April 21, 2017
Across most of the country, average temperatures have increased at a rate of about 0.13°F (0.07°C) per decade since 1910. That trend is in line with the broader trend of rising global temperatures fueled by the accumulation of heat-trapping greenhouse gases in the Earth’s atmosphere.
Of course warming isn’t uniform across the planet, and some regions are warming faster than others. And since the 1970s, warming across the U.S. has accelerated. On average, temperatures in the contiguous 48 states have been warming at a rate of 0.45°F (0.25°C) per decade since 1970.
The fastest-warming states over that period were New Mexico, Arizona and Delaware, which warmed at a rate of more than 0.6°F (0.3°C) per decade. The slowest-warming states were South Carolina, Georgia and Missouri, which warmed at a rate of 0.3°F (0.17°C) per decade.
This analysis draws on temperature data collected from the National Climatic Data Center’s Climate at a Glance database.