Copernicus notes that while the new tropical-ocean warming index suggests the current event may not be stronger than past El Niños, September values indicate an exceptionally strong El Niño already, ahead of its anticipated peak later in the year.

The EU’s Copernicus Climate Change Service reports sea surface temperatures in the Nino3.4 region of the Pacific reached an all-time high of 29.70C in September, signaling exceptionally strong El Niño conditions.

This record surpasses temperatures seen in the 1982/1983, 1997/1998, and 2015/2016 strong El Niño events, underscoring the current event’s intensity, though Copernicus cautions it cannot definitively say it is the strongest ever based on their index.

Experts emphasize reducing fossil fuel emissions to shorten the duration of any overshoot and mitigate the warming impact associated with El Niño.

The broader climate context is that El Niño tends to increase drought and flood risks and amplify global warming effects, with scientists stressing the need to reduce fossil-fuel emissions to limit the duration of any overshoot of the 1.5C target.

Experts emphasize the need to reduce fossil fuel emissions to shorten the duration of any overshoot and bring temperatures down quickly.

September was 1.63C hotter than the pre-industrial baseline (1850-1900), underscoring ongoing climate change impacts as countries aim to keep warming within the Paris Agreement targets.

El Niño typically lasts 9 to 12 months and occurs every two to seven years, driving global weather changes through shifts in winds, pressure, and rainfall patterns.

The UN and climate authorities warn that strong El Niño is likely to push global temperatures toward new highs in 2027, and that overshoot of the 1.5°C target appears increasingly likely in the coming years.

Experts anticipate this El Niño could push global temperatures to new highs in 2027, even as the world remains above the 1.5°C threshold for an extended period.

UN warnings in September suggested the long-term 1.5°C target would be missed in the coming years, with El Niño likely extending overshoot into 2027 as temperatures stay elevated.

El Niño causes warming in the tropical Pacific, influencing global weather patterns, including droughts and floods, and interacts with ongoing global warming to amplify effects.