Summary
A strengthening El Niño has already disrupted Peru’s anchovy fishery and contributed to drought, flooding and crop losses across several regions. Forecasts suggest this eastern Pacific event could become unusually intense as it combines with ongoing global warming.
A strengthening El Niño is already disrupting fisheries, agriculture and transport across several regions, while forecasts suggest the event could become one of the strongest in centuries. The eastern Pacific event is developing against a much warmer global background, making its eventual weather patterns harder to predict from past El Niños alone.
In late August, Peru ended its anchovy fishing season early after warmer Pacific waters pushed full-grown anchovies into deeper, colder areas in search of food. The fishery normally produces millions of tonnes of anchovies each year for use in fertilizer and animal feed.
The event is also contributing to a familiar but uneven El Niño pattern: drier conditions in areas around the equator, Central America and the western Pacific, alongside heavier rain in parts of the Horn of Africa, the western United States and the Pacific coast of South America.
Why this El Niño is unusual
El Niño begins when sea-surface temperatures in the tropical Pacific become unusually warm. The warmer ocean heats the atmosphere above it, changing winds and shifting weather patterns far beyond the Pacific.
The effects depend on where the warming is concentrated. Events dominated by the central Pacific can influence weather differently from those centred in the eastern Pacific. Strength also matters: a strong event can produce patterns that are unlike those associated with a moderate El Niño.
Scientists quoted in the report describe the current event as the first strong eastern Pacific-flavoured El Niño since the late 1990s. It also strengthened earlier than comparable strong events in 1997 and 2015. That leaves relatively little direct precedent for how this particular ocean pattern will interact with almost three decades of additional global warming.
Some forecasts suggest the event could become the strongest in centuries. Other projections indicate that the combination of El Niño and the warmer climate could push global average temperatures in 2027 to record levels. Those are forecasts rather than established outcomes, and their confidence depends on how the event develops.
Early effects across regions
The emerging impacts broadly resemble those seen during previous strong El Niños, but they are already affecting important food, water and transport systems.
Drought in Central America has slowed shipping through the Panama Canal, whose locks require freshwater to move vessels between elevations. Crop losses have also been reported by smallholder farmers in Guatemala, Honduras and El Salvador. In the Caribbean, drought has contributed to water rationing in Puerto Rico and crop stress in Jamaica.
Dry conditions around the equator have helped produce an above-average start to Indonesia’s wildfire season. India has experienced lower-than-average monsoon rainfall while flooding has affected some areas, another combination that can occur during El Niño. In parts of southern and eastern Africa, dry weather alongside high fuel and fertilizer prices is increasing pressure on food supplies. A United Nations World Food Programme projection cited in the report said tens of millions of people in the region could face acute food insecurity because of the event.
The opposite pattern is affecting other regions. Heavy rain and snow in Chile and Peru have caused flooding, disrupted copper mining and led to the closure of Machu Picchu. The Horn of Africa is forecast to face flooding similar to the 2023 El Niño, an event that displaced millions of people.
The developing event therefore matters not only because of a possible temperature record. Its effects can propagate through fisheries, farming, water supplies, shipping, mining and food security. The distribution of impacts will depend on the event’s final strength and on which parts of the Pacific remain warmest.