Why El Niño releases ocean heat rather than creating new heat

El Niño years often bring record heat. That can make it sound as if El Niño creates heat. It does not.

Heat moves, it is not made. NOAA's Climate.gov explains that El Niño and La Niña do not add or remove energy from the climate system. Heat that is already there shifts between the deeper ocean and the atmosphere. In NOAA's words, "La Niña hides some of Earth's existing heat below the surface, while El Niño reveals it."

How it works. In La Niña, strong trade winds pile warm water into the western Pacific, storing heat at depth, while cooler water rises in the east. In El Niño the winds weaken, less cold water comes up and warm water spreads east. A huge area of ocean then gives off heat to the air, which warms the Pacific and then the global average (NOAA Climate.gov).

What we see in the record. NOAA notes that the warmest year of any decade is usually an El Niño year, and the coldest usually a La Niña year. In 2026, WMO reported that August was Earth's hottest August on record, with global sea surface temperatures at an all-time high.

And climate change? IMD says climate change does not cause El Niño, which is a natural cycle. But a warmer background means El Niño's heat comes on top of an already higher baseline, so its impacts, such as heatwaves, can be amplified.

Join the El Niño help room on soshyal.com to ask questions and share what you see in your area.