NOAA's New Method Reveals More La Niñas and Fewer El Niños Ahead

The US National Oceanic and Atmospheric Administration (NOAA) has changed how it measures El Niño and La Niña events. The update comes as global warming speeds up shifts in weather patterns. Scientists expect the new method to identify more La Niña events and fewer El Niños in the future.

The adjustment follows years of record-breaking temperatures, including an unusual 'triple dip' La Niña from 2020 to 2023. Meanwhile, NOAA predicts another El Niño may form later this year, with potential effects on hurricanes and global heat levels.

NOAA's revised system now compares ocean temperatures in the tropical Pacific to the wider tropics rather than using fixed thresholds. This relative approach accounts for rising baseline temperatures caused by climate change. As a result, future El Niño events may appear less frequent, while La Niña conditions could be detected more often.

Between 2020 and 2023, the planet experienced three consecutive La Niña winters—a rare 'triple dip'—without an El Niño interruption. This prolonged cooling phase still contributed to rising global temperatures, puzzling researchers. Then, in early 2023, Earth's average monthly temperature surged and remained high through 2025.

A recent study linked around 75% of the planet's growing energy imbalance to two key factors: long-term human-driven warming and the shift from La Niña's cooling to El Niño's heat. NOAA's latest forecast suggests another El Niño could develop in late 2024, possibly weakening Atlantic hurricanes but pushing global temperatures even higher by 2027.

The new calculation method was introduced in August 2024. So far, no clear effects on weather classifications have been recorded for September and October of this year.

The updated NOAA system reflects how climate change is reshaping traditional weather patterns. With more La Niña events likely under the new criteria, future forecasts may look different. The next El Niño, if it arrives, could further amplify global warming trends in the coming years.