Super El Niño Could Cause 55,000 Extra Heat Deaths in India by March 2027: What the New Projection Means
The Climate Impact Lab at the University of Chicago estimates that the 2026 super El Niño could cause about 55,000 additional heat-related deaths in India between October 2026 and March 2027. Most of these deaths are expected in March 2027.
This is nearly four times the lab's earlier estimate of 15,800 deaths for India (September 2026 report, covering September 2026 to February 2027). The estimate went up because March is now included and because August and September were much hotter than forecast.
Worldwide, the lab now projects about 857,000 additional heat deaths linked to this El Niño from June 2026 to March 2027, up from 451,000 in its September report. For October 2026 to March 2027, Nigeria (about 56,000) is first and India is a close second.
According to the Copernicus Climate Change Service, August 2026 was the warmest August on record, and September 2026 was the second-warmest September, at 1.63°C above the pre-industrial level (1850-1900).
The lab also launched an El Niño Heat Mortality Tracker, which gives monthly death projections up to six months ahead, with state and province-level data, to help governments plan early.
The researchers warn that heat of this kind, which today comes with a strong El Niño, could become normal within about 20 years.
El Niño–Southern Oscillation (ENSO)
El Niño–Southern Oscillation, or ENSO, is a natural climate "swing" in the tropical Pacific Ocean. Every few years, the surface of the central and eastern Pacific becomes unusually warm (El Niño) or unusually cool (La Niña). The winds and air pressure above the ocean change along with it, and this disturbs weather across the world, including India's monsoon and temperatures.
The extra heat deaths projected for India are linked to the very strong 2026 El Niño. Because the warming effect reaches its peak a few months after the Pacific peaks, India's highest risk is expected in March 2027, when the pre-summer heat begins.
Heatwave in India: IMD Criteria and Heat Action Plans
A heatwave is a period of unusually high air temperature that is much hotter than normal for that place and time of year, and that lasts for some days. It is dangerous because the human body can only cool itself up to a limit. India is one of the countries most exposed to heatwaves, mainly from March to June. In India, the India Meteorological Department (IMD) decides when a heatwave is declared, and Heat Action Plans at the city, district and state level decide how to protect people.
The projected 55,000 extra deaths show the human cost when a strong El Niño pushes India's temperatures far above normal. Most deaths are expected in March, before the usual heatwave season, which means heat action plans and early warnings must start earlier than usual. The new notified-disaster status of heatwaves gives states regular funds to prepare.
Paris Agreement Temperature Goal and the 1.5°C Threshold
The Paris Agreement, adopted in 2015, is the world's main climate treaty. Its central aim, in Article 2.1(a), is to keep the rise in the Earth's average temperature well below 2°C above pre-industrial levels and to pursue efforts to limit it to 1.5°C. "Pre-industrial" means the period 1850-1900, before large-scale burning of coal, oil and gas.
The researchers say this El Niño gives a preview of the heat that could become normal within about 20 years. That is roughly when the long-term global average is expected to cross 1.5°C, so the deaths projected now point to the risks of missing the Paris goal.
- Projected extra heat deaths in India: about 55,000 (October 2026 to March 2027); most in March
- Earlier India estimate: 15,800 (September 2026 report, September 2026 to February 2027)
- Global projection: about 857,000 additional heat deaths (June 2026 to March 2027), up from 451,000
- Global projection for October 2026 to March 2027: about 373,000; Nigeria first (about 56,000), India second
- Source of projection: Climate Impact Lab, University of Chicago; new El Niño Heat Mortality Tracker (monthly forecasts, up to six months ahead, state-level data)
- August 2026: warmest August on record (Copernicus C3S, run by ECMWF)
- September 2026: second-warmest September; global average 16.27°C, 0.82°C above 1991-2020 average and 1.63°C above 1850-1900
- Researchers warn similar heat risks could become common within about 20 years