The author outside the Peace Palace in The Hague
Weather Report from the Eye
This past July, I happened to be at the Peace Palace on the day the World Court delivered its advisory opinion on the obligations of states in respect of climate change (“the Climate Advisory Opinion”).
Highly anticipated by the myriad representatives of states and international organisations gathered from around the world who had participated in the related proceedings, there seemed a special energy surrounding the occasion.
The judgment did not disappoint.
In fact, the Climate Advisory Opinion was one of two advisory opinions delivered by the World Court this year.
The second was delivered in October: on the obligations of Israel in relation to the presence and activities of the United Nations, other international organisations, and third states in and in relation to the Occupied Palestinian Territory (“the Occupation Advisory Opinion”).
Two advisory opinions. Two distinct subjects.
With this short article, I aim to accomplish two things:
- To briefly recount the journeys which led to the advisory opinions; and
- To highlight key points of international law which have arisen from them.
In the undertaking, I hope to equip you not only with a high-level understanding of the jurisprudence emerged from the World Court this year, but also with an improved picture of international law’s grammar and evolving ambit.
The Climate Advisory Opinion
From Island Voices to the Peace Palace
The climate advisory opinion did not necessarily emerge from a sudden question dropped into the World Court’s lap. It was the culmination of something like a global groundswell. A steady gathering of voices, most prominently from the Pacific, asking for clarity on what international law actually requires from States in the face of escalating climate harm.
Vanuatu took the lead, supported by a coalition of Small Island Developing States, which brought a particular moral clarity to the request. For them, climate change was not merely a diffuse policy challenge. In light of disproportionate projected impacts, it was an existential matter. Their appeal to the General Assembly was simple and direct: it was time for the international community to understand the legal obligations attached to climate risk.
By the time the proceedings began, the volume of engagement was extraordinary. More than ninety (90) states and organisations filed written statements. The ensuing oral hearings resembled a kind of global legal forum. Representatives seemed to treat the World Court less as an aloof judicial body and more as an anchor, a place from which the law might finally be consolidated and stabilised in a field arguably adrift between science and politics for decades.
On the morning the judgment was handed down at the Peace Palace, that sense of anticipation was clear in the air. Delegates, lawyers, and observers alike seemed to recognise they were witnessing the World Court speak on an issue that touched every aspect of the international system.
The Court seemed well-aware of the moment’s significance.
The Architecture of the Court’s Reasoning
The Climate Advisory Opinion opened with a measured but unmistakably serious framing: climate change poses “an urgent and existential threat”,[1] with consequences that are “are severe and far-reaching,” affecting “both natural ecosystems and human populations.”[2]
From that foundation, the Court moved in a way that was both restrained and quietly ambitious:
(a) The classic no-harm rule, brought into the 21st century
The Court held that activities causing significant transboundary harm fall squarely within the no-harm rule, and that greenhouse gas emissions (“GHG’s”) qualify. Humans causing the increase in concentration of GHGs in the atmosphere, it expressed, was “scientifically established.”[3]
Accordingly, customary international law was aligned with contemporary climate science.[4]
(b) Obligations of conduct and result
States were required to adopt and implement mitigation and adaptation measures with due diligence.[5] That comprised the conduct part.
On results, the Court did not impose new targets but acknowledged that temperature goals set in the existing climate treaty framework pose relevant benchmarks for assessing whether states meet their existing legal obligations.[6]
(c) Historical responsibility as a legal factor
Matter-of-factly, the Court confirmed that the scale of a state’s contribution to cumulative emissions and its capacity to respond are relevant circumstances, stating in no ambiguous terms “[i]t is scientifically possible to determine each State’s total contribution to global emissions, taking into account both historical and current emissions.”[7] The Climate Advisory Opinion marked the closest jurisprudence has come to articulating differentiated responsibilities in customary form.
(d) Time runs forward — intergenerational equity recognised
The Court observed that climate impacts fall on “present and future generations,” indicating that equitable considerations operate not just horizontally, between states, but vertically, through time.[8]
(e) Human rights obligations reinforce environmental ones
The Court tied climate obligations to recognised rights to life, health, food, water, and an adequate standard of living, doctrinal connections likely to influence human rights litigation for years to come.[9]
Taken in whole, the Climate Advisory Opinion reads like the Court gently but firmly tuning the foundational instruments of international law, co-ordinating principles of environmental law, human rights law, and state responsibility to develop their collective operational coherence in a rapidly changing world.
The Occupation Advisory Opinion
Humanitarian Strain and Institutional Friction
The second advisory opinion of the year emerged from a very different context. It was one not characterised by the gradual building of scientific consensus, but by a rapidly deteriorating humanitarian situation.
