Table 1.

Summary of treatment content by wave with example headline

Condition	W2	W3
Science W2 → Science W3	Science predicts catastrophe from climate change	Science predicts catastrophe from climate change
	(e.g., “Climate change warning is dire”)	(e.g., “The clock is ticking to stop catastrophic global warming, top climate scientists say”)
Science W2 → Opinion W3	Science predicts catastrophe from climate change	Climate science can’t be trusted
	(e.g., “Climate change warning is dire”)	(e.g., “Climate change industry grows rich from hysteria”)
Science W2 → Placebo W3	Science predicts catastrophe from climate change	Unrelated articles
	(e.g., “Climate change warning is dire”)	(e.g., “Got a meeting? Take a walk”)
Science W2 → Partisan W3	Science predicts catastrophe from climate change	Democrats, Trump disagree over climate
	(e.g., “Climate change warning is dire”)	(e.g., “Trump steadily undoing US efforts on climate change”)
Placebo W2 → Science W3	Unrelated articles	Science predicts catastrophe from climate change
	(e.g., “Five sauces for the modern cook”)	(e.g., “The clock is ticking to stop catastrophic global warming, top climate scientists say”)
Partisan W2 → Partisan W3	Democrats, Trump disagree over climate	Democrats, Trump disagree over climate
	(e.g., “Poles apart on climate change in electionseason”	(e.g., “Trump steadily undoing US efforts on climatechange”)
Placebo W2 → Placebo W3	Unrelated articles	Unrelated articles
	(e.g., “Five sauces for the modern cook”)	(e.g., “Got a meeting? Take a walk”)

W2 and W3 indicate waves 2 and 3, respectively.