Climate Resilience Under Legal Scrutiny: France's Adaptation Plan Challenged in Groundbreaking Action
On April 7, 2025, a coalition of climate-impacted individuals and leading environmental NGOs—including Greenpeace and Notre Affaire à Tous—addressed a formal notice to the French government, challenging France's adaptation plan to climate change. This new action marks the latest chapter of the "case of the century" (l'Affaire du Siècle), in which the Administrative Court of Paris recognized in 2021 that the French government failed to meet the climate change mitigation goals set out by French regulations, in particular, greenhouse gas reduction targets. While the initial 2018 legal action was brought solely by environmental associations and focused on the State's actions taken to fight climate change, the current action targets the insufficiency of France's climate adaptation policies, specifically the third National Adaptation Plan to Climate Change issued on March 10, 2025 (Plan National d'Adaptation au Changement Climatique, or "PNACC 3ˮ).
In contrast to the earlier case—where the Paris Administrative Court, in its ruling of February 3, 2021, recognized ecological damage linked to climate change and held the French state responsible for failing to fully meet its emissions reduction commitments—the current claim is preventive and structural in nature. The claimants do not seek damages. Instead, they request judicial intervention to compel the French state to revise and strengthen PNACC 3, which they argue is both opaque and unfit to protect the population from already present climate impacts.
The formal notice relies on a comprehensive framework of national, European, and international legal sources, as well as recent advances in climate-related case law. It is based on the French Constitution and the Charter for the Environment—particularly Articles 1 and 3 establishing the state's duty to ensure a healthy environment and prevent environmental harm. The notice also draws on EU Regulation 2021/1119 (the European Climate Law) and references the landmark ruling of the European Court of Human Rights on April 9, 2024, in Verein Klimaseniorinnen Schweiz and others v. Switzerland. In this decision, the Court confirmed the justiciability of state obligations regarding climate adaptation under the European Convention on Human Rights, notably Articles 2 and 8, which address rights to life and respect for private and family life.
The PNACC 3 is challenged on multiple grounds. According to the claimants, the plan: (i) fails to carry out a comprehensive assessment of climate risks and vulnerabilities; (ii) lacks a coherent prioritization of adaptation measures; (iii) omits transformative or binding policies; (iv) does not allocate sufficient financial and human resources; (v) provides no effective tools for evaluation and monitoring; and (vi) neglects the specific vulnerabilities of certain populations and regions—including individuals with chronic illness or disability, residents of overseas territories, and marginalized communities.
If the government fails to provide a satisfactory response within the legally mandated two-month window following the issuance of the formal notice, the claimants intend to bring a legal action before the Conseil d'État to challenge the legal validity of PNACC 3 and argue that the government has breached its obligation to adapt public policy to the realities of climate change.
This potential litigation represents a significant evolution in climate legal strategy—shifting from reactive litigation based on harm to anticipatory litigation seeking to enforce preventive obligations. If successful, it could set a precedent by recognizing that climate adaptation is not merely a matter of policy discretion but a legally enforceable duty under constitutional, European, and human rights law. If a final decision in this case forces the state to integrate equity, accountability, and urgency into its adaptation efforts, this case could become a cornerstone in the development of climate adaptation jurisprudence.
