The ICJ Advisory Opinion on Climate Change (July 23, 2025) addresses key topics of international climate change law: The obligation of progression under the Paris Agreement, the right to a clean, healthy and sustainable environment and the issue of state responsibility for climate harm. This article points to the debate on these issues prior to the Advisory Opinion, summarizes the Court's approach and contextualizes its findings. While the Court did not reinvent international climate change law, the Opinion is a landmark case. Because the ICJ solved important conflicts of interpretation, the Opinion will serve as the new point of departure for future debates on climate change law.
Felix Lange (Mon,) studied this question.