WASHINGTON — When John Barrasso, a Republican from oil and uranium-rich Wyoming who has spent years blocking climate change legislation introduced a bill this year to promote nuclear energy, he added a twist: a desire to tackle global warming.
Mr. Barrasso’s remarks — “If we are serious about climate change, we must be serious about expanding our use of nuclear energy” — were hardly a clarion call to action. Still they were highly unusual for the lawmaker who, despite decades of support for nuclear power and other policies that would reduce planet-warming emissions, has until recently avoided talking about them in the context of climate change.
The comments represent an important shift among Republicans in Congress. Driven by polls showing that voters in both parties — particularly younger Americans — are increasingly concerned about a warming planet, and prodded by the new Democratic majority in the House shining a spotlight on the issue, a growing number of Republicans are now openly discussing climate change and proposing what they call conservative solutions.
“Denying the basic existence of climate change is no longer a credible position,” said Whit Ayers, a Republican political consultant, pointing out the growing climate concern among millennials as well as centrist voters — two groups the G.O.P. will need in the future.
It is at least partly opportunism, given that some lawmakers are simply reframing longstanding policies or priorities as “climate” policy. Still it is a significant shift, indicating that at least a few prominent Republicans see an advantage to breaking from right-wing orthodoxy that has long dismissed or openly derided concerns about the climate.
In recent weeks Senator John Cornyn of Texas — an oil state where climate denial runs deep — said he is helping write legislation to reduce emissions through “energy innovation.” Senator Lamar Alexander of Tennessee said he wants to create a “Manhattan Project” for clean energy funding. Senator Lisa Murkowski of Alaska is exploring bipartisan plans to curb emissions from her position as chair of the Senate Committee on Energy and Natural Resources. And Representative Matthew Gaetz of Florida, who once called to abolish the Environmental Protection Agency, introduced legislation to tackle climate change by encouraging nuclear energy and hydropower, as well as “carbon capture” technology, which aims to pull planet-warming carbon dioxide out of the atmosphere.
There are subtler signs of this G.O.P. shift as well. When House Speaker Nancy Pelosi created the House Select Committee on the Climate Crisis this year, Republican leaders tapped Representative Garret Graves of Louisiana as the panel’s ranking member. Though he hails from a region dependent on oil and gas, Mr. Graves has struck a bipartisan tone and made a point of noting the deleterious effect sea level rise will have on his state’s economy.
But Republicans also are walking a tightrope. In the Trump administration, G.O.P. party orthodoxy has shifted strongly toward denying or dismissing the threat of climate change. Veering away from it could cause a lawmaker to lose campaign contributions and key political support.
“There’s a hesitancy I think on the part of Republicans to jump into a major policy without getting the cues from elites within the party and society as a whole that they’re going in the right direction,” said Steven Valk, a spokesman for Citizens’ Climate Lobby, which organizes to bring Republicans and Democrats together on market-based solutions to global warming.
In almost all of the cases in which conservative politicians are cautiously staking out territory on climate change, they still do not acknowledge the extent of man’s responsibility for causing it. Putting a price on emitting carbon into the atmosphere is verboten. And they insist solutions do not need to include eliminating or even curbing the use of oil, coal and other dirty energy sources primarily responsible for heating the planet.
“If we can find strategies that allow us to reduce emissions while continuing to use fossil fuels, I don’t think that’s necessarily a bad thing,” Mr. Graves said in a recent interview.
Likewise, Representative Frank Lucas of Oklahoma won praise when he took over as the new top Republican on the House Science Committee this year, and said that climate change has intensified droughts and storms. But in an interview Mr. Lucas also said reducing the use of coal, oil and gas is not a solution.
“I don’t believe that you create mandates for fossil fuels,” he said. “But if we work hard, we can create the alternatives that will cause the market to move toward them.”
And Mr. Barrasso, even as he promotes nuclear and other policies that he frames as climate friendly, characterizes Democrats as taking “drastic” positions. “What began as a conversation about cleaner energy, has transformed into punishing global agreements, and now full government economic takeover,” he said in a statement.
The result, political analysts said, is a fitful conservative effort. It is heavily reliant on funding for clean energy research and development, but could yet result in meaningful legislative action given the right political alchemy.
“I would say there’s an emerging consensus that the climate conversation this time around is real, and the interest of the public has caught up with the interest of the experts,” said Scott Segal, a fossil fuel lobbyist in Washington. “You never know how lightning will strike. There’s even a possibility that you can have action in a presidential year, though it’s not a particularly high percentage.”
On Thursday, Republican positions on climate change will face a test when the House votes on a measure to block President Trump from withdrawing the United States from the Paris climate agreement, the landmark 2015 pact among nations to cut global warming emissions. President Trump has said he is abandoning the accord.
In many ways the G.O.P.’s swing follows poll results. A record number of Americans now accept that climate change is real and a serious threat, though Republicans and Democrats still disagree on the cause. And a survey last year by Yale and George Mason universities of 1,067 registered voters found that majorities in both parties do agree that the government must address the problem.
Among Republicans, younger voters in particular are more likely to embrace climate action.
A new Pew Research Center poll found more than a third of Millennial Republicans agree that Earth is “warming mostly due to human activity,” compared with 18 percent of older Republicans. And nearly half of millennial Republicans say the government is not doing enough to “reduce the effects of climate change,” compared with 27 percent of older ones. (By contrast, 89 percent of Democrats say the government should do more).
The Green New Deal has played a role as well. The nonbinding congressional resolution calling for a 10-year mobilization to end fossil fuel use has unified Republicans against it. But the attention paid to it also has forced Republicans to offer their own solutions.
“You can’t beat something with nothing. And having a center right alternative to the Green New Deal makes sense,” said Mr. Ayers, the Republican political strategist.
Of course, climate denial is also alive and well among Republicans.
President Trump, who routinely mocks climate science, is preparing to announce a federal advisory panel to cast doubt on the overwhelming body of evidence that climate change is a threat. At a recent hearing at which former Secretary of State John Kerry testified on climate change, Representative Tom Massie, a Kentucky Republican, floated long-debunked theories that offer alternative explanations for warming other than human activity.
Democrats, for their part, said they are skeptical of new calls for compromise. Senator Edward J. Markey of Massachusetts, who sponsored the Green New Deal along with Representative Alexandria Ocasio-Cortez of New York, accused Republicans of rebranding “tired and inadequate proposals from the past” like nuclear and carbon-capture funding.
“We’ll know the Republicans are sincere when they step forward for permanent tax breaks for wind and solar and electric vehicles and battery technologies and clean building technologies. Because we can deploy those technologies right now. But they only continue to talk about research on technologies that will not be deployed for a decade,” Mr. Markey said.
Still, the handful of Republicans who have long looked for ways to tackle the rise of planet-warming emissions urged Democrats to seize the opportunity to find at least some common ground.
“Republicans who used to deny climate change as a real problem just to avoid the issue are now confronting it,” said Carlos Curbelo, a Republican carbon tax supporter who lost his Florida House seat last year. “It’s still early, but I think it’s important to recognize that clearly it’s now a debate about solutions.”
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