YouTube recommendation algorithm allegedly promoted climate misinformation

YouTube's recommendation system was alleged by the advocacy group Avaaz to promote climate denial and misinformation videos. The system's focus on engagement metrics reportedly created "rabbit holes" that led users toward inaccurate climate content.

YouTube · Incident Feb 1, 2019 · Indexed Jun 22, 2026 · 2 sources

The algorithm's focus on watch time and views allegedly drove users toward climate misinformation.
What
YouTube's recommendation system was alleged by the advocacy group Avaaz to promote climate denial and misinformation videos.
Incident date
Feb 1, 2019
Who
YouTube
Failure mode
Brand & Safety Incident
AI surface
Recommender
Severity
High

What happened

In 2019, it was alleged that YouTube's "up next" recommendation feature frequently suggested videos containing climate denialism and misinformation. An investigation by the advocacy group Avaaz found that the algorithm drove users toward content that contradicted scientific consensus on climate change. This pattern was attributed to the platform's emphasis on maximizing user watch time and engagement.

What broke inside the model

Failure path · mode profile · Brand & Safety Incident
  1. 01 · TriggerA user prompts the model in public view.
  2. 02 · Model stepThe model produces unsafe or off-brand output.
  3. 03 · Control gapNo filter holds the line before publish.
  4. 04 · FailureThe output goes public unchecked.
  5. 05 · ConsequenceA reputational or safety incident lands.

A contained signal crosses into output that goes public.

The recommendation engine's optimization for engagement metrics, specifically total watch time, inadvertently amplified sensationalist and controversial content. This created a feedback loop where the system prioritized high-engagement misinformation over factual scientific data to keep users on the platform.

Public visibilityHigh
Regulatory exposurePossible
Customer impactClass-wide
Financial impactUnknown
Time to disclosureMonths
  1. PressYouTube Has Been Promoting Climate Denialism Videostime.com
  2. PrimaryWhy is YouTube Broadcasting Climate Misinformation to...secure.avaaz.org
Permalinkhttps://failureindex.ai/failures/youtube-recommendation-algorithm-allegedly-promoted-cli
CitationAI Failure Index. "YouTube recommendation algorithm allegedly promoted climate misinformation" (FI-0595). Realm Labs. https://failureindex.ai/failures/youtube-recommendation-algorithm-allegedly-promoted-cli (indexed Jun 22, 2026).
Share cardA branded image of this record for posts and slides.

Data fields CC-BY 4.0, prose citation permitted. Incident ID FI-0595. Full dataset at /data.

Note from Realm Labs, the Index steward

How Realm would have caught this

Controls for this failure mode
  • Prism
  • OmniGuard
  • AI Detection & Response (AIDR)

Realm watches the model's internal state for the signature of unsafe or off-brand generation and can block or reroute the output before it becomes public, in real time rather than after it has been screenshotted.