Strong El Nino Could Bring More Than 450,000 Additional Heat Deaths

More than 450,000 additional heat-related deaths could occur worldwide through February 2027 as an unusually strong El Nino drives higher temperatures, according to a research report from the University of Chicago’s Climate Impact Lab.

The researchers estimate that global land temperatures could rise by about 1.2 degrees Celsius compared with a typical year. They also project that extremely hot days could occur 44 percent more often than in an average year.

The report said poorer countries and Africa’s Sahel region are likely to experience the heaviest impacts. It projected about 66,800 additional deaths across the Sahel, while Nigeria was given the highest projected toll for a single country, at 31,400.

Disproportionate impact in poorer regions

Indonesia was projected to record 19,300 additional deaths and Sudan 17,600. The Philippines, Vietnam, Thailand and Cambodia were forecast to experience a combined 19,400 additional deaths.

The report also projected 15,800 additional deaths in India and 13,300 in Brazil. The figures are estimates of deaths attributable to additional heat compared with what would be expected in a typical year, rather than reported fatalities.

Michael Greenstone, co-founder of the Climate Impact Lab and a co-author of the study, said heat risks are greatest in places that are already hot and have lower incomes.

“If you’re already in a hot place, the extra couple of degrees are going to be much more dangerous,” Greenstone said.

He said richer areas generally have better access to air conditioning, reliable water supplies and health services, which can reduce exposure to extreme heat.

Risks may continue beyond February

The El Nino event began developing in June and was expected to be one of the strongest on record. The United Nations’ weather agency reported in early September a 100 percent likelihood that the pattern would continue through February 2027.

Researchers said the dangers could persist into mid-2027, while Greenstone said heat risks could extend beyond the El Nino event and affect the following summer.

El Nino is a naturally recurring weather pattern. Experts cited in the report said climate change is intensifying its effects.

Abhiyant Tiwari, a heat specialist at NRDC India, said the projections should prompt stronger action. He added that funding and implementation remain weaknesses, including in India, despite the country having formal plans to address heat risks.

“The real measure of our preparedness is not how many heat warnings we issue, but how effectively we protect people and reduce preventable deaths,” Tiwari said.