack of clarity about the practical issues of proportionality where environmental damage is collateral damage’ as one of the three challenges to protect the environment in war. The Guidelines’ commentary (paras 114-122) seeks to aid interpretation of the proportionality rule. Importantly, environmental data collection has advanced (e.g. here, here and here) and may contribute to assessing what damage is reasonably foreseeable in an attack.

When assessing proportionality, the basic rule requires that parties to conflict must take into account incidental civilian harm (including to the natural environment) that is reasonably foreseeable based on an assessment of information from all sources available to them at the relevant time (para 117).

The Guidelines offer a number of observations in this respect:

  • This obligation includes taking into account an attack’s indirect effects on the natural environment (para 117); the scope of the obligation and the related question as to reasonable foreseeability will depend on the facts of each case based on an assessment of information from all sources available at the relevant time, informed by past practices and empirical data (para 118).
  • As information regarding the long-term risks attendant to disruption of ecosystems increases, so too does the foreseeability of indirect effects, and assessments of excessiveness of incidental damage to the natural environment must take such information into account (para 118).
  • The weight given to various types of incidental civilian damage will vary. For example, damage to the natural environment in the middle of an uninhabited desert will carry much less weight than damage to a natural water reservoir used by villagers for drinking or irrigation (para 121).
  • An example of disproportionate incidental damage to the natural environment would be the burning of an entire forest to eliminate a single, small enemy camp of minor importance. To the extent that it constituted damage incidental to an attack, many experts considered that the pollution arising from the burning of oil fields and the deliberate spilling of millions of gallons of oil into the sea during the 1990–1991 Gulf War was excessive in relation to the military advantage that may have been anticipated (para 122).

3. Parties to a conflict should endeavour to conclude agreements providing additional protection to the natural environment in armed conflict, such as demarcating demilitarized zones.

Recommendation 17 of the Guidelines on the conclusion of agreements is based on multiple IHL rules (paras 203-213). In non-international armed conflicts, common Article 3 foresees that parties can conclude special agreements (para 203). This could be used as a basis to agree a myriad of additional protections for the natural environment, including the agreement of demilitarized zones. The conduct of hostilities may have particularly disastrous consequences when it occurs in areas of major environmental importance or fragility (e.g. areas containing unique ecosystems or endangered species) if they are not provided with effective and specific protection. While not without complexity, this kind of area-based demarcation offers commanders clarity needed to guide operational planning. The ILC’s draft principles similarly address designation of protected zones of major environmental importance.

IHL provides for the establishment of demilitarized zones (by agreement between parties) in both international and non-international armed conflicts (para 206). Article 60 of AP I provides a blueprint for the terms of an agreement on a demilitarized zone, but any such agreement can be tailored to each specific situation, as Article 60 recognizes, and could be established in NIAC pursuant to common Article 3. Demilitarized zones can be agreed in an ad hoc manner between States at any time and between State and non-State actors during a conflict (para 209); examples, including the Antarctic and the Åland Islands, are given in the ILC’s commentary on draft principle 4.

By establishing a demilitarized zone, parties agree to keep certain identified areas of particular ecological significance or fragility off-limits to military operations. Fighters and military equipment would be excluded from such zones, which could only be attacked if they contain a military objective.

Areas of major environmental importance that could be designated as demilitarized zones include groundwater aquifers, key biodiversity areas (which could be national parks or endangered species habitats), ecological connectivity zones, and areas important for coastal protection, carbon sequestration or disaster prevention. A range of existing resources could be used to help identify the zones concerned, including within the framework of international environmental law. Examples include sites of major environmental importance appearing on the World Heritage List, identified in the National Biodiversity Strategies and Action Plans of Parties to the Convention on Biological Diversity, or listed in IUCN’s conservation databases. States also have domestic legislation that could be referred to when identifying these areas (para 208).

The ICRC continues to be of the view that multilateral efforts to designate such zones more systematically would be worthwhile (para 210).

4. Non-State armed groups have a range of IHL obligations addressing the protection of the natural environment.

Unlike their 1994 predecessor, the 2020 Guidelines aim to serve as a reference for all parties to armed conflict, including non-State armed groups (para 11).

Of the 32 rules and recommendations in the Guidelines, more than half are also obligations for non-State armed groups parties to NIACs. To name a few, this includes: the rules of distinctions, passive and active precautions, and proportionality (Rules 5-9); the prohibitions regarding objects indispensable to the survival of the civilian population (Rule 10); the prohibition of the destruction of the natural environment not justified by imperative military necessity (Rule 13); and the prohibition of pillage (Rule 14). Perhaps unsurprising given the intertwining of civilian fates with environmental protection, some non-State armed groups have included IHL and other rules protecting the natural environment into their codes of conduct.

5. Key recommendations for States and parties to armed conflict

The Guidelines are intended to facilitate the adoption of concrete measures to reduce the environmental impact of armed conflict. To support this implementation, the ICRC proposes the following measures (para 14):

  • Disseminate IHL rules protecting the natural environment as reflected in the Guidelines and integrate them into armed forces’ doctrine, education, training, disciplinary systems and national policy and legal frameworks. National IHL committees or similar entities can work with national authorities in this regard.
  • Adopt and implement measures to increase understanding of the effects of war on the natural environment prior to and regularly during military operations, whenever feasible and operationally relevant, to minimize direct and indirect environmental impacts of these. For instance, States could carry out environmental impact assessments or map areas of particular environmental importance or fragility before the conduct of military operations.
  • Identify and designate areas of particular environmental importance or fragility as demilitarized zones. Designation could take place in peacetime or after fighting breaks out.
  • Exchange examples and good practices of measures to comply with relevant IHL, through activities such as conferences, military training and exercises, and regional forums. States could also, for example, carry out or share scientific assessments of the proportionality of damage caused to the natural environment by certain types of weapons or offer technical advice on measures to better protect areas of particular environmental importance or fragility.

Working together towards a green future

The ICRC’s Guidelines and the IHL therein do not address all environmental impacts of conflict, but IHL does place limits on permissible environmental damage for warring parties, and as such is one contribution among many other critical efforts being led by States, National Societies and actors like UNEP, the ILC, PAX and CEOBS to address the existential threat our planet faces. We all have a part to play.

In the coming months, this blog series will feature contributions from a diverse range of experts to raise awareness of international law protecting the environment in war and spotlight contemporary initiatives seeking to address related legal, military and other challenges. We invite those interested to contribute.

The current sense of momentum to ensure adequate environmental protection in wartime is heartening. It is also fueled by cognizance that we are in a moment of great peril: when the environment dies, we do too. Parties to armed conflict are fighting without a planet B.

See also