Happy, Hot Earth Day! [Interactive]

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.

Join Our Community of Science Lovers!

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


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 0.127°F 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 0.48°F per decade since 1970, nearly twice the global average.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Delaware and Wisconsin are tied as the fastest-warming states since 1970, warming at a rate of 0.67°F per decade. Average annual temperatures in the two states are about 3°F 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 0.3°F 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 2°F since 1970, and 16 have warmed more than 2.5°F.

The data in this analysis came from the National Climatic Data Center’s Climate at a Glance database.

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe