by A. Watts, April 5, 2026 in WUWT

If you have been following the rapid expansion of AI infrastructure, you have probably seen the latest claims that data centers are now creating their own “heat islands” large enough to affect hundreds of millions of people. The narrative comes courtesy of a recent working paper, quickly picked up and amplified by Fortune in: Data centers are so hot their ‘heat island’ effect is raising temperatures up to 6 miles away, which presents the findings in a way that suggests a new and potentially significant environmental driver emerging from the digital economy.

According to the article, researchers examined more than 6,000 data centers worldwide and found that surrounding areas experienced an average land surface temperature increase of about 2°C over the period from 2004 to 2024, with some locations showing increases as high as 9°C. The reported influence extends outward roughly six miles from facilities, and when combined with population maps, the authors estimate that as many as 343 million people could be affected These are large numbers, and presented without context they give the impression of a widespread and growing climate signal tied directly to AI infrastructure.

The underlying paper, however, tells a more nuanced story. The key variable being analyzed is not air temperature in the meteorological sense, but land surface temperature derived from satellite observations. That distinction matters because land surface temperature is extremely sensitive to local surface characteristics. Replace vegetation with buildings, pavement, and industrial equipment, and the measured surface temperature will rise, regardless of whether the underlying atmospheric conditions have changed in any meaningful way.

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