El Niño heat projections place poorest countries at greatest risk

An unusually strong El Niño could be linked to more than 450,000 additional heat-related deaths worldwide over the six months to February 2027, according to a report published by the University of Chicago’s Climate Impact Lab. The figure compares projected deaths with levels expected in a typical year; it is an estimate, not an observed toll.

The report estimates global land temperatures could rise by about 1.2°C, with extremely hot days 44 per cent more frequent than in an average year. It projects about 66,800 additional deaths across Africa’s Sahel region. Nigeria has the highest projected toll for a single country, at 31,400, followed by Indonesia at 19,300 and Sudan at 17,600.

The researchers expect poorer countries to bear disproportionate harm. Lab co-founder Michael Greenstone said heat poses the greatest threat where temperatures are already high and incomes relatively low. He pointed to greater access to air conditioning, reliable water and health services in richer places.

Other projections include 19,400 additional deaths combined across the Philippines, Vietnam, Thailand and Cambodia, 15,800 in India and 13,300 in Brazil. The report does not provide uncertainty ranges for these estimates.

El Niño began developing in June and is expected to be one of the strongest on record. The natural weather pattern is being intensified by climate change, according to experts cited in the source report. In early September, the United Nations’ weather agency said there was a 100 per cent likelihood the event would continue through February 2027.

Researchers say heat risks could persist into mid-2027. Abhiyant Tiwari, a heat specialist at NRDC India, said preparedness should be measured by how effectively people are protected and preventable deaths reduced, rather than by the number of warnings issued.