Nigeria could record the highest number of excess heat-related deaths globally over the next six months if an expected “super El Niño” produces the extreme temperatures projected by researchers.

Researchers at the University of Chicago’s Climate Impact Lab estimate that extreme heat linked to the weather phenomenon could contribute to about 451,000 additional deaths worldwide between September 2026 and February 2027.

Nigeria alone is projected to account for about 31,400 of those deaths, putting the country ahead of other nations identified as being at high risk.

The researchers said the number of extremely hot days could increase by 44 per cent above normal levels, raising the risk of heat-related illness and death, particularly in vulnerable populations.

Indonesia is projected to record about 19,300 excess deaths, while Sudan could see an estimated 17,600. Across the Sahel, including Nigeria, Niger, Chad and Sudan, the projected additional fatalities could reach 66,800 during the six-month period.

Countries in Southeast Asia are also expected to face significant risks, with the Philippines, Vietnam, Thailand and Cambodia projected to record a combined 19,400 excess deaths.

The Climate Impact Lab warned that the figures could increase if the El Niño conditions persist into 2027, potentially exposing parts of the northern hemisphere, including India and Pakistan, to severe heat during their summer months.

The researchers described the current El Niño as a warning of what could become increasingly common as global temperatures rise, urging governments to begin targeted emergency measures in areas facing the greatest risks.

“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,” said Michael Greenstone, economist at the University of Chicago and co-founder of the Climate Impact Lab.