Extreme heat events are growing more frequent, widespread and underestimated
A record-breaking heat wave sweeping across the U.S. and Europe is being driven by fossil fuel pollution and made more dangerous by nighttime temperatures that offer little relief.
Andrew Freedman reports for CNN.
In short:
- Scientists say every heat wave today is hotter than it would have been without climate change, and computer models are underestimating the trend's severity.
- This U.S. heat wave, affecting about 150 million people, is the first of the season and is already threatening all-time temperature records, including record warm nights.
- Extreme heat is now more common on multiple continents at the same time, with humidity, longer duration, and earlier seasonal onset compounding the health and infrastructure toll.
Key quote:
“Every heatwave that is occurring today is hotter than it would have been without human-induced climate change.”
— Fredi Otto, climate scientist and lead of the World Weather Attribution project
Why this matters:
Heat waves are no longer isolated or predictable — they’re intensifying, spreading, and striking earlier in the season, catching people and infrastructure unprepared. As global temperatures rise, these events are becoming more humid and longer-lasting, which increases their threat to human health. Hotter nights deny the body time to recover, particularly for the elderly, infants, and those with chronic conditions. Urban areas bear the brunt due to heat-trapping buildings and pavement.
The implications stretch beyond health: Heat stresses power grids, warps roads and railways, and damages crops, threatening food security. While storms and floods draw dramatic headlines, heat quietly kills more Americans each year than any other weather hazard. And climate models may be underplaying what’s still to come.
Related: How youth can battle extreme heat in their communities
