What a record-breaking El Nino could mean for the world

This year's El Niño is poised to be the strongest on record, potentially bringing extreme weather worldwide and making 2027 the hottest year ever recorded. As the head of long-range forecasting at the U.K.'s Met Office warns, this intense El Niño, the most powerful in over a century, will provide a glimpse of the heat the world may experience by the late 2030s.

El Niño, the warming phase of the natural El Niño-Southern Oscillation (ENSO) cycle, occurs when trade winds weaken, allowing warm water to shift eastward, resulting in warmer-than-average surface temperatures. This amplifies storms and clouds, leading to varying weather patterns globally. In Indonesia, for instance, the prolonged dry season has fueled devastating wildfires.

While some effects are already apparent, experts caution that not all outcomes are guaranteed. Daily sea surface temperatures in the Niño 3.4 region are currently about 2.6C above the 30-year average, with forecasts suggesting the El Niño could peak at a 3.9C anomaly this November, potentially surpassing the 2024 record and setting the stage for 2027 to claim the top spot.

Climate scientists project that El Niño will add a temporary 0.3C to the long-term global warming trend, resulting in 2027 temperatures 1.76C above preindustrial levels. This represents the warming that would typically occur by 2037, compressing it into a single year. Mike McPhaden of NOAA's Pacific Marine Environmental Laboratory estimates that it's conceivable for 2027 to exceed 1.7C above preindustrial levels if model forecasts hold true.

Although not all scientists agree on whether climate change directly triggers stronger El Niños, evidence suggests that our warming atmosphere holds more moisture, making El Niño-linked rains more extreme and drying out soils, amplifying droughts in affected regions.