El Niño is a climate phenomenon in which sea-surface temperatures in the central and eastern equatorial Pacific Ocean become warmer than usual, influencing atmospheric circulation and weather patterns around the world.
El Niño is part of the El Niño–Southern Oscillation (ENSO) climate pattern. It typically develops when changes in ocean temperatures and atmospheric conditions weaken the usual easterly trade winds, allowing warm surface water to extend farther east across the tropical Pacific.
El Niño can affect rainfall, temperature, drought, flooding, and storm patterns in different regions. Its effects vary by location and season. Some places may experience unusually dry conditions, while others may experience heavier rainfall. It can also contribute to higher global average temperatures temporarily, particularly when it coincides with the long-term warming caused by greenhouse gas emissions.
El Niño is not the same as global warming or climate change. It is a naturally occurring climate phenomenon that can influence weather and temporarily affect global temperatures within a warming climate.
QUICK FACT
- El Niño and La Niña are opposite phases of ENSO, although their effects are not always exact opposites.
- El Niño can influence weather far beyond the Pacific Ocean through changes in atmospheric circulation.
- El Niño does not cause the same weather conditions everywhere. Its effects depend on the region, season, and other climate influences.
COMMONLY CONFUSED WITH
- El Niño–Southern Oscillation (ENSO): The broader climate system that includes El Niño, La Niña, and ENSO-neutral conditions.
- Global warming: The long-term rise in Earth’s average surface temperature, primarily driven by human activities that increase greenhouse gas concentrations.
- La Niña: An ENSO phase characterized by unusually cool sea-surface temperatures in the central and eastern equatorial Pacific.
SEE ALSO