Nearly 15% of Americans don’t believe climate change is real, a new study out of the University of Michigan reveals – shedding light on the highly polarized attitude toward global warming.
Additionally, denialism is highest in the central and southern US, with Republican voters found less likely to believe in climate science.
Using artificial intelligence, researchers analyzed over 7.4m tweets posted by roughly 1.3 million people on the social media platform X (previously Twitter) between 2017 and 2019. The social media posts were geocoded, and classified as “for” or “against” climate change using a large language model, a type of artificial intelligence developed by OpenAI.
“Over half of the tweets we looked at simply denied that climate change was real, that it was a hoax,” said Joshua Newell, co-author of the study and professor of environment and sustainability at the University of Michigan. “It wasn’t surprising but it was disappointing, I would hope that more and more Americans would believe in climate change and the importance of addressing it.”
Donald Trump emerged as one of the most influential figures among climate change deniers. His tweets around a cold snap in Texas in December 2017, as well as his missives rejecting the 2018 IPCC report released at the Cop24 UN conference, were some of his most engaged social media posts among climate change deniers.
“Public figures such as Trump are highly influential,” Newell said, “when they use these events to trigger disbelief in climate change among social media users.”
The findings are consistent with similar studies, such as the recent survey out of Yale University which estimates that as of 2023, 16% of Americans do not believe in climate change (about 49 million people).
Acceptance and belief in global warming is most prevalent along the west and east coasts, correlating with those regions’ high rates of Democratic voters. Still, clusters of denialism exist within blue states, like in the case of Shasta county, California. There, disbelief in climate change is as high as 52%, but statewide, less than 12% of California’s population does not believe in global warming.
“It comports with my understanding that there is a small but very vocal and active minority of the public that still denies the overwhelming evidence of human-caused warming,” said Michael Mann, climatologist and geophysicist at the University of Pennsylvania, about the study.
Last week, Mann was awarded $1m in a defamation lawsuit against conservative writers who called his pioneering climate change research “fraudulent”, comparing it to the work of a convicted child molester. In his book The New Climate War, Mann argues that scientists have to rebut the misinformation and disinformation promoted on social media by bad actors, “not because we’re going to win them over, their ideological heels are dug in, but because they are infecting the entire social media space with myths, falsehoods and toxic anti-scientific sentiment”, Mann said.
Researchers’ use of AI helped classify millions of social media posts that otherwise would be too time-consuming and expensive to conduct. Still, some skepticism remains regarding the ethics of using AI for research, as artificial intelligence has a documented history of bias, especially in facial recognition, highlighting the need for human vetting.
“It’s an intriguing new tool to use for these purposes,” Mann said. “But its limitations must be kept in mind as it’s an evolving technology.”
It is up to social media platforms to combat misinformation, and fact-check what the researchers call “knowledge vulnerability”.
“There is proper action by the social media companies to monitor disinformation and to act accordingly,” Newell said, referencing Trump’s ban from X (then Twitter) following the January 6 insurrection. “These very powerful social media companies should consider similar strategies for misinformation regarding climate change.”
