Nearly two thirds of Americans think global warming is affecting the weather.Credit: Scott Olson/Getty

The bulk of the economic burden resulting from climate change in the United States this century will fall on Republican strongholds where politicians have traditionally opposed policies to curb greenhouse gases. And as the impacts mount, they could potentially alter the political dynamics, says an analysis released on 29 January by the Brookings Institution, a think tank in Washington DC.

Researchers compared the projected economic impacts of global warming by the end of the century — including changes in mortality, agricultural yields and coastal damage driven by extreme weather and rising seas, for example — to recent voting patterns across the United States.

They found that vast swaths of the Republican-leaning southwest and southeast could see economic losses of 10–28% by the end of the century (see ‘Geography of impact’). Meanwhile, northern regions that include many Democratic-voting states, will experience fewer impacts and could even benefit from some of the results of climate change, including increases in agricultural yields.

Source: M. Muro et al. How the Geography of Climate Damage Could Make the Politics Less Polarizing (Brookings Institute, 2019); Data from S. Hsiang et al. Science 356, 1362–1369 (2017).

All told, 15 of the 16 states with the most to lose economically from global warming voted for Republican presidential candidate Donald Trump in 2016, according to the analysis (see ‘Voting climate’). Trump’s administration has worked aggressively to dismantle climate regulations put in place under former President Barack Obama.

Source: Brookings Institution

The US states at most risk are part of a “barricade” that opposes action to curb greenhouse-gas emissions, says co-author David Victor, a political scientist at the University of California, San Diego. “The politics are flipped upside down,” Victor says.

But, he adds, public recognition of the problem could increase as global-warming effects accumulate.

Facts to the rescue

There is some recent evidence that information about climate impacts is already persuading the public. In a poll conducted in December by the Yale Program on Climate Change Communication, 73% of US respondents said they understand that global warming is happening — an increase of ten percentage points since March 2015.

The number of people in the United States who say they have personally experienced the impacts of global warming has increased 15% over the same period, to 46%. And nearly two-thirds think that global warming is affecting the weather, while roughly half say that it made wildfires and/or hurricanes worse in 2018.

Climate change is not immune to the political divisions in the United States, but opinions do change in response to facts and personal experience, says co-author Mark Muro, a senior fellow at the institution. “That is what the new survey data is beginning to show.”

But translating public understanding of the influence of climate change into concrete — and potentially expensive — actions to curb greenhouse gases is a daunting challenge. Climate change remains a relatively low-priority issue among US voters, and the political leadership that is needed to build support for climate policies is missing, says Megan Mullin, a political scientist at Duke University in Durham, North Carolina.

“People elect leaders, but leaders also affect people’s perceptions,” Mullin says. As long as mainstream politicians refuse to acknowledge the scientific evidence on climate change, she says, making progress on meaningful climate policies will be difficult.

Still, Victor says that talking about economic impacts is more likely to persuade conservative voters of the need for action than is talking about environmental concerns. What’s needed, he says, is more scientific evidence that connects the dots between global warming and local costs to taxpayers.

“That’s what makes it all palpable,” he says. “Once you understand the local costs — that tells you what the public needs to do.”