“Super” El Nino: Causes and Consequences of This Winter’s ENSO Pattern By Sara Torres

Image Credit: World Meteorological Organization

The National Oceanic and Atmospheric Administration (NOAA) recently issued an advisory for a strong El Niño event this year, expected to peak from November to January. El Niño is a phase of the El Niño Southern Oscillation (ENSO) cycle, which occurs when surface temperatures in the equatorial Pacific exceed 0.5°C above average. NOAA's Oceanic Niño Index has tracked an anomaly of +1.7°C as of June 17, 2026, and experts anticipate it will strengthen in the coming months. Some researchers have already dubbed this year's event a "Super" El Niño, with the potential to bring widespread impacts on weather patterns across the globe.

What’s Driving This Year’s Event

El Niño occurs every two to seven years when trade winds weaken due to pressure changes. As a result, there’s less upwelling of cooler, nutrient-rich waters that stabilize air temperatures. El Niño is a natural phenomenon, and is not inherently tied with anthropogenic activity. However, this year’s event is predicted to be supercharged by climate change, as warmer global temperatures exacerbate the impacts of extreme weather events. Scientists are still studying this linkage, which has proven to be difficult due to the infrequency of El Niño events and their wavering nature. The Intergovernmental Panel on Climate Change believes there will be an increase in strong El Niño and La Niña events over the next century, generating devastating consequences for humans and wildlife.

El Niño impacts each region differently, and its exact results vary from year to year. In the United States, El Niño is felt most strongly during the winter months. The West Coast is typically at risk for flooding and algal blooms, while the South may experience more rain and snow during storms. Globally, parts of Africa, Southeast Asia, and Australia are at risk for heatwaves and droughts that are already building up.

Economic Fallout

The anticipated droughts from El Niño are sparking concerns about agricultural production, especially with many farmers already struggling with fertilizer and diesel shortages induced by the Iran War. Analysts and traders across Indonesia, Thailand, India, and Australia are reporting reduced planting by farmers as they grapple with limited resources. This is contributing to the financial trend commonly seen in El Niño years which encompasses major losses from lower crop and fishery yields, as well as disaster relief costs. In the past month, Thai rice prices have risen about 15%, foreshadowing price increases that may soon be seen for various crops produced in Southeast Asia.

El Niño events have historically caused trillions of dollars in global income losses, and experts believe this year’s event may be the costliest on record. Losses stem from immediate damages paired with long-term impacts such as interrupted labor, interrupted childhood development, and disruptions to the transport sector. Dartmouth University Professor Justin Mankin, who specializes in El Niño’s economic impacts states that, “costs accrue over years and disproportionately impact countries whose weather and climate is most tied to El Niño.”

Marine Ecosystem Impacts

In addition to terrestrial disruptions, marine ecosystems undergo significant changes during El Niño seasons. Decreases in equatorial upwelling reduce phytoplankton populations at the base of the food web, threatening vulnerable species such as sea lions, seabirds, and reef-building corals. In 2023, El Niño led to a 50% decrease in Peruvian anchoveta landings, hindering local fisheries and global supply chains that are dependent on fish oil and fishmeal for aquaculture. The interconnected nature of the marine food chain facilitates vast changes for ecosystems and the people that rely on them. Many marine species will alter their habitats, as demonstrated by a major increase in squid off the Oregon coast in 2015, while California’s squid landings decreased by more than half. Many fisheries will need to be flexible with their production over the following months, with species changing course and altering their yields. 

Looking Ahead

U.N. Secretary General António Guterres acknowledged that this year’s El Niño event will “pour fuel on the fire of a warming world”, believing that “the only effective response is climate action equal to the crisis – ending the addiction to fossil fuels, accelerating the shift to renewables, protecting the most vulnerable, and delivering early warning systems for all.” While the exact timing and impacts of ENSO patterns are unpredictable in the upcoming years, the only way to mitigate the consequences is by reducing extreme warming patterns driven by climate change.