This year, elections and extreme weather events have collided: In India, the spring general election was snarled by a heat wave that killed dozens of people, including poll workers. In Germany, severe flooding prompted evacuations just days before elections for the European Parliament. And in the US, people attending campaign rallies have fallen ill from record-breaking heat.
Political contests set the course for climate policy, as the race between Democrat Kamala Harris and Republican Donald Trump surely will. Yet it's unlikely that heat waves and disasters are changing the minds of enough voters who experience them to alter the results.
A growing body of research focuses on whether experiencing abnormal heat and other climate change-linked weather events shapes the way people vote, but a clear consensus hasn't emerged. If people are in fact casting ballots based on their experiences of disasters, it appears to be a small number of them.
In one recent study, voters in areas of Germany that experienced flooding in 2021 were not measurably more likely than those elsewhere in the country to cast their ballots for the environmentalist Green Party in that year's federal elections. While there was evidence of a small effect in some of the hardest-hit areas, direct exposure to the floods generally "had little to no effect", the researchers wrote.
Some political parties did appear to get a boost: those currently in power, which in the affected areas had committed to substantial relief efforts just before the election.
"People really seem to prefer immediate aid over some promise of, 'Okay, we're going to stop climate change for the next century,'" said Hanno Hilbig, the study's lead author and an assistant professor of political science at the University of California at Davis. Other research has found a clearer, though still moderate, effect. Across 22 countries in the Organization for Economic Co-operation and Development, people in areas with higher-than-normal average temperatures in the past year were more likely to say they supported left-leaning parties, and in particular ones with green policy agendas, according to a recent working paper. It was largely older people who shifted left.
People in areas of California affected by wildfires are more likely to vote for pro-environment ballot measures, another study observed. Republicans were more likely than Democrats to vote differently on environmental measures after wildfires.
Studies on the link between climate shocks and public opinion vary in the way they define weather events, how they measure opinion and more, a 2019 review of evidence on the subject noted. At the time, there was "modest support" for an association, but it was hard to interpret the available research, according to the authors.
The evidence that disasters have an effect has mounted since that review was published, in the view of Michael Coury, an applied microeconomist at the University at Buffalo and the author of the study on California. Researchers have used better statistical techniques and studied outcomes like vote counts, he said.
Still, the studies of wildfires and heat find shifts of just a few percentage points.
"There are many, many things that are going to impact an election, and this is just a small part of it," said Maria Cotofan, a lecturer in economics at King's College London and lead author on the paper about heat, which has not yet undergone peer review. Dr Cotofan still sees the results as meaningful in a world that's getting hotter -- and she noted that even the shift they observed could "make a huge difference" in a winner-takes-all race. None of this means voters are ignoring climate change writ large. In the US, nearly four in ten registered voters say global warming will be "very important" to their vote in this year's presidential election, according to a survey by climate communication research hubs at Yale University and George Mason University. An increase in concern about climate change from 2016 to 2020 was "likely" enough to decide the last presidential election in favour of Joe Biden, all else being equal, an analysis published in January found.
The fact that many people already have views on climate change may help explain why it's hard for a single disaster to move the needle, Asst Prof Hilbig said. What's more, the influence of any one disaster may have decreased as they've become more common in recent years, he said.
Yet, personal experience of climate change may have effects that election results don't capture. While voters tend to stick with a single party in the US, policies like the Inflation Reduction Act are more "politically palatable" when people care more about climate change, Asst Prof Coury said.
"I'm somewhat sceptical that maybe it changes the outcome of the election," he said, but the impact of disasters could lead to "both parties moving more towards a pro-environment direction". © 2024 Bloomberg
Matthew Griffin is Climate Reporter, Bloomberg News.