Supplementary Material

Political orientation and climate concern shape visual attention to climate change

Jennifer C. Whitman1,2, Jiaying Zhao1.3, Kevin H. Roberts1, & Rebecca M. Todd1

1Department of Psychology, University of British Columbia2Department of Psychology, Northwestern University

3Institute for Resources, Environment and Sustainability, University of British Columbia

Corresponding Author. Please address all correspondence to Jennifer C. Whitman, PhD, Department of Psychology at Northwestern University, 102 Swift Hall, 2029 Sheridan Rd, Evanston IL USA, 60208-2710, e-mail: jennifer.whitman@northwestern.edu.

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List of Climate-Related Words Used as Targets: gasoline, oil, storm, extreme, resources,

hurricane, melting, global, flooding, CO2, carbon, warming, climate, drilling, habitats, ozone,

typhoon, drought, footprint, pollution, dioxide, wildfire, rainstorm, glacier, emissions, depletion,

hydrocarbon, earth.

List of Neutral Words Used as Targets: collection, equivalent, decorate, calculator, direction,

container, machinery, intuition, geography, bookshelf, shop, paint, download, optional, overalls,

tutelage, bottle, hammer, pencil, sleeve, mixing, kettle, packet, puddle, lower, cable, upper, lock.

Note. Each target word appeared twice in the full experiment, with the ordering of trials

randomized. This allowed for 56 trials from each word category.

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Supplemental Fig. S1. Histogram depicting how participants in Experiment 1 vary in the

magnitude of AB sparing at Lag 1. A positive value on the x-axis represents AB sparing for

Climate-Related words, while a negative value represents suppression of Climate-Related

information, relative to Neutral words.

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Supplementary Fig. S2. Scree Plot from Principal Component Analysis in Experiment 2

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Supplemental Fig. S3. Histogram depicting how participants in Experiment 2 vary in the

magnitude of AB sparing. A positive value on the x-axis represents AB sparing for Climate-

Related words, while a negative value represents suppression of Climate-Related information,

relative to Neutral words.

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Rationale for Samples Sizes and Analyses of Statistical Power in Experiments 1 and 2

In planning and running Experiment 1, we aimed to schedule N = 100 participants, based

on a rule of thumb, employed by social psychologists, that N = 80 participants is a bare minimum

for any correlational analysis of individual differences. N = 95 of our participants kept their

appointments and participated in the Experiment. We considered N = 500 to be a bare minimum

for identifying individual differences in a community sample, with wider variability in age,

education level, health, intelligence, visual acuity, and reading speed in a study with multiple

predictors. At the time of the study design, we had expected to identify multiple orthogonal

principal components each accounting for substantial portions of the variance in the survey data,

rather than the single dominant principal component identified in our results (see Fig. S2). These

general rules of thumb consider not only statistical power, discussed in more detail below, but

also the consideration that a sample should be large enough to have a reasonable chance of being

representative of the population about which inferences are made. Thus, our rules of thumb

prescribe larger samples for the more diverse populations in the general community.

Here, using G-Power software, we report a series of [post-hoc] power analyses to

examine the sample sizes we would need to detect different sizes of population effects at the p

< .05 level (two-tailed). This is in keeping with an approach suggested by O’Keefe (O'Keefe

2007). Detecting a population correlation of ρ = .10 would require a sample of at least N = 1293.

For a population correlation of ρ = .20, we would require a sample of at least N = 319; for a

population correlation of ρ = .30, a sample of at least N = 138; for a population correlation of ρ =

.40, a sample of at least N = 75; and, for a population correlation of ρ = .50 we would require a

sample of at least N = 46.

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Based on the observed correlation of r = .19 in Experiment 1, we conducted a power

analysis which suggested that a sample of N = 354 would be necessary to detect the effect in

Experiment 2 (assuming a population correlation of ρ = .19). This indicates that our sample of N

= 578 in Experiment 2 was adequate.

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Supplemental Table S1. Correlations between survey variables and AB sparing at Early Lags.

Criterion Variable from SurveyCorrelation

Coefficient r p-value

Human Caused (Supplemental Material Q 29) .030 .466

Climate Urgency (Supplemental Material Q 30) .012 .771

Climate Effects Vancouver Gen Area (Supplemental Material Q 33) .123** .003

Climate Effects Canada (Supplemental Material Q 34) .189** .000

Climate Effects Continent (Supplemental Material Q 35) .164** .000

Climate Effects World (Supplemental Material Q 36) .204** .000

Slope Climate Effects Geog. (slope from SM Q 33 to 36 above) .193** .000

Climate Effects 5years (Supplemental Material Q 37) .056 .179

Climate Effects 25years (Supplemental Material Q 38) .120** .004

Climate Effects 50years (Supplemental Material Q 39) .127** .002

Climate Effects 100years (Supplemental Material Q 40) .160** .000

Slope Climate Effects Time (calculated from above questions) .162** .000

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ABQ2 negative impact likelihood (end of AB Task in Cogent, Q 2) .074 .074