The General Assembly’s request, adopted in December 2024, was unusually specific. It referred to:
- Growing restrictions on UN operations;
- Obstruction of UN personnel;
- Insecurity of humanitarian facilities; and
- The wider impact on civilian access to essential services.[10]
Israel did not participate in the advisory proceedings, but a wide range of states and organisations did. Their submissions circled the same central question: in an occupied territory, what does international law require of the occupying power vis-à-vis the United Nations and humanitarian bodies?
By the time the Court delivered its opinion in October, the situation in Gaza had worsened considerably. Accordingly, the opinion represented both a legal exposition and a response issued in real time to a live and urgent crisis…
What the Court Clarified
(a) Jurisdiction: political tension does not deprive the Court of its role
The Court reaffirmed that it may answer legal questions even when they arise in intensely political circumstances, noting the central question posed through the UN Resolution was “a legal question.”[11]
(b) Israel’s status as an occupying power triggers the full framework of occupation law
The Court indicated that the Fourth Geneva Convention applies. In particular, Article 59 requires an occupying power to “agree to and facilitate” relief schemes organised by impartial humanitarian bodies.[12]
The Court repeatedly stressed that aid must reach civilians swiftly, regularly and without interference.[13]
(c) United Nations Relief and Works Agency for Palestine Refugees in the Near East’s (“UNRWA”) neutrality stands
After reviewing the material before it, the Court found nothing sufficient to negate UNRWA’s character as an impartial humanitarian organisation. Accordingly, the Court found Israel under an obligation to agree to and facilitate its work.[14]
(d) Certain prohibitions admit no ambiguity
The opinion restated, in language sharper than usual, that, inter alia:
- Starvation of civilians is prohibited;
- Forcible transfer is prohibited;
- Medical and relief personnel must not be obstructed; and
- Access for the International Committee of the Red Cross must be guaranteed.[15]
(e) Charter obligations cannot be overridden by domestic law
The Court expressed that Israel’s obligations under the UN Charter, including respect for the immunities of UN officials, supersede domestic measures to the contrary. Relevantly, the Court also recalled the “permanent responsibility” of the UN for the question of Palestine.[16]
(f) Humanitarian access and self-determination are linked
The Court observed that the ability of UN bodies to operate freely is tied to the Palestinian people’s right to self-determination: a reminder that humanitarian law and self-determination are considered to intersect, even when not explicitly stated.[17]
Together, the conclusions seem to assert an overarching stance that occupation law’s protections are not to be suspended by political disagreement or domestic legislation. They are supposed to be structural.
Between Two Storms
Looking at the two opinions together, what stands out is how differently the Court responded to two different kinds of tempest.
The Climate Advisory Opinion gave an impression of the Court looking far ahead, taking scattered threads of environmental law, human rights obligations, and state responsibility, and weaving them into a coherent jurisprudential structure for the Anthropocene.
The Occupation Advisory Opinion, by contrast, felt like the Court grounding the jurisprudence, reaffirming the limits international law has long placed on occupying powers, especially where humanitarian access is concerned.
One opinion was about diffuse, planetary-scale risk.The other was about immediate, tangible human survival.
I’d hazard to suggest they share a common theme: a world moving through crises exceeding the capacity of politics alone. Amidst the tumultuousness, international law (however ready) is being asked to fill the gaps.
Thoughts in Closing
For practitioners in municipal and international law fields alike, advisory opinions from the World Court can sometimes seem remote: intellectually interesting, but not always immediately relevant. Occasionally, however, the Court produces opinions that feel like signposts: juristic markers mapping the shifting terrain of civilisational self-perception and governance.
This year, I believe we received two such markers:
- The Climate Advisory Opinion pointing toward the legal responsibilities of States as planetary custodians across generations; and
- The Occupation Advisory Opinion pointing toward the normative inviolability of humanitarian action preserving lives in moments of acute crisis.
Together, they sketch a portrait of international law in a moment of escalating global strain: stretched, evolving, yet still seemingly capable of clarity.
Between tempests, judgment continues to steady.
[1] The Climate Advisory Opinion, para 73.
[2] Ibid.
[3] Ibid, para 72.
[4] Ibid, see generally paras. 134-136.
[5] Ibid, para 135.
[6] Ibid, paras. 224-226.
[7] Ibid, para 429.
[8] Ibid, para 157.
[9] Ibid, see generally paras. 372-377.
[10] See United Nations Request for an advisory opinion of the International Court of Justice on the obligations of Israel in relation to the presence and activities of the United Nations, other international organizations and third States, GA Res 79/232, UN Doc A/RES/79/232 (adopted 19 December 2024).
[11] The Occupation Advisory Opinion, para 21.
[12] Ibid, paras. 93-95.
[13] Ibid, see for examples paras. 188-215.
[14] Ibid, paras. 110-124.
[15] Ibid, see generally paras. 128-145.
[16] Ibid, paras. 163-179.
[17] Ibid, para 221.
