Author Nicole Ann Ponce © private

Origins of the call for an ICJ Advisory Opinion on climate change

The climate crisis knows no boundaries. Its consequences are far-reaching and disproportionately affect people and communities already marginalized, including small island communities, Indigenous Peoples, women and girls, and those living in conflict-affected or climate-vulnerable regions. It exposes broader injustices and exacerbates existing vulnerabilities, contributing to the erosion of fundamental human rights. In the Pacific, island nations are facing rising sea levels that threaten to consume entire nations, displace communities, and erase centuries of traditions and cultural heritage.

It is for this reason that, in 2019, the initiative to request an Advisory Opinion (AO) on climate change from the International Court of Justice (ICJ) began. A group of students from the University of the South Pacific, later known as Pacific Islands Students Fighting Climate Change (PISFCC), came together to launch a campaign. This call from the Pacific resonated with young people around the world. Recognizing the need for broader global support, World’s Youth for Climate Justice (WYCJ) was established. Young people from Asia, Latin America, Africa, Europe, and the Caribbean organized across regions to rally support from their governments for the request for an ICJ Advisory Opinion.

WYCJ’s role in securing the ICJ Climate Ruling

From the outset, climate justice, human rights, and intergenerational equity have been at the forefront of the campaign and its advocacy. WYCJ played a key role in establishing the nexus between climate change and human rights, using human rights as both a legal hook and a strong entry point for advancing claims and shaping legal arguments. Intergenerational equity was utilized not only as a narrative arc but as a concrete legal demand. This is also captured in the legal questions of the United Nations General Assembly (UNGA) resolution requesting the Advisory Opinion, which explicitly addresses obligations toward present and future generations.

WYCJ helped ensure that the voices of those bearing the brunt of the climate crisis were not excluded from this critical legal process. Youth representatives from Sri Lanka, Nepal, the Philippines, Singapore, Mexico, Costa Rica, Kenya, The Bahamas, Germany, and the Netherlands directly engaged with their governments in preparing their States’ submissions to the ICJ, demonstrating their capacity to shape international law in ways that centre equity, human rights, and climate justice. Young people from all over the world energized and sustained a global campaign and alliance that ultimately led to what prominent figures have called the “climate case of the century.” 

The legal questions put to the court

The significance of the ICJ Advisory Opinion (AO) on climate change is already reflected in the legal questions put to the ICJ:

  1. What are the obligations of States under international law to protect the climate system and the environment from anthropogenic greenhouse gas emissions, for present and future generations?
  2. What are the legal consequences for States whose actions or omissions cause significant harm, particularly to vulnerable island States and peoples, both now and in the future?

These questions have long been contested in climate negotiations. Some States have argued that climate treaties should be treated as the primary, or lex specialis, framework for addressing climate change, thereby narrowing the role of other applicable laws of international law, including human rights law and customary international law. Responsibility has also been a point of contention, with arguments that climate harm results from cumulative emissions, making it difficult to establish attribution and causation in relation to particular States.

Key findings of the ICJ Ruling

The ICJ Advisory Opinion represents a legal breakthrough in that it brings together human rights law, environmental law, State responsibility, and duties of international cooperation into a more coherent legal framework. Its dismisses the argument that climate treaties establish a lex specialis, affirms that other bodies of law apply alongside climate treaties and clarifies their interaction.

Key clarifications from the Court:

  • 1.5°C is the primary temperature goal under the Paris Agreement. It is not merely aspirational but carries legal significance in guiding State conduct.
  • States are obligated to prevent harm to the climate, including the regulation of private actors. Failure to curb the production and use of fossil fuels, the main drivers of the climate crisis, may constitute a breach of international law.
  • States must take ambitious action to protect the environment to ensure the effective enjoyment of human rights. The Court reaffirmed that the environment “is the foundation for human life, upon which the health and well-being of both present and future generations depend.”
  • The customary international law duty of care to prevent transboundary environmental harm applies fully to the climate system. This obligation applies even where it is difficult to attribute a precise level of responsibility to an individual State. States with greater capabilities must exercise a higher standard of care.  
  • Loss of territory due to sea-level rise does not imply loss of statehood.
  • States do not have unfettered discretion in determining the content of their Nationally Determined Contributions (NDCs). Each NDC must reflect the highest possible ambition, make an adequate contribution to the collective 1.5°C goal, and become progressively more ambitious every five years.