Age (Supplemental Material Q 2) .057 .170

Years Here (Supplemental Material Q 6) -.007 .863

Income (Supplemental Material Q 7) .052 .212

Income Percentile (calculated from above, Q 7) .079 .057

Schooling Level General (Supplemental Material Q 10) .066 .114

Schooling Level Math (Supplemental Material Q 11) -.011 .787

Longest Stay in One Town (Supplemental Material Q 13) .081 .052

Transit Frequency (transit never/rarely/sometimes/daily) -.030 .470

Bike Frequency (bike never/rarely/sometimes/daily) .090* .031

Child’s Age Category (<6, 6-10, 11-14, 15-17, 18+) .041 .328

Grandchild’s Age Category (<6, 6-10, 11-14, 15-17, 18+) -.037 .380

Subjective Independence (Supplemental Material Q 25) .047 .263

Anxiety General (Supplemental Material Q 26) .001 .989

Work Outdoors (Supplemental Material Q 20) .023 .587

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Subjective Climate Knowledge (Supplemental Material Q 27) .051 .219

Enviro Concern Friends & Family (Supplemental Material Q 31) .079 .058

Climate Concern Friends & Family (Supplemental Material Q 32) .097* .020

Environmental Concern (Supplemental Material Q 28) .115** .006

Political or Not (Supplemental Material Q 23) .052 .216

Political Debater (Supplemental Material Q 22) .068 .100

Politics Self Left vs. Right (Supplemental Material Q 41) -.014 .739

Politics Friends & Fam Left vs. Right (Supplemental Material Q 24) -.062 .138

BC Liberal (Supplemental Material Q 42) -.038 .363

BC NDP (Supplemental Material Q 43) .060 .149

BC Green (Supplemental Material Q 44) .073 .080

BC SoCred (Supplemental Material Q 45) -.046 .270

CDN Liberal (Supplemental Material Q 46) -.032 .436

CDN NDP (Supplemental Material Q 47) .047 .258

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CDN Green (Supplemental Material Q 48) -.045 .276

CDN Conservative (Supplemental Material Q 49) -.104* .012

Religious Y/N and Involvement (Supplemental Material Q 15a, 15c) .021 .608

* p < .05, uncorrected** p < .01, uncorrected

Note that the ‘Politics Self Left vs. Right (Supplemental Material Q 41)’ variable has lower variance, relative to support for the ‘CDN Conservative’ party, due to a programming error on the first version of the survey made in psychoPy, which made it necessary to exclude that question for N = 119 participants. These missing values were replaced by the mean from the remaining participants. Left vs. Right-wing political orientation did correlate strongly with several questions indexing environmental concern, as can be seen in the Supplementary spreadsheet CorrCoefoutputs for Supplemtary Materials.xlsx, posted on figshare at https://figshare.com/s/9ff3587724cb8faf799c

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List of key survey questions in Experiment 2

1. Please specify your gender (gender identity even if different from biological sex).

Male / Female / Other – please specify

2. Please specify your age.

3. What country do you live in?

Canada / Other – please specify

4. What city do you live in?

5. What languages can you speak fluently?

6. How long have you been in the Vancouver General Area?

I'm just visiting / I've lived here less than a month / I've lived here less than a

year / I've lived here more than a year / I've lived here more than 5 years / I've

lived here more than 10 years

7. What is your approximate annual income (before taxes)?

8. What is your current occupation?

9. Which of the following jobs or industries have you worked in?

retail / food service / tourism / forestry / mining / oil or natural gas / education /

health / transportation / shipping / film or animation / programming or IT / mid-

level management, general office admin or clerical / Other – please specify

10. What is the highest level of schooling you've completed?

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some highschool / completed highschool / 1 year post-secondary / 2 years post-

secondary / Bachelor's degree / Master's degree / [Ph.D./M.D./J.D./LL.D.]

11. What is the highest level of schooling you've completed in math or statistics?

grade 10 / grade 11 / grade 12 / 1st year college/university / 2nd year

college/university / 3rd year university / 4th year university / graduate school

course

12. Please list several cities/towns you've lived in that have had an effect on who you are

(minimum of one place).

13. What is the longest time you've spent living in one town or city?

less than 5 years / between 5 and 10 years / between 10 and 20 years / more than

20 years

14. Please list any terms you feel describe your nationality, heritage, and culture. Be

specific. Some examples include:

Chinese Canadian, family mostly from Canton province & Hong Kong

African American

Canadian, probably mostly European ancestors

half Scottish, half Japanese

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15. Do you have a religion?

Yes / No

[If yes] 15b. : What is your religion?

[If yes] 15c. How often do you participate in activities with your religious community,

such as going to a church/mosque/synagogue/temple?

not applicable - no religion / less than once a year / a few times a year / almost

every week / more than once a week

16. Do you have children?

Yes / No

[If yes] 16b. How old are your children?

17. Do you have grandchildren?

Yes / No

[If yes] 17b. Please specify the age of your youngest grandchild.

18. Do you own property?

Yes / No

[If yes] 18b. Please specify the location(s) of your property (or properties) by naming the

nearest intersection(s).

