The conservative site Breitbart published a piece that strays so far from established climate science, one research scientist called it “quite possibly the worst ‘climate’-related article I’ve ever encountered.”

Breitbart’s latest piece of climate science denial — an article headlined “Scientists Prove Man-Made Global Warming Is a Hoax” — is so inaccurate and misleading that when the nonpartisan site Climate Feedback asked 10 climate scientists to comment on it, they got replies like “woefully ignorant,” “nonsensical,” and “a willful attempt to misguide their readership.”

Breitbart has an audience of more than 20 million visitors each month, according to one site that analyzes metrics, meaning its misleading claims have the potential to spread quickly. And in this case, the article was a bizarre rewrite of a recent ThinkProgress article on a major new study that actually shows human-caused global warming is more worrisome than previously thought, not less.

The study itself found that our current levels of atmospheric carbon dioxide, 410 parts per million (ppm), were last seen on Earth three million years ago — when temperatures were much higher, the great ice sheets were far smaller, and sea levels were some 65 feet higher.


But in Breitbart’s Orwellian reinterpretation, it writes: “ThinkProgress reports that scientists have finally proven that the theory of man-made Global Warming is a total hoax.”

Yet, Breitbart links to the study’s news release from the Potsdam Institute for Climate Impact Research, the first paragraph of which explicitly states, “today, it is the increase of greenhouse gases due to the burning of fossil fuels that is fundamentally changing our planet, the analysis further confirms.”

So how does Breitbart turn an analysis that confirms society’s burning of fossil fuels is causing climate change into one that somehow proves human-caused global warming is a hoax? By asserting that because slow changes in the Earth system caused high levels of CO2 in the past, fast changes caused by humans can’t be causing them now.

“Three million — million — years ago CO2 levels on Earth were the same as they are today, but there is one major difference between three million years ago and today,” the Breitbart piece states. “Three million years ago, we humans were not driving cars or eating the meat that requires cow farts; we weren’t barbecuing or refusing to recycle or building factories; there was no Industrial Age, no plastic, no air conditioning, no electricity, no lumber mills, no consumerism, no aerosols.”

As science has proven, that argument is nonsense, pure and simple. Numerous studies have shown how humans, not natural factors like changes in solar radiation and volcanoes, are the main driver of today’s rising global temperatures.

“The new research shows that a past high CO2 period had lots of global warming, just like we expect from today’s human-driven CO2 changes,” said Mark Richardson, a researcher at NASA’s Jet Propulsion Laboratory. “Breitbart’s argument is that since CO2 changed naturally before, we can’t change it now.”


Dr. Richardson then pointed out, “This is like saying that fires happened naturally before so there is no way any of us could cause a fire. It’s wrong.”

Ken Caldeira, a leading climatologist working at the Carnegie Institution for Science, makes a similar analogy. “By the reasoning of this article, if a rock rolled down a hill three million years ago, no human can be responsible for rolling a rock down a hill today.”

“The fallaciousness of this reasoning is astounding,” Caldeira added.

Breitbart did not respond to request for comment from ThinkProgress.

Finally, it’s safe to say that the scientists who authored the new study understand it better than Breitbart. So what do they say?

The research, which involved creating a model that explains the temperature and atmospheric variations over the past 3 million years, “gives us confidence in our general understanding of how the climate system works,” said co-author Andrey Ganopolski. The study “is confirming how outstandingly important changes in CO2 levels are for Earth’s climate.”


Lead author Matteo Willeit explained, “Our results imply a strong sensitivity of the Earth system to relatively small variations in atmospheric CO2. As fascinating as this is, it is also worrying.”

It’s worrying because an Earth strongly sensitive to small changes in CO2 will inevitably face the worst-case scenario when it comes to climate change impacts. So it’s doubly urgent that we reject the climate disinformation from conservative media outlets like Breitbart and cut CO2 as rapidly as possible.