Extreme heat driven by the current powerful El Niño could cause approximately 451 thousand additional deaths worldwide over the next six months. This forecast was prepared by researchers from the Climate Impact Lab at the University of Chicago and the University of California, Berkeley, according to The Guardian.

According to their estimates, the highest number of losses is expected in Nigeria, Indonesia, Sudan, India, and Brazil. Around 3500 additional deaths are projected for the United States.

El Niño is a natural climate phenomenon in which surface water temperatures in the central and eastern tropical Pacific rise, altering weather patterns across many regions of the globe. The risks extend beyond heat: the phenomenon can intensify droughts, wildfires, and floods.

The projections cover the period from September 2026 to February 2027. Researchers estimate that heat-related excess mortality could persist until June or July.

To make the forecast, experts used data on the relationship between temperature and excess mortality across 24 378 regions worldwide from 1996 to 2025 and compared them with temperature change projections associated with El Niño.

The authors emphasize that the figure of 451,000 is a projected estimate rather than an exact count of future deaths. They suggest using it to prepare protective measures, such as improving heat forecasting, opening cooling centers, bolstering medical services, and protecting outdoor workers.

The current El Niño has already reached record temperatures for this phenomenon, months ahead of its expected peak. At the same time, global warming is occurring against the backdrop of a natural climate cycle and may be intensifying its effects.