How El Niño shapes the world’s weather trends

This episode of Science Friday explores the science and global impacts of El Niño, with a focus on the potential for a 'super El Niño' event in 2026. Host Ira Flatow is joined by Dr. Dylan Amaya, a research scientist at NOAA’s Physical Sciences Laboratory, who explains that El Niño is defined by a warming of the eastern equatorial Pacific by more than 0.5°C over five consecutive three-month periods. The episode details how El Niño disrupts global weather patterns by shifting rainfall, altering atmospheric circulation, and influencing jet streams, leading to wetter conditions in the American Southwest and drier conditions in the Pacific Northwest. Dr. Amaya emphasizes that while El Niño is not a storm, it’s a large-scale climate shift with far-reaching effects, including exacerbating marine heat waves that threaten coral reefs and marine ecosystems. The discussion also touches on the role of climate change in amplifying El Niño intensity and the potential for such events to push vulnerable ecosystems toward irreversible tipping points. The episode concludes with an update on model confidence—now 80–100% that an El Niño will occur, though its strength remains uncertain, with official confirmation expected in the fall.