A new analysis by Climate Crisis 247, using data from the Yale Program on Climate Change Communication (YPCCC) and Climate Central, has identified U.S. counties where climate doubt is spreading most rapidly, even as they experience some of the fastest warming. The study focused on counties with populations over 50,000 where average summer temperatures rose by at least 1°F between 1970 and 2025. It measured the percentage point increase in residents who do not believe global warming is affecting U.S. weather from 2018 to 2025.