Figure 5a: Synthesised changes in the likelihood of exceeding a 26°C WBGT threshold during the tournament period across selected World Cup host stadiums in the 2026 climate relative to a 0.7°C cooler climate representing 1994, the last time FIFA hosted a World Cup in the United States Observation-based dataset (ERA-Land) is shown in blue, climate model results in red, and the synthesised estimates in magenta. Coloured bars indicate a 95% confidence interval obtained by bootstrapping; where no bar is shown, the uncertainty was found to be infinite.