Nigeria faces world's highest projected heat death toll from super El Niño

Researchers at the University of Chicago's Climate Impact Lab combined temperature forecasts with research on how heat affects death rates in more than 24,000 regions worldwide and found that the super El Niño could cause an estimated 451,000 additional heat-related deaths worldwide between now and February 2027.

Michael Greenstone was part of the research team, along with Tamma Carleton, Genevieve Maricle and Emily Grover-Kopec. He explains why Africa's Sahel region is projected to be the hardest hit and why Nigeria is projected to be one of the worst-hit countries. He also explains what governments need to do now to protect people there.

Which African countries face the greatest risk from El Niño's extra heat, and why?

Africa's Sahel region is projected to face the greatest loss of life from the heat brought on by this year's strong El Niño. The Sahel is a belt of dry land stretching across Africa from the Atlantic Ocean to the Red Sea, between the Sahara Desert in the north and tropical savannas in the south. It covers about 3.05 million square kilometers (1.18 million square miles) and cuts through parts of Mauritania, Mali, Niger, Chad, Nigeria, Sudan, Senegal and Eritrea.

Four countries are projected to be most affected by El Niño from September 2026 through the end of February 2027: Nigeria, Sudan, Niger and Chad.

In Nigeria , more than 60% of people were estimated to live below the national poverty line in 2025, while even homes with electricity face power cuts. In Sudan , war has destroyed businesses and jobs and damaged power supplies, with an estimated 57% of people living in extreme poverty in 2025. In Niger , 41% lived below the national poverty line in 2021.

In Chad , 44.8% of the population lived in poverty in 2022. Many people in Niger and Chad depend on farming, leaving them exposed to droughts and poor harvests. Only 21% of people in Niger and 13% in Chad had electricity in 2024, leaving most without power to run even a fan.

Our projections show that these four countries will likely see 66,800 additional deaths from extreme heat compared with a normal year. Nearly half of these deaths—31,400—are projected to be in Nigeria, the most populous of the four with 237.5 million residents . This makes Nigeria the country most likely to have the world's highest heat-related death toll under the super El Niño.

Sudan is projected to have the second-largest number of heat-related deaths at 17,500, followed by Niger with 10,000 and Chad with 8,000. Some of the largest temperature anomalies across the globe over the next six months will be across the Sahel, which is why the region faces greater impacts from the super El Niño than other regions.

Our research also projects that there will generally be more heat-related deaths in impoverished regions than in wealthier regions facing similar temperatures. This includes countries across the Sahel because low-income areas have fewer resources to protect people from extreme heat.

How did you estimate the likely deaths in African countries?

To estimate mortality (deaths) from this year's El Niño, we used the European Centre for Medium-Range Weather Forecasts' seasonal forecast to estimate how temperatures will differ from the norm over the next six months. We then used peer-reviewed Climate Impact Lab research to translate those temperature changes into projected heat-related deaths.

Our research looks at how temperature affects death rates in 24,378 regions, taking into account the local climate, people's risk and their ability to cope with heat. Our estimates show how many more or fewer heat-related deaths are expected compared with the average for the same months in 1996–2025.

Who is most at risk within these countries, and what can governments do now to protect them?

While our study did not directly address who is most at risk, there is already a large body of research on who is most affected by heat. Older people (>65 years old), children (0–4 years old) and people with chronic health conditions are at greater risk than other people around the world.

In Africa, people who work outdoors, such as farmers, and who lack indoor cooling face considerable danger. Much of Africa lacks the electricity needed for air conditioning.

We recently conducted other research on who can afford to stay cool as temperatures rise. It found that even as temperatures rise, people in low-income countries have very little extra electricity to cope with the heat. The extra electricity used per person during periods of high heat in low-income countries would be enough to run only one LED light bulb for four months—nowhere near enough to power an air conditioner.

We believe , based on this research, that as the world heats up, wealthier countries will use more air conditioning to cool down. Poorer, hotter countries will lack the money and reliable electricity needed to protect people.

There are 18 countries trapped in this deadly combination of extreme heat and lack of cooling. Most are in northern sub-Saharan Africa, including Niger, Mali, Burkina Faso and Chad. People in these countries will therefore be worst off when the super El Niño takes hold.

What steps could save the most lives quickly?

As part of our ongoing research, we have set up an Adaptation Inventory . This searchable world map shows what countries are doing to adapt to climate change and how heat warnings, drought-tolerant seeds and better access to health care can help.

We believe the most effective near-term solutions for this year's projected heat waves are those with proven track records, according to our Adaptation Inventory. They include early warning systems to alert people to extreme heat, paired with heat action plans to help people get out of the heat.

Other approaches that have worked include targeted health outreach to older and vulnerable people, government-run cooling centers and hydration stations in areas at high risk of extreme heat, and protections for outdoor workers during the most dangerous hours.

Governments in the Sahel region will likely have to prepare for more people with sunstroke and heatstroke in public hospitals. They can do this by hiring extra staff now, obtaining supplies and preparing hospitals for a surge in patients during the forecast heat spikes.