Environmental Science and Policy

A new peer‑reviewed study in PLOS Climate by researchers at Spain’s University of Charles III in Madrid and the University of Zaragoza finds that 41 of the 48 contiguous U.S. states show statistically detectable warming over roughly the past 70 years, covering about 84% of the lower‑48 land area. Using tens of thousands of daily temperature readings dating back to 1950, the authors argue that traditional reliance on state‑level average temperatures understates how widely climate change is affecting local conditions, and instead track the full range of daily highs and lows over time. They confirm average temperature increases in 27 states and identify significant additional warming signals in 14 more, particularly in the highest daily temperatures in Western states like California, Idaho, Nevada, Oregon, Washington and Wyoming and in central states such as Iowa, Minnesota, Montana, Nebraska and the Dakotas. The researchers say those "previously hidden" patterns mean more of the U.S. is experiencing measurable climate change than many earlier studies suggested, with implications for how federal and state governments design targeted mitigation and adaptation policies. Climate scientists and policy analysts are likely to use the results to refine state‑level risk assessments for heat waves, wildfires, agriculture and energy demand, and to push back against claims that warming is confined to a few regions.