Climate change belief systems across political groups in the United States

General attitude. General attitude was measured with a question asking “On a scale from -3 (Very Bad) to +3 (Very Good) do you think global warming is a bad thing or a good thing?” with response options on a six-point scale: (1) “+3—very good,” (2) “+2,” (3) “+1,” (4) “-1,” (5) “-2,” and (6) “-3” (M = 4.63, SD = 1.31). US risk. US risk was measured with a question asking “How much do you think global warming will harm: people in the United States?” with response options on a four-point scale: (1) “Not at all,” (2) “Only a little,” (3) “A moderate amount,” and (4) “A great deal” (M = 2.66, SD = 1.05). Community risk. Community risk was measured with a question asking “How much do you think global warming will harm: Your community?” with response options on a four- point scale: (1) “Not at all,” (2) “Only a little,” (3) “A moderate amount,” and (4) “A great deal” (M = 2.42, SD = 1.02). Risk time. Risk time was measured with a question asking “When do you think global warming will start to harm people in the United States?” with response options on a six-point scale: (1) “Never,” (2) “In 100 years,” (3) “In 50 years,” (4) “In 25 years,” (5) “In 10 years,” (6) “They are being harmed now” (M = 3.91, SD = 1.93). Policy support rebate. Policy support rebate was measured with a question asking “How much do you support or oppose the following policies?: Provide tax rebates for people who Table 1. Questions and labels for questions included in the climate belief systems. Labels Types Questions GW happening Belief Do you believe global warming is happening (Rephrased)

GW human cause Belief Assuming global warming is happening, do you think it is a human cause? GW consensus Belief In your opinion, to what extent do scientists agree that global warming is happening (Rephrased) GW worry Other How worried are you about global warming? Collective efficacy Other How much do you think humans can reduce global warming? (Rephrased) General attitude Other Do you think global warming is a bad thing or a good thing? US risk Risk perception How much do you think global warming will harm people in the United States Community risk Risk perception How much do you think global warming will harm your community? Risk time Risk perception When do you think global warming will start to harm people in the United States? Policy support rebate Policy support How much do you support or oppose the following policies? Provide tax rebates for people who purchase energy-efficient vehicles or solar panels Policy support fund Policy support How much do you support or oppose the following policies? Fund more research into renewable energy sources, such as solar and wind power. Policy support CO2 Policy support How much do you support or oppose the following policies? Regulate carbon dioxide (the primary greenhouse gas) as a pollutant Political behavior Behavior Over the past 12 months, how many times have you done each of the following? Written letters, emailed, or phoned government officials about global warming Consumer behavior reward Behavior Over the past 12 months, how many times have you rewarded companies

that are taking steps to reduce global warming by buying their products? Consumer behavior punish Behavior Over the past 12 months, how many times have you punished companies that are opposing steps to reduce global warming by NOT buying their products? Note. GW = Global warming. Questions GW happening, GW consensus, and Collective efficacy are rephrased from the original survey questions in order to fit into the table. For the full text, see Measurements of Beliefs and Attitudes in the supplemental document. https://doi.org/10.1371/journal.pone.0300048.t001 PLOS ONE Climate change belief system PLOS ONE | https://doi.org/10.1371/journal.pone.0300048 March 20, 2024 5 / 16