“Paris at 50 degrees Celsius”: How can Paris adapt to heatwaves?

“Paris at 50 °C” is a mission that envisions an extreme heatwave scenario in which temperatures in Paris could reach 50 °C, aiming to prepare adaptive measures in advance. This commentary argues that the initiative provides valuable insights for other cities in planning and implementing climate change adaptation strategies. The “Paris at 50 °C” report outlines the background of the mission’s adoption by the Paris City Council and the adaptation measures currently underway. The mission represents an innovative urban climate adaptation model that combines an extreme heat scenario with bipartisan political support, citizen engagement, integration into urban planning, practical exercises, and immediate short-term actions. While many of these measures are individually feasible, financial and institutional constraints necessitate prioritization. Many adaptation actions also contribute to greenhouse gas mitigation, though further efforts are needed to stabilize the climate. “Paris at 50 °C” offers a foundational vision and practical direction for building sustainable and resilient cities.