An analysis of thousands of YouTube videos posted over the last five years finds a decline in videos that outright deny climate change but an uptick in those that impugn the credibility of scientists or question the practicality of shifting to renewable energy,

“Scientists have won the battle to inform the public about climate change and its causes, which is why those opposed to climate action have cynically switched focus to undermining confidence in solutions and in science itself,” said Imran Ahmed, head of the London-based Center for Countering Digital Hate, which undertook the research.

For the analysis, researchers used artificial intelligence to analyze transcripts of 12,058 videos, shared between 2018 and 2023, from the YouTube channels of climate contrarians. Nearly half of videos posted in 2018 denied the planet was warming at all. By 2023, that number had fallen to just 14 percent. Videos denying humans are the cause of climate change also dropped, but just slightly.

At the same time, the share of videos that exaggerated the costs or potential harms of efforts to move away from fossil fuels rose from 9 percent to 30 percent, while the share of videos arguing that scientists and advocates cannot be trusted grew from 23 to 35 percent. The portion of videos that cast doubt on the severity of climate change also grew slightly.

It is the policy of Google, which owns YouTube, not to run ads on videos that deny human-caused climate change, meaning creators cannot earn money from these videos. But ads, including from brand-name companies such as Hilton and nonprofits such as Save the Children, do run alongside videos that downplay the impact of climate change or make misleading claims about climate policy or renewable energy.

The Center for Countering Digital Hate is calling on Google to update its policy such that it will not run ads on videos that contradict the scientific consensus on the “causes, impacts, and solutions” to climate change. Said Ahmed, “They should refuse to amplify or monetize cynical climate-denial content that undermines faith in our collective capacity to solve humanity’s most pressing challenge.”

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