Climate change has made heat waves last longer, study finds

LOS ANGELES - A recent study reveals that climate change is causing massive heat waves to move at a slower pace across the planet, resulting in prolonged exposure to higher temperatures over larger regions, intensifying the heat's impact on populations.

The findings, detailed in a comprehensive report published on Friday within the esteemed scientific publication Science Advances, shed light on a concerning trend: global heat waves are exhibiting a significant slowdown, moving at a reduced pace by approximately 20%. Moreover, this phenomenon is occurring with alarming frequency, marking a staggering increase of 67% in their incidence.

This indicates that the slowing spread of heat waves would result in more people staying hot for longer periods of time. 

What's worrying about these new findings is that while past studies have shown heat waves getting worse, this one goes even further. It's not just about the temperature and where it's hot, but also how long the scorching heat sticks around and how it moves across different parts of the world.

Heat waves are lasting longer

During the years spanning 1979 to 1983, the average duration of global heat waves stood at about eight days, researchers noted. 

However, from 2016 to 2020, this duration stretched to approximately 12 days, according to the study's findings.

Eurasia bore the brunt of longer-lasting heat waves, while Africa experienced the most significant deceleration in their movement. 

Conversely, as outlined in the study, North America and Australia witnessed the most notable increases in overall magnitude, encompassing both temperature and spatial coverage.

"This paper sends a clear warning that climate change makes heat waves yet more dangerous in more ways than one," said Lawrence Berkeley National Lab climate scientist Michael Wehner, who wasn't part of the research.

Have you noticed how hot it's been?

The study also looks at the changes in weather patterns that propagate heat waves. Atmospheric waves that move weather systems along, such as the jet stream, are weakening, so they are not moving heat waves along as quickly — west to east in most but not all continents.

RELATED: Why is it so hot?

In all weather science, it’s virtually impossible to directly attribute any individual phenomenon to a specific cause. Global warming's effect on the jet stream's position is a case in point.

However, human activities that release gases like carbon dioxide into the Earth's atmosphere are causing global temperatures to reach record highs. 

According to the European Union's Copernicus Climate Change Service, January 2024 was the world's warmest January on record.

READ MORE: January was the world's warmest on record, scientists say

The Associated Press contributed to this story.