June's European Heatwave Was 2°C Hotter Than 2003 Because of Climate Change

World Weather Attribution determined that June 2026's record European heatwave would have been virtually impossible without human-caused climate change. Its modeling shows that an equivalent heatwave in June 2003—which killed tens of thousands—would have been roughly 2°C cooler. Since 2003 anchored European heat mortality studies for two decades, this 2°C spike fundamentally reshapes how public health officials across the continent plan for extreme heat.