1 Introduction

This report examines how climate denial has evolved on YouTube as scientific evidence for global warming has strengthened. Analysis of 12,058 climate-related videos from 96 channels between 2018 and 2023 shows that outright rejection of anthropogenic climate change has declined.

Across 4,458 hours of transcripts, the report identifies a shift towards narratives that undermine climate impacts, solutions, and climate science or advocates. These narratives aim to delay policy action by eroding trust in evidence-based climate responses.

3 Climate denialist claims can be categorised as old denial and new denial

The report uses five overarching “super-claims”. Old Denial comprises claims that global warming is not happening and that humans are not causing it. New Denial comprises claims that climate impacts are harmless, climate solutions will not work, and climate science or the climate movement is unreliable. These categories reflect the broad rhetorical strategies used by denialist channels.

4 Climate deniers are moving from the old denial of global warming and its causes to a new denial of climate impacts, solutions and the climate movement

The taxonomy highlights a move away from rejecting physical science towards attacking climate solutions and the credibility of climate researchers and advocates. Examples include claims that renewable energy is unworkable, that climate policies damage economies, and that experts exaggerate risks. The report notes that as observable climate impacts have become clearer, denialist narratives have adapted.

5 We used AI to analyse denialist claims in thousands of hours of YouTube content

The CARDS AI model was used to analyse one-minute transcript snippets from each video. CARDS classifies 17 sub-claims within the five super-claims. A 600-snippet validation test found the model to be 78% accurate when both researchers agreed with its categorisation.

In total, the AI identified 34,692 denialist claims. Videos containing these claims accumulated more than 325 million views, illustrating their broad reach.

6 YouTube data charts a clear shift from old denial to new denial

Old Denial represented 65% of denialist claims in 2018 but fell to 30% by 2023. Over the same period, New Denial rose from 35% to 70%. Growth was most pronounced in attacks on climate solutions and the reliability of climate science and advocacy.

7 New denial now constitutes 70% of climate denialist claims on YouTube

Between 2018 and 2023, claims that “climate solutions won’t work” increased by 21.4 percentage points. Claims that climate science or the climate movement is unreliable rose by 12 points. Claims that impacts are harmless increased by 1.6 points. The report attributes the shift to the reduced plausibility of denying physical warming as extreme weather and warming trends become more visible.

8 New denial: deniers have shifted to attacks on climate solutions and advocates

The fastest-growing sub-claims were that clean energy will not work, climate policies are harmful, climate science is unreliable, and climate advocacy is untrustworthy. Examples from channels such as PragerU, BlazeTV and the Heartland Institute illustrate how these claims are presented within broader critiques of environmental policy.

9 Old denial: deniers have shifted away from claims the climate is cooling

Claims that “the weather is too cold for global warming” fell by 19.9 percentage points. Claims that “we are heading into an ice age” dropped by 10.5 points, and claims that “ice is not melting” fell by 4 points. These declines reflect reduced emphasis on cold-weather narratives as warming evidence strengthens.

10 YouTube makes up to $13.4 million a year from channels posting denial

Based on Social Blade estimates, the 96 channels analysed may have generated up to USD 13.4 million in ad revenue in one year. YouTube’s current climate policy addresses Old Denial but does not cover New Denial, and the report documents ads running on both types of content.

11 Recommendations

The report recommends updating Google’s policy to reflect the scientific consensus on the causes, impacts and solutions to climate change. Digital platforms should demonetise and de-amplify climate denial to reduce financial incentives and limit reach. Climate advocates should adapt their strategies to counter the rise of New Denial and prioritise information integrity on digital platforms.