Hot topic: The impacts of El Niño in a warmer world

El Niño years tend to push global temperatures higher, not because they cause climate change, but because they amplify it

Staghorn coral in the Phi Phi Islands, in the Andaman Sea, Krabi, Thailand, showing early signs of coral bleaching as the tips turn white. El Niño can result in marine ecosystems altering as the base of the food chain changes. Coral reefs can bleach under enhanced thermal stress. Picture: iStock

The Pacific Ocean punches well above its weight in shaping global climate. Small changes in its temperature and winds can ripple outward, reshaping rainfall, intensifying extremes, and pushing global temperatures higher. This is the El Niño–Southern Oscillation (ENSO) in action and it’s a powerful climate cycle that flips between warm, cool, and neutral states. At the moment, it appears to be shifting again, and that shift matters.

The Pacific right now