Should we be worried about El Niño? The phenomenon is a naturally occurring part of what is known as the ENSO cycle (the El Niño Southern Oscillation) and happens every two to seven years. The US National Oceanic and Atmospheric Administration (NOAA) and other scientific agencies declare an official El Niño event once Pacific Ocean temperatures are 0.5 degrees higher than normal, alongside weakening trade winds. While it usually brings changes to rainfall patterns across the tropics, leading to droughts and flooding – sometimes catastrophically so – the 2026-2027 El Niño is taking place on a planet that is already over 1 degree hotter due to human-caused global warming.

With a temperature anomaly of 2 degrees already in parts of the eastern Pacific by July 2026, this year’s El Niño looks on track to have no precedent in living memory. But while the ENSO cycle is natural, it is being turbocharged by global heating, in particular ocean warming. A team of scientists led by Columbia University’s James Hansen published an analysis last week that claimed the abnormal “Super-Duper El Niño” strength is “likely human-driven”.

As far back as 2014 a study published in Nature Climate Change reported that the frequency of extreme El Niño events would double in response to global heating. A research article published in Science last week found that El Niño events over the past 40 years have grown roughly 40 per cent stronger than those seen during........

© The Irish Times