Beyond the Threshold: The Urgency of Climate Change

On April 17, 2025, the Bulletin of the Atomic Scientists held a discussion exploring the risks of climate change and how to understand what planetary shifts are inevitable – and which are solvable – in this current era of scientific skepticism. Each year, new data strengthens our understanding of the planet's rising temperatures and growing environmental instability. With the increase in uncontrollable wildfires, stronger storms, and rising ocean levels, the question remains of whether we are too late to reverse – or significantly slow – our changing climate. There have been a few bright spots towards reaching targets set in the Paris Agreement, such as increases in sustainable energy generation and climate finance. Still, these advances have not yet slowed consistent record-breaking heat and a continued year-over-year rise of atmospheric carbon– leaving us to question whether there is a ‘tipping point’ – a threshold beyond which climate change is irreversible. Speakers include: Moderator: Alexandra Bell, president and CEO of the Bulletin of the Atomic Scientists. Inez Fung, Professor Emerita of Atmospheric Science in the Department of Earth and Planetary Science and the Department of Environmental Science, Policy and Management at the University of California, Berkeley. She is also a member of the Bulletin's Science and Security Board. Robert Kopp, Distinguished Professor in the Department of Earth & Planetary Sciences at Rutgers University. Femke Nijsse, Senior Lecturer in Innovation, Energy and Climate at the University of Exeter.