Posted on 29 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 the greenhouse effect still debated among climate scientists?

There has been broad agreement about the greenhouse effect for over a century.

In 1824, Joseph Fourier calculated that Earth ought to be much colder given its distance from the sun, and theorized that the atmosphere acts as a blanket, trapping heat and keeping the planet warmer than it would be otherwise.

Scientists later hypothesized that higher concentrations of greenhouse gases could raise temperatures. In 1896, Svante Arrhenius attempted to quantify this; his predictions remain on the high end of current climate models.

The basic science of the greenhouse effect is fairly simple: certain atmospheric gases such as carbon dioxide trap and redirect outgoing heat; some is radiated back downward, causing heat build up and temperatures to rise.

In 2021, the IPCC concluded it is unequivocal that human emission of greenhouse gases are the primary cause of modern 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

IPCC Sixth Assessment Report

Scientific American The Discovery of Global Warming

UCAR The History of Climate Science Research

NOAA How do we know the build-up of carbon dioxide in the atmosphere is caused by humans?

Environmental Research Letters Consensus on consensus: a synthesis of consensus estimates on human-caused global warming

The Conversation Lost in translation: confidence and certainty in climate science

EPA Causes of Climate Change

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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.