India could see an estimated 15,800 additional heat-related deaths, give or take 1,600, between September 2026 and February 2027, as the current ‘Super El Niño’ drives unusually high temperatures, according to a report made public on Wednesday (September 23, 2026) by the Climate Impact Lab. The estimate is relative to average conditions during the corresponding months from 1996-2025.
Globally, the report projects 451,000 additional heat-related deaths during the first six months of the El Niño event, including 239,000 during the September 2026-February 2027 period. It projects 19,300 deaths in Indonesia; 19,400 across the Philippines, Vietnam, Thailand, and Cambodia; 13,300 in Brazil; and 66,800 across the Sahel, a 5,000-kilometre swathe of about 10 countries across Africa, including Senegal, the Gambia, and northern Nigeria.
“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,” Michael Greenstone, co-founder, Climate Impact Lab, University of Chicago, said.
The report describes the current event as a ‘Super El Niño’, an informal term generally used for exceptionally strong El Niño conditions. El Niño occurs when waters in the central and eastern tropical Pacific become unusually warm, altering atmospheric circulation and shifting rainfall and temperature patterns worldwide. Forecasts earlier this month projected a greater than 90% chance of a very strong El Niño during the northern hemisphere autumn and winter, with eastern equatorial Pacific sea surface temperatures already more than 3°C above normal.

Its effects are already being observed in different regions. Indonesia has experienced conditions conducive to wildfires, while parts of Central America have faced drought-related agricultural impacts. “This year’s El Niño is also a ‘postcard from our future’, bringing temperatures climate change is projected to deliver 20 years in the future. In this way, it offers a glimpse at what lies ahead without new investments in adaptation,” an accompanying press statement noted.
In India, the southwest monsoon is entering its withdrawal phase after a season marked by deficient rainfall. The national rainfall deficit stood at about 15% below normal up to September 22, 2026 with larger shortfalls in southern and eastern parts of the country.

The heat is also increasing the demand for electricity, with nearly 40% of India’s coal-fired power plants reporting critically low fuel stocks amid increased power demand associated with hotter than usual weather linked to the El Niño.
The study’s mortality estimate, however, comes with methodological limitations. The Climate Impact Lab says it applies previously estimated temperature-mortality relationships across 24,378 regions to seasonal temperature forecasts, accounting for local climate, vulnerability, and adaptive capacity. The report does not spell out the underlying numerical relationship or coefficients connecting a particular temperature increase to a number of deaths; it says full methodological details will appear in a forthcoming peer-reviewed paper.
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Previous research has established an association between extreme heat and mortality. A 2024 multi-city study found heatwaves were associated with increased all-cause mortality across 10 Indian cities, while a global study estimated India accounted for about 20.7% of heatwave-related excess deaths during 1990-2019.
Absolute death totals also tend to be higher in more populous countries because more people are exposed, although population alone does not determine the burden — temperature, vulnerability, age structure, and adaptive capacity also matter. The summer heatwave across large parts of Europe killed at least 36,000 this year though the direct effects of an El Niño aren’t registered in the continent as much as in tropical countries.
Earlier this week, 188 Indian scientists and ecologists called for expanded monitoring of the El Niño’s effects on India’s marine, freshwater, and terrestrial ecosystems. “We need to mobilise resources now to design, deploy, and evaluate the preparation and planning tools that will save lives in the years ahead,” the release said.
Published – September 23, 2026 10:43 am IST