UNGA Resolution: a political momentum to operationalize the Climate Ruling

The ICJ Advisory Opinion was a watershed moment, providing long-needed legal clarity. But as Vishal Prasad, Campaign Director of the PISFCC, powerfully put it: “Legal clarity alone does not protect a single village from rising seas.”  The challenge before us is no longer interpretation, but implementation.  Therefore, Vanuatu and a core group of other States have introduced a resolution to be voted on by UNGA to operationalize the ICJ decision. Informal negotiations on the resolutions’ text are currently ongoing, the vote is expected in late April or early May 2026. The General Assembly can ensure that the Court’s legal findings are not relegated to a optional guidance but influence real-world decisions, policies, and actions.

An UNGA resolution could play several key roles:
  • First, it would be a strong signal that the international community recognizes the legal guidance provided by the Court and considers it relevant to ongoing climate governance — not merely symbolic. It would help integrate the ICJ Opinion into existing climate processes, including UNFCCC negotiations, national climate policies, international financial discussions, and human rights mechanisms.
  • Second, a strong resolution would allow vulnerable States and civil society to use the Opinion in negotiations, domestic policymaking, litigation, and leverage it in the work they are already doing on the frontlines.
  • Third, it would create an opportunity for those most affected by the climate crisis to help shape the path forward. This process is not only about diplomacy between States but about climate justice; it is also about whether the experiences of frontline communities are reflected in global action.

Call to action

We are now at a moment of opportunity. Reach out to Austrian ministries and diplomats and ask clear questions: What is Austria’s position? Has it co-sponsored the resolution? How will it vote? Use letters, meetings, public statements, and coalitions to build pressure and momentum. At the same time, help translate the Advisory Opinion into clear, actionable policy pathways that governments can realistically adopt.

But engagement alone is not enough — we must organize for ambition. This resolution must go beyond symbolic. It should reflect the legal clarity provided by the Court and send a strong signal that States are ready to act on their obligations. Civil society, youth movements, and academic institutions all have a role in raising the level of ambition.

Austria has long positioned itself as a champion regarding climate protection, human rights and multilateralism — this is a concrete opportunity to translate that commitment into action. To Austrian decision-makers: Co-sponsor and vote yes to the UNGA resolution!

References

About the author

Nicole Ann Ponce is an environmental and human rights lawyer–advocate from the Philippines with a strong interest in the intersection of law, science, and policy. She co-founded World’s Youth for Climate Justice (WYCJ) and serves as its Advocacy Lead. WYCJ is one of the youth-led organisations, together with PISFCC, that was instrumental in securing the historic 2025 International Court of Justice Advisory Opinion on Climate Change and Human Rights. She also works as a research project contracts officer at the Centre national de la recherche scientifique (CNRS) in Paris and is a Fellow of the Asian Research Institute of Environmental Law (ARIEL).

She oversees the Advisory Opinion implementation workstream, coordinating efforts to translate the legal obligations clarified by the ICJ, ITLOS, and IACtHR into ambitious national, regional, and international action. Her work includes leading international advocacy in multilateral negotiations, developing regional implementation plans, and engaging governments to integrate these obligations into legislation and policy. In parallel, she works on advancing the adoption of these Advisory Opinions within the UN system, including by Special Procedures and human rights treaty bodies.

In its ‘Global Voices’ section, Global Responsibility invites international experts to comment on current issues, challenges and opportunities in development and humanitarian policy. To ensure democratic and sustainable debates, it is essential that diverse and critical perspectives are taken into account. This commentary has been published as part of an International Partnerships Austria project, funded by the Austrian Development Agency (ADA). ADA accepts no responsibility for the content produced by partner organizations. Statements, opinions, and information contained therein are the sole responsibility of the respective authors and do not necessarily reflect the position or views of ADA.

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