By Ayyoub (Hazhar) Jamali, postdoctoral researcher at the University of Zurich
In recent months, two international courts have recognised climate change-related obligations under two different legal regimes. In the case of Verein KlimaSeniorinnen Schweiz and Others v Switzerland, the European Court of Human Rights (ECtHR) has found that the right to life and the right to private and family life impose positive obligations on States to implement measures and regulations necessary to address climate change, insofar as it poses a risk to these rights. Similarly, the International Tribunal for the Law of the Sea (ITLOS) highlighted in its advisory opinion that States have a duty to take all necessary measures to prevent, reduce, and control anthropogenic greenhouse gas (GHG) emissions, guided by the best available science and international standards. In both cases, the reports by the Intergovernmental Panel on Climate Change (IPCC) played a significant role in shaping the courts’ decisions and findings. This underscores the critical influence of scientific research in guiding legal interpretations and reinforcing the necessity for international cooperation in combating climate change. The analysis below provides a short summary of the growing value of the IPCC reports and their application by the ECtHR and ITLOS in their recent findings and pronouncements.
The Value of IPCC Reports
The IPCC is a unique collaboration involving thousands of scientific experts from around the world, bringing together the most comprehensive and up-to-date understanding of climate science. This collaborative effort is unprecedented in the history of science, not only for its scale but also for the acceptance and reliance it has garnered from governments globally.
In fact, the IPCC’s research and updates of the state of knowledge on information relevant for the understanding of the risk of climate change have been crucial for the development of international climate law (Ghaleigh 2016). Beyond its role in shaping the collective response to climate change, the IPCC’s findings have also played a crucial role in the adjudication of climate litigation by courts. The IPCC has been described as the ‘world’s most authoritative assessment body on the science of climate change’ (Gloucester Resources Limited v Minister for Planning [2019] NSWLEC 7, paras. 431-435) and its reports have been crucial in both constructing the factual background of the case and underpinning the necessity of urgent and stringent climate mitigation policy (Urgenda Foundation v The State of the Netherlands, Supreme Court of the Netherlands, 2019; Commune de Grande-Synthe v France, Conseil d’État, 2021; Neubauer et al. v Germany, German Federal Constitutional Court, 2022).
Both the ECtHR and ITLOS, have extensively referenced various IPCC reports in support of their recent findings regarding the impacts of climate change on human rights and the marine environment respectively, as well as their reasoning underlying their conclusions. The IPCC reports indicated that increasing temperatures and heatwaves, exacerbated by climate change, lead to significant health risks and increased mortality. The ECtHR cited the IPCC’s conclusion that climate change results in more frequent and intense heatwaves, which disproportionately affect older adults, women, and those with chronic diseases (paras. 510, 511, 530). This evidence supported the applicants’ claims that the Swiss authorities’ failure to mitigate climate change posed a direct threat to their health and well-being, thus engaging positive obligations under Articles 2 and 8 of the European Convention on Human Rights.
In its AO, the Tribunal highlighted the IPCC’s findings on the necessity of limiting global warming to 1.5°C to mitigate severe impacts on marine ecosystems and human communities. It also underscored the need for rapid and substantial reductions in greenhouse gas emissions, as outlined in the IPCC reports, to meet international climate goals. In fact, the Tribunal’s reliance on authoritative scientific evidence provided by the IPCC underscores the importance of integrating robust climate science into legal deliberations. By utilising IPCC definitions and confidence levels in assessing climate change impacts, ITLOS was able to clarify key concepts (e.g., climate change, GHG emission, ocean acidification), prioritize issues, and reinforce its stance on the urgent need for States to address marine pollution and protect the marine environment (paras. 57-66, 157, 209-210, 241, 398).
Notably, the validity of the IPCC reports was not questioned by most participants in the AO proceeding or the Swiss government in the KlimaSeniorinenn case. The Swiss government even argued that its national emissions reduction targets relied on the IPCC’s assessment report (para 91). This broad acceptance of the IPCC’s findings highlights their critical role in shaping international climate-related legal obligations and policies.
Conclusion
The ECtHR and the ITLOS have both recognized climate change-related obligations under different legal regimes, emphasizing states’ responsibilities to mitigate climate risks. The ECtHR affirmed that climate change poses a direct threat to human rights, necessitating positive state actions, while ITLOS highlighted obligations to protect the marine environment from GHG emissions. The IPCC reports have played an important role in these judicial decisions and opinions, providing authoritative scientific evidence that underpins the necessity for urgent climate action. The recognition and reliance on IPCC reports by these courts reflect their authoritative status in climate science and their significant influence on international climate law and litigation.