On a Monday morning in late summer, satellite instruments recorded the surface temperature at the heart of the Pacific's El Niño zone sitting 2.6°C above its 30-year average. That number, clinical and precise, conceals something extraordinary: the world may be watching the most powerful El Niño in recorded — and reconstructed — history take shape in real time. Climate analyst Zeke Hausfather, drawing on evidence from coral reefs, tree rings and historical documents, has concluded that no El Niño has reached this intensity in at least a millennium.

Forecasting models, averaging across 14 different projections, now expect the anomaly to peak at around 4°C in November — surpassing the previous satellite-era record of 3.1°C, set in 2015, with several months still to run. The consequences are already visible across two hemispheres. In Indonesia, worsening wildfires are scorching landscapes that have been weakened by drought.

In India, the monsoon rains on which hundreds of millions depend for food and water are losing strength. Looking further ahead, scientists anticipate heightened fire danger across Australia and more destructive flooding in parts of South America. The World Food Programme estimated in August that the El Niño is likely to drive approximately 50 million people into acute hunger — a figure that reflects not only crop failures but the cascading pressure on fragile supply chains. What makes this cycle particularly alarming is the feedback loop that researchers have recently identified: global heating, driven by fossil-fuel emissions, is now amplifying El Niño events, which in turn amplify the climate crisis itself.

Europe's deadliest heatwave on record killed at least 35,000 people this summer before the El Niño peak had even arrived.