A new study reports that global exposure to dangerous heat stress has increased substantially since the 1970s. The research finds that the share of the world’s population facing at least one day of extreme heat stress each year rises from 16% to 22% over roughly the past half century. That increase is described as equivalent to about one billion more people living in areas where extreme heat stress occurs annually. The study attributes the trend to climate change, noting that rising temperatures increase the likelihood and intensity of heat conditions that can be harmful or dangerous to humans.
Several outlets highlight the findings in the context of ongoing heat across different regions, including recent heat waves in Europe. While the reports focus on different phrasing—such as “dangerous heat stress” and “extreme heat stress”—they refer to the same central results: a long-term upward shift in how many people experience extreme heat stress each year and a climate-driven explanation for the broader global rise.