[coded for vertical distance from sea level. No street addresses recorded, in

order to protect confidentiality]

[If yes] 18c. Do you plan to sell your property soon?

never; it'll be inherited / probably someday / in the next few years / as soon as

possible

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19. Please list your favourite news sources (e.g. CNN, The Province, etc…).

20. Does your job require you to work outdoors?

never / rarely / sometimes / almost always

21. Are you Canadian, planning to become Canadian, or planning to live a long time in

Canada?

Yes / No

22. Do you enjoy debating political issues?

not at all, never / somewhat, sometimes / yes, very much

Likert Scale Questions

23. Are you interested in politics?

not at all:

I don’t care

not very

interested

somewhat

interested

very

interested

extremely

interested

24. Politically, would you describe your close friends and family as

very

left-wing

on average

somewhat

left-wing

on average

evenly

mixed

somewhat

right-wing

on average

very

right-wing

on average

25. Do you consider yourself an independent thinker?

strongly

disagree

disagree maybe agree strongly

agree

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26. Do you tend to be an anxious person?

strongly

disagree

disagree maybe agree strongly

agree

27. How well-informed are you about climate change?

I know almost

nothing about

it

I know a little bit

about it

I’m somewhat

well-informed

I’m very well-

informed

I’m an expert

28. How concerned are you about the environment in general?

not at all

concerned

a tiny bit

concerned

somewhat

concerned

very concerned extremely

concerned

29. Do believe that the climate is being changed by human activity (i.e. carbon emissions)?

impossible very

unlikely

unlikely maybe likely very

likely

certain

30. Do you think climate change will get harder to prevent or slow down the longer we wait

to deal with it?

strongly

disagree

disagree don’t know agree strongly

agree

31. How concerned are your close friends and family about the environment in general?

not at all

concerned

a tiny bit

concerned

somewhat

concerned

very concerned extremely

concerned

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32. How concerned are your close friends and family about climate change?

not at all

concerned

a tiny bit

concerned

somewhat

concerned

very concerned extremely

concerned

33. How likely is it that people in the Vancouver General Area and Fraser Valley will be

negatively affected by climate change?

impossible very

unlikely

unlikely maybe likely very

likely

certain

34. How likely is it that people in Canada will be negatively affected by climate change?

impossible very

unlikely

unlikely maybe likely very

likely

certain

35. How likely is it that people on this continent will be negatively affected by climate

change?

impossible very

unlikely

unlikely maybe likely very

likely

certain

36. How likely is it that people anywhere in the world will be negatively affected by climate

change?

impossible very

unlikely

unlikely maybe likely very

likely

certain

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37. How likely is it that people will be negatively affected by climate change in the next 5

years?

impossible very

unlikely

unlikely maybe likely very

likely

certain

38. How likely is it that people will be negatively affected by climate change in the next 25

years?

impossible very

unlikely

unlikely maybe likely very

likely

certain

39. How likely is it that people will be negatively affected by climate change in the next 50

years?

impossible very

unlikely

unlikely maybe likely very

likely

certain

40. How likely is it that people will be negatively affected by climate change in the next 100

years?

impossible very

unlikely

unlikely maybe likely very

likely

certain

41. Politically, would you describe yourself as left-wing or right-wing?

far left socialist New

Democratic

Party of

Canada

Liberal

Party of

Canada

Conservative

Party of

Canada

USA

Tea

Party

far right

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If you didn't have to choose only one party to vote for in BC PROVINCIAL elections, and

instead you could support and rate several parties at once, how would you rate each of these

parties?"

42. Liberal Party of BC

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

43. New Democratic Party of BC

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

44. Green Party of BC

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

45. Social Credit Party (formerly) of BC

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

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If you didn't have to choose only one party to vote for in CANADIAN FEDERAL elections,

and instead you could support and rate several parties at once, how would you rate each of

these parties?"

46. Liberal Party of Canada

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

47. New Democratic Party of Canada

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

48. Green Party of Canada

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

49. Conservative Party of Canada

strongly

oppose

mildly oppose neutral mildly

support

strongly

support

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Questions with Check-box Options

50. Have you been personally affected by a natural disaster (e.g. forest fire, mud/land slide,

flood, storm surge)?

Yes / No

[If yes] 36b. Which natural disaster(s) have personally affected you? Please check all

that apply.

forest fire / mud slide / land slide / river flood / ocean flood, e.g. storm surge

51. Have any of your close friends or family members been affected by a natural disaster

(e.g. forest fire, mud/land slide, flood, storm surge)?

Yes / No

[If yes] 37b. Which natural disaster(s) have affected your close friends or family

members? Please check all that apply.

forest fire / mud slide / land slide / river flood / ocean flood, e.g. storm surge

52. Have any members of your community been affected by a natural disaster (eg.. forest

fire, mud/land slide, flood, storm surge)?

Yes / No

[If yes] 38b. Which natural disaster(s) have affected your community? Please check all

that apply.

forest fire / mud slide / land slide / river flood / ocean flood, e.g. storm surge

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References

O'Keefe DJ (2007) Brief report: post hoc power, observed power, a priori power, retrospective

power, prospective power, achieved power: sorting out appropriate uses of statistical

power analyses. Communication methods and measures 1:291-299

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