The past 40 years brought the strongest El Niños in a millennium
A thousand-year temperature series built from Galápagos corals finds that major El Niños in the past 40 years were about 40 per cent stronger than preindustrial events. Two reports published the same day trace consequences at other scales: an ice-and-rock collapse triggered a deadly flood on the Nepal–Tibet border, while an analysis of 916,404 Chicago emergency and urgent-care visits found several diagnoses became more common above 33.7 °C.
Science··Night
A millennium of temperature in coral
Julia Cole and colleagues at the University of Michigan used 13 coral samples from the Galápagos Islands to extend eastern Pacific sea-surface temperatures back a millennium. Their analysis finds that major El Niños in the past 40 years were about 40 per cent stronger than preindustrial counterparts. Climate models did not reproduce this strengthening from natural variability alone. If the sampled sites represent the wider eastern Pacific, that mismatch could reflect an influence beyond natural variability; if the sites do not represent the region, an alternative explanation is that the apparent regional strengthening reflects the sampling.[1]
Ice and rock collapse in Nepal
On 26 August, an ice-and-rock collapse on the Nepal–Tibet border formed a temporary lake whose release sent rock, mud and water down the valleys. Around 350 people died and more than 1,000 remain missing. The Trishuli River rose by as much as 9 metres in 30 minutes at Galchhi. The absence of a large pre-existing glacial lake in satellite imagery or extreme rainfall in weather data weakens the first explanation, while global warming's contribution to the collapse has yet to be established.[2]
Patterns of illness in Chicago heat
Researchers scanning 916,404 emergency-department and urgent-care visits in Chicago from 2011 to 2023 found kidney and skin complaints and several injuries became more common when daily temperatures exceeded 33.7 °C. Accidental gunshot wounds showed the largest relative shift, rising more than 30-fold on hot days. The study covers one city and tests many diagnostic categories at once; these associations do not establish that heat caused any individual condition.[3]
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