Only 27 of 48 contiguous U.S. states show statistically significant rises in average temperature since 1950. Yet 41 states, 84 percent, are warming in specific segments of their temperature range that simple averages cannot capture.
Researchers María Dolores Gadea Rivas of the University of Zaragoza and Jesús Gonzalo of University Carlos III developed a framework to examine how warming unfolds locally across more than 26,000 daily temperature readings per state. Their analysis, published in PLOS Climate, reveals a pattern of regional inequality in how Americans experience climate change.
The West Coast now faces higher annual temperature extremes. Northern states feel warmer minimum temperatures instead. Some places register no average warming at all, yet still undergo shifts that strain crops, public health systems, and community risk perception.
These findings carry direct policy weight. Local conditions shape how warming is experienced, which means adaptation strategies must be tailored to specific areas rather than built on national averages. The researchers note that regional climate differences have received less detailed study than topics like public health or economic inequality.
The method could extend to other variables. The authors suggest precipitation patterns and rising sea levels as next applications, though their current work stops at temperature.
María Dolores Gadea Rivas and Jesús Gonzalo:
"Looking beyond average temperatures, we show that most U.S. states are warming in specific parts of the temperature distribution, even when average warming is not statistically significant. This reveals strong regional inequalities in how climate change is experienced across the United States."
The study used temperature data from 1950 to 2021 across the contiguous 48 states. The full analysis appears in PLOS Climate.
Reference: Gadea Rivas MD, Gonzalo J (2026) Regional heterogeneity and warming dominance in the United States. PLOS Climate 5(2): e0000808. https://doi.org/10.1371/journal.pclm.0000808