Super El Niño 2026: Up to 451,000 heat-related deaths projected worldwide

Thursday 24 September 2026 - 23:40

A powerful El Niño episode developing across the Pacific could intensify heat-related health risks around the world, with as many as 451,000 additional deaths potentially occurring between September 2026 and February 2027, according to an estimate from the Climate Impact Lab.

The figure represents a projection rather than a confirmed death toll. Researchers are comparing the number of heat-related deaths expected during the unusually strong climate event with the level that would normally be recorded during an average year.

A potentially exceptional El Niño event

El Niño is a naturally occurring climate pattern associated with unusually warm surface waters in the equatorial Pacific Ocean. It typically develops every two to seven years and can influence temperature and rainfall patterns far beyond the Pacific region.

The current episode is attracting particular attention because of its projected intensity. The U.S. National Oceanic and Atmospheric Administration (NOAA) has estimated a probability of more than 90% for a very strong El Niño during the autumn and winter of 2026-2027.

Ocean surface temperatures in parts of the equatorial Pacific were already more than 3°C above average in September, according to the information cited in the projection. NOAA's geophysical modelling has also pointed toward an unusually powerful event, although the exact strength of the peak remains uncertain.

Africa and the Global South face significant risks

The projected health impact is expected to be particularly pronounced across tropical regions and several countries in the Global South.

Estimates from the Climate Impact Lab, as reported by Reuters, indicate that Nigeria could experience about 31,400 additional heat-related deaths during the six-month period. Indonesia follows with an estimated 19,300 deaths, while Sudan could record around 17,600.

Across the Sahel, the projected additional toll reaches approximately 66,800 deaths, highlighting the vulnerability of populations already exposed to high temperatures and difficult environmental conditions.

Other heavily exposed countries include India and Brazil, as well as several nations in Southeast Asia. The Philippines, Vietnam, Thailand and Cambodia could collectively account for roughly 19,400 additional heat-related deaths during the period covered by the study.

The risks extend beyond extreme temperatures

Heat is the main factor behind the Climate Impact Lab's estimate, but a severe El Niño can trigger a wider chain of environmental consequences.

Changes in rainfall can increase the likelihood of drought in some areas while raising flood risks elsewhere. Prolonged dry conditions can also contribute to wildfires, while altered weather patterns can place additional pressure on agriculture, water supplies and public health systems.

Researchers describe the projected conditions as a glimpse of climate conditions that could become more familiar in the coming decades as global temperatures continue to rise.

Preparing before extreme heat arrives

Scientists stress that the projected figure should not be interpreted as an unavoidable outcome. Instead, it can serve as an early warning for governments and health authorities.

Measures such as cooling centres, heat-alert systems, stronger emergency health services and additional protection for outdoor workers can help reduce exposure during periods of extreme heat. Special attention may also be required for older people, people with existing vulnerabilities and communities with limited access to cooling.

The projection therefore offers authorities an opportunity to identify areas at greatest risk and prepare interventions before the most dangerous conditions occur.

As El Niño develops, the effectiveness of early action could become a decisive factor in determining how many lives are ultimately affected by the coming period of extreme heat.