Voting for pro-climate parties and candidates in response to extreme flooding experience

Søren Damsbo-Svendsen
University of Copenhagen
soerendamsbo.github.io

September 22, 2022

My project

• 3-year PhD project at Department of Political Science, University of Copenhagen (currently visiting Peter)
• Project about influence of extreme weather experience on climate attitudes and political behavior
• Personal experience as a source of information, media(ted) climate information as another, plus possible interactions
• Project has four papers (and a few side projects)

Four papers

1. Abnormally warm temperatures (also) make Europeans more climate-aware or pro-climate
2. Mass media climate coverage was the most plausible driver of the surge in attention to the climate issue in Europe around 2019
3. Poor Election Day weather depresses turnout, especially among “marginal voters” (e.g., young), but nice weather increases it
4. Working paper about flooding experience and pro-climate voting that I will present today

Working paper:
Voting for pro-climate parties and candidates in response to extreme flooding experience

Theory: extreme weather experience → behavior

RQ: How does climate-related extreme weather experience affect pro-climate voting?

• Ample evidence that extreme weather experiences affects climate change perceptions and attitudes
• But limited evidence that weather experiences affect actual behavior:
  • environmental behavior: it does not increase private energy saving, recycling, etc. (e.g. Rüttenauer 2021)
  • information/communication behavior: it can increase Twitter climate discussion, community dicussion, and web searches (e.g. Boudet et al. 2019; Osberghaus & Demski 2019; Sisco et al. 2017)
• How about more collective, political behavior?
  • Pro-climate voting!

Theory: extreme weather experience → behavior

RQ: How does climate-related extreme weather experience affect pro-climate voting?

Pro-climate voting:

• “a sizeable effect for pro-climate voting [20 %-points] after experiencing a flood” (Baccini & Leemann 2021)
• Californian wildfires increase support for costly, pro-environment policies by 5-6 %-points (Hazlett & Mildenberger 2020)
• Studies of retrospective voting and natural disasters sometimes show electoral rewards for (relatively) pro-climate parties (e.g. Gasper & Reeves 2011; Bechtel & Hainmueller 2011)
• Some null findings (e.g. Hilbig & Riaz, 2022; Melville-Rea 2022)

Severe northern European storm surge in December 2013

Northern Europe on
December 5 2013

European Environment Agency

Lynæs Bådelaug

rktic

Vikingeskibsmuseet

Jeanne & John Bollerup-Jensen

The 2013 storm surge in Denmark

• A rarely harmful and costly weather event → “Hurricane Sandy-equivalent”
• Data: detailed and complete geocoded storm surge insurance cases from the Danish Storm Council
• N = 2,924

Study I: how the vote share of pro-climate parties increases after the flood

Study I: voting for pro-climate parties

• Level of analysis: 1,386 polling districts

• Context: Danish parliamentary elections 1994-2019 (focus on 2011-2015)

• Outcome: district vote share for pro-climate parties

  • the left-green bloc w/ strong issue ownership

• Matched with district flooding based on 3 treatment definitions (all binary):

  • Storm surge damages (USD) above average
  • 1+ cases of rehousing cases
  • 1+ total flooding cases

• Difference-in-differences (DID) design

Study I: pretreatment balance

→ flooded and unflooded areas are fairly well-balanced on most covariates

Study I: parallel trends

→ generally, parallel pretrends (with some imbalances); 2015 (post) stands out!

Study I: DID results - main

→ flooding effect on pro-climate voting approx. 2-4 %-points

Study I: DID robustness - propensity-score matching

• Following Abadie (2005)
• Covariates: ln(polling district area), ln(distance to the water), ln(historical average turnout), academic education (%), primary education (%), ln(median income), ln(total wealth), single-family homes (%)
• DID estimate (damages): 2.06 (bootstrapped 95% CI: [1.11, 3.02])
• No placebo effects

→ flooding effect robust to covariate matching

Study I: DID results - flooding intensity

→ flooding effect tends to grow with flooding intensity

Study II: how voters reward pro-climate candidates with higher election chances after the flood

Study II: voting for pro-climate candidates

• Level of analysis: 9,554 election candidates

• Context: Danish local elections 2009-2017 (focus on 2013-2017)

• Outcome: elected or not (binary)

• Data: candidate survey w/ climate-related policy responses from 73% of candidates

• Pro-climate candidate (binary): climate as key priority or climate score above 4/5

• Treatment: high economic damage in municipality where candidate is running

• Triple differences (DIDID) design

Study II: pro-climate candidates

Key expectations

1. If voters engage in pro-climate voting,
2. the gap in election chances of pro-climate candidates versus non-climate candidates
3. should increase in heavily flooded communities (because of the flood)
4. → positive DIDID

Pro-climate candidates within each party (%)

Study II: DIDID results

• \(Treatment\:group \times Post\): electoral punishment of -4.0 pp for non-climate candidates because of the flood (small reward for pro-climate)
• \(Climate \:candidate \times Post\): no change over time (1 pp) in election chances of non-climate candidates in non-flooded areas
• \(Treatment\:group \times Climate \:candidate\): election chances of pro-climate candidates in flooded areas were only slightly higher before the flood (2.3 pp)

Study II: DIDID results

• DIDID, all parties: approx. 5.5 %-points

• DIDID, pro-climate parties: approx. 11.2 %-points

• → pro-climate candidates benefit electorally in post-flooding elections

Study II: DIDID placebo test

• Clear DIDID effects in real test (>1 rehousing cases)
• No DIDID effects in placebo test
• And also no DIDID for other candidate features: incumbent and pro-welfare

Conclusion

Conclusion 1/2

RQ: How does climate-related extreme weather experience affect pro-climate voting?

• Case: 2013 storm surge and surrounding Danish elections
• Detailed insurance data → local flooding exposure
• Twofold empirical study:

Conclusion 2/2

RQ: How does climate-related extreme weather experience affect pro-climate voting?

• Pro-climate parties (left-green bloc) gain at least 1.5 pp in flooded areas
• Pro-climate candidates see their election chances increase by 5.5 pp vs. non-climate candidates
• Extreme weather experiences can have significant, long-lasting effects on actual behavior → pro-climate voting
• Voters connect weather events to climate policy (at least implicitly) and make voting decisions on this basis

Thank you!

→ sdas@ifs.ku.dk

Marco Faria

Supplementary material

Environmental issue ownership

Study I: DID robustness - event study plots

→ some imbalances; 2011 appears to be the odd election

Study I: DID robustness - alternative baseline

→ with alternative baseline (2007) still flooding effect of at least 1.5 %-points