Data: Climate Central/RCC-Acis.org/ NCEI; Note: Average temperatures rounded up to nearest tenth. No data available for Hawaii; Map: Jacque Schrag/Axios
Since the first Earth Day on April 22, 1970, the U.S. national average temperature has climbed by 2.6°F, and the states have warmed — many significantly.
Why it matters: Earth Day is supposed to be a symbol of the environmental movement, originally born out of air and water pollution. But now it's a reminder of human-caused climate change — which is leading to more frequent and severe heat waves and wildfires, stronger hurricanes and heavier precipitation events.
