Fact brief – Is global warming just due to El Niño?
Posted on 8 July 2025 by Sue Bin Park
Skeptical Science is partnering with Gigafact to produce fact briefs — bite-sized fact checks of trending claims. You can submit claims you think need checking via the tipline.
Is global warming just due to El Niño?
El Niño Southern Oscillation is a short-term and cyclical weather phenomenon caused by alternating wind patterns that result in heat exchange between the ocean and the atmosphere; it cannot explain long-term warming.
El Niño originates when westward moving trade winds weaken, allowing warm surface waters to shift east across the tropical Pacific. This reverses the La Niña pattern, where trade winds push warm surface water toward Asia, upwelling cold water off the coast of South America.
During El Niño, heat is transferred from the ocean to the atmosphere, causing warming, while La Niña occurs when heat moves from the atmosphere to the ocean, causing cooling. Energy is moved around the climate system without adding any heat.
In contrast, climate science research indicates human-caused CO2 is the primary driver of today’s warming. Human activities that increase greenhouse concentrations in the atmosphere cause less heat to escape the atmosphere, resulting in additional and non-cyclical warming.
Go to full rebuttal on Skeptical Science or to the fact brief on Gigafact
This fact brief is responsive to quotes such as this one.
Sources
NOAA What is the El Niño–Southern Oscillation (ENSO) in a nutshell?
Journal of Geophysical Research Comment on “Influence of the Southern Oscillation on tropospheric temperature” by J. D. McLean, C. R. de Freitas, and R. M. Carter
About fact briefs published on Gigafact
Fact briefs are short, credibly sourced summaries that offer “yes/no” answers in response to claims found online. They rely on publicly available, often primary source data and documents. Fact briefs are created by contributors to Gigafact — a nonprofit project looking to expand participation in fact-checking and protect the democratic process. See all of our published fact briefs here.
