WASHINGTON: Half the global population endured an additional month of extreme heat over the past year because of manmade climate change, a new study found Friday.

The findings underscore how the continued burning of fossil fuels is harming health and well-being on every continent, with the effects especially under-recognised in developing countries, the authors said.

“With every barrel of oil burned, every tonne of carbon dioxide released, and every fraction of a degree of warming, heat waves will affect more people,” said Friederike Otto, a climate scientist at Imperial College London and co-author of the report.

The analysis — conducted by scientists at World Weather Attribution, Climate Central, and the Red Cross Red Crescent Climate Centre — was released ahead of global Heat Action Day on June 2, which this year spotlights the dangers of heat exhaustion and heat stroke. To assess the influence of global warming, researchers analyzed the period from May 1, 2024 to May 1, 2025.