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The waters off the coast of Peru are normally one of the most productive fisheries in the world, each year producing millions of tonnes of anchovies to be used for fertilizer and animal feed. But in late August, the government cancelled the anchovy season early: the El Niño event gaining strength in the tropical Pacific Ocean has increased ocean temperatures and sent full-grown anchovies in search of food to deeper, colder waters, ruining the catch.
That is just one example of how this year’s monster El Niño is causing disruptions globally. Forecasts for the months ahead suggest that the impacts will be felt in many locations normally associated with El Niño’s influence, says Deepti Singh, a climate scientist at Washington State University in Vancouver. That includes drought in areas around the equator, Central America and the western Pacific Ocean, as well as extreme rainfall in the horn of Africa, western United States and the Pacific coast of South America.
But this El Niño is forecast to reach unprecedented strength. That, combined with the influence of global warming, could mean that the effects of this event look different from the strong El Niños of the past. “You change the patterns and the weather reacts,” says Eran Vos, a climate scientist at Bar-Ilan University in Ramat Gan, Israel.
Flavours of El Niño
El Niños occur when sea-surface temperatures in the tropical Pacific Ocean become abnormally warm. This affects air temperatures in the atmosphere above the region, shaping wind and weather patterns across the globe.
Not all El Niños have the same influence on weather. El Niños caused by warm ocean temperatures in the central Pacific behave differently to ones formed in the eastern Pacific. And weather patterns during strong El Niño events are different from those caused by moderate ones. “El Niños come in flavours, like ice creams,” says Jérôme Vialard at the Research Institute for Development in Marseille, France.
This event is the first strong El Niño with an eastern Pacific flavour since the late 1990s, says Vos. That means that there’s not a lot of precedent for how it will influence weather when combined with almost three decades of global warming.
There are a few other aspects that make this year unique. The El Niño has strengthened earlier than it did during previous strong events, such as the ones that occured in 1997 and 2015. Some forecasts suggest that this El Niño could become the strongest one in centuries, combining with background global warming to raise average temperatures in 2027 to record levels.
Dry and wet
Researchers say that, so far, the emerging effects of this El Niño resemble those of previous strong events.
Drought conditions in Central America have slowed shipping traffic on the Panama Canal, which uses freshwater to fill its locks for each passing ship. Tens of thousands of smallholder farmers in Guatemala, Honduras and El Salvador have reported crop losses. In the Caribbean, an historic drought worsened by climate change has intensified further, leading to water-rationing in Puerto Rico and crop stress in Jamaica.
This hot, dry pattern extends around the equator. Indonesia has seen an above-average start to the wildfire season. Meanwhile, India has had a lower-than average monsoon rainfall, even as flooding has hit some of the country — an expected effect of El Niño. In parts of southern and East Africa, dry weather combined with high prices for fuel and fertilizer is threatening food security. A June report from the United Nations World Food Programme projected that tens of millions of people in these regions will experience acute food insecurity due to the El Niño.
Meanwhile, other parts of the planet tend to see too much rain during El Niño events. Heavy rain and snow in Chile and Peru have caused flooding, disrupted copper mining and closed the Incan citadel Machu Picchu to tourists. The Horn of Africa is predicted to see flooding similar to what occurred during the 2023 El Niño, which displaced millions of people.
Changing influence
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Facts Only
* Waters off the coast of Peru are normally one of the most productive fisheries globally.
* The anchovy season was cancelled early in late August due to the El Niño event.
* The El Niño caused full-grown anchovies to seek deeper, colder waters.
* Forecasts suggest impacts will be felt in areas associated with El Niño influence.
* These predicted impacts include drought around the equator, Central America, and the western Pacific Ocean.
* Extreme rainfall is forecasted in the horn of Africa, the western United States, and the Pacific coast of South America.
* The El Niño has strengthened earlier than during previous strong events (1997 and 2015).
* Drought conditions slowed shipping traffic on the Panama Canal due to reduced freshwater supply.
* Tens of thousands of smallholder farmers in Guatemala, Honduras, and El Salvador reported crop losses.
* An historic drought worsened by climate change intensified in the Caribbean, leading to water rationing in Puerto Rico and crop stress in Jamaica.
* Indonesia experienced an above-average start to the wildfire season.
* India experienced lower-than-average monsoon rainfall despite some flooding.
* Dry weather combined with high fuel/fertilizer prices threatens food security in parts of southern and East Africa.
* Heavy rain and snow in Chile and Peru caused flooding and disrupted copper mining.
* The Incan citadel Machu Picchu was closed to tourists due to flooding.
* The Horn of Africa is predicted to see flooding similar to the 2023 El Niño.
Executive Summary
Full Take
The reality of this event lies not in a single physical outcome, but in the complex modulation of existing climate variables. The description of El Niños as having different "flavours" reflects a critical realization: the response of the climate system to warming is context-dependent. The emergence of an eastern Pacific flavored event, unprecedented when overlaid with multi-decadal global warming trends, suggests that historical precedent may be insufficient for predicting future systemic shifts. This challenges the assumption of linear extrapolation based on past strong events.
The ensuing terrestrial impacts—drought in Central America versus flooding in South America and Africa—demonstrate how an oceanographic driver translates into localized socio-economic crises. The juxtaposition of agricultural failure, displacement from natural resources (fisheries), and infrastructure damage (Panama Canal, Machu Picchu) reveals a systemic vulnerability where global oceanic thermodynamics immediately translate into acute human insecurity. What this pattern implies is that the stability of global systems is increasingly dependent on their capacity to absorb non-linear change without disproportionately affecting vulnerable populations across diverse geographic zones simultaneously.
What questions remain are about the speed and scale at which these regional divergences will converge or diverge under continued warming. How do current governance structures, which operate on localized scales, effectively manage a pattern where the rules of atmospheric physics themselves appear to be shifting in character? What are the second-order consequences when environmental pressures force simultaneous crises across food security, resource access, and geopolitical stability?