Almost no one had heard of global warming when the U.S. commemorated its first Earth Day 44 years ago. Now most Americans know about anthropogenic climate change—whether or not they accept the science is another story. But the temperature records for our 50 states say it all: we’ve observed a gradually warmer Earth Day on average since that first celebration, as Climate Central reports in the interactive below:
In Climate Central's words: Average temperatures across most of the continental U.S. have been rising gradually for more than a century, at a rate of about 0.127F per decade between 1910-2012. That trend parallels an overall increase in average global temperatures, which is largely the result of human greenhouse gas emissions. While global warming isn’t uniform, and some regions are warming faster than others, since the 1970s, warming across the U.S. has accelerated, previously shown in our report The Heat is On. Since then, every state’s annual average temperature has risen accordingly. On average, temperatures in the contiguous 48 states have been warming at a rate of 0.48F per decade since 1970, nearly twice the global average.
Delaware and Wisconsin are tied as the fastest-warming states since 1970, warming at a rate of 0.67F per decade. Average annual temperatures in the two states are about 3F warmer than they were 44 years ago. Vermont, New Jersey, and Michigan are warming nearly as fast, and all are warming about twice as fast as the global average. The slowest-warming states are Washington, Georgia, Florida, and Oregon – warming just more than 0.3F per decade since 1970 — and are on pace with average global temperatures.
For detailed information on individual states, click on any state in the interactive graphic above.
On a regional scale, the fastest-warming areas are the Northeast, Midwest and Southwest, while the Pacific Northwest and Southeast are warming more slowly. Of the lower 48 states, 26 have warmed more than 2F since 1970, and 16 have warmed more than 2.5F.
The data in this analysis came from the National Climatic Data Center’s Climate at a Glance database.