Scientists find new clue to predict when next El Niño will strike

Predicting El Niño a year in advance could help communities and decision makers better prepare for the weather phenomenon’s impact.

This year’s El Niño could be “literally off the monitoring charts” as the UN weather agency warns its impacts will extend into 2027.

The natural weather phenomenon, which typically occurs every two to seven years, is still intensifying in the Pacific – driving extreme weather across Central America’s Dry Corridor, which stretches from Mexico to Panama, and threatening coral reefs and forests.

“The current El Niño event could be unprecedented in strength,” Celeste Saulo, secretary-general of the World Meteorological Organization (WMO), told reporters in Geneva earlier this week. “This will have far-reaching consequences for weather patterns across the world.”

Tom Fletcher, the UN’s under-secretary-general for humanitarian affairs, described El Niño as a “wrecking ball” of extreme heat, drought and flooding, warning it would bring “massive humanitarian consequences”.

But communities and decision-makers may soon be able to better prepare for the wrath of El Niño – and its cooler counterpart La Niña – thanks to a new breakthrough.

Can we predict future El Niños?

Researchers from CSIRO, Australia’s national science agency, and the University of Melbourne have just identified the conditions that make it possible to predict some El Niño and La Niña events up to a year in advance.

El Niño–Southern Oscillation (ENSO) events like El Niño and La Niña typically peak around December and can usually be forecast with confidence around six months in advance. Predicting them earlier has long been a challenge.

But after analysing more than 7,500 historical ENSO forecasts from climate models developed in nine countries, scientists found that knowing whether the Pacific is in an El Niño, La Niña or neutral state when a forecast is started can provide valuable clues about how reliable a forecast is likely to be 12 months later.

The study, published in the journal Science Advances, found that forecasts initiated during La Niña conditions consistently performed well even when predicting ENSO events a year ahead, while forecasts beginning from neutral conditions were far less reliable.

Co-author Dr Mandy Freund from the University of Melbourne and researcher with the Australian Research Council Centre of Excellence for 21st Century Weather, says that the findings provide a new way to assess confidence in long-range climate forecasts.

“We’ve known for some time that the starting conditions affect how well model forecasts perform, but our study really shows how drastic those differences in performance can be,” explains Lead author Dr Nandini Ramesh.

“The exciting thing about our results is that we can use that information. We can identify which forecasts deserve greater confidence and potentially warn the public about El Niño events much earlier.”

The breakthrough could help improve how early warnings are communicated. However, Dr Ramesh, a senior research scientist at CSIRO, says the team is still a “few steps away” from applying the findings to the models used by forecasting agencies.

“But these results hold promise for being able to communicate early warnings for future events,” she adds.

How can the world prepare for El Niño?

El Niño is a natural phenomenon, meaning it can’t be stopped. However, wide forecasts will give countries longer to prepare.

“The key is to manage water and prepare for the changes in where and when rainfall occurs,” says Davide Faranda, research director at France’s National Centre for Scientific Research (CNRS).

For example, Faranda explains, governments can store and distribute water more carefully, better control how reservoirs and underground water are used, adjust farming schedules and irrigation practices, and prepare communities for droughts or floods.

Farmers can also reduce their losses by changing planting dates, irrigating at cooler times of day, storing water ahead of droughts and taking steps to protect their crops and livestock from extreme heat.

Tackling climate change could help limit future damage too. While El Niño events can increase global average temperatures by around 0.2°C – enough to trigger widespread destruction – the burning of fossil fuels has added considerably more heat into the atmosphere.

El Niño’s impacts are therefore compounded by an already warming world. It’s why 2025 was the third warmest year on record – hotter than the El Niño year of 2016 – despite the naturally forming cool drag of a La Niña event.

“We cannot eliminate El Niño through climate mitigation,” Faranda says, “but we can reduce the extent to which climate change makes its consequences more severe.”

Source: www.euronews.com