Global Heat Waves Reach Unprecedented Levels

By Alicia Green • Published June 5, 2025 • Updated June 6, 2025

This summer’s heat waves are now being described as a “new normal” by climate scientists, as cities from Los Angeles to New Delhi record temperatures more than 4 °F above historical averages.

Residents in Europe and Asia endured prolonged heat indices above 100 °F, causing energy grids to strain and prompting emergency declarations by government agencies.

We’re facing a future where hundred-degree days won’t just be summer peaks — they’ll be the norm.

New satellite data show that Earth’s surface temperature thresholds have been broken multiple times in May, a month that traditionally registers lower peaks.

Cities without robust cooling infrastructure found themselves in dire situations, particularly older populations and low-income neighborhoods lacking green space.

“It’s no longer enough to adapt,” said Dr. Lina Sorensen, a climatologist at the University of Copenhagen. “We need to re-think urban design and human habitat resilience.”

About the author:
Alicia Green is an environmental correspondent covering climate change and extreme weather events from multiple continents.