The Climate Impact Lab at the University of Chicago used temperature‑mortality data from 24,378 regions to estimate excess deaths that could result from the El Niño compared with the 1996‑2025 average, and the findings will appear in a peer‑reviewed journal.
Declared in June and expected to peak later in 2026, this El Niño is on track to become the strongest on record, intensifying the impacts of human‑induced climate change.
The study indicates that developing countries will suffer the greatest toll. In Africa’s Sahel region, an additional 66,800 heat‑related deaths are projected, with nearly half of those expected in Nigeria alone.
Other hotspots include Indonesia with an estimated 19,300 extra deaths, and a combined 19,400 in the Philippines, Vietnam, Thailand and Cambodia. India could see about 15,800 additional deaths, while Brazil may face roughly 13,300.
Researchers expect global land temperatures to be about 1.2 °C above normal in the coming months, which would generate 44 % more extremely hot days than in a typical year.
The lab says its projections can help governments and humanitarian organisations take preventive actions such as heat‑wave warnings, cooling centres and hydration stations. “This report allows decision‑makers to see exactly where emergency actions can be taken now to save tens of thousands of lives in the coming months,” co‑founder Michael Greenstone said.
The report follows a United Nations warning issued a day earlier that El Niño poses a significant threat to global health.