Garret Graves is a forty-seven-year-old Republican congressman from Louisiana who, earlier this year, bet his considerable political future on the proposition that the age of conservative climate denial is over. Graves had come to the point of view, he told me recently, “that those who were denying were taking an unsustainable position. That the science was going to further and further sink the island that they were standing on, and that eventually they would be inundated.” When the Speaker of the House, Nancy Pelosi, announced a new Select Committee on the Climate Crisis this winter, after teen-age activists staged a sit-in at her office, Graves visited the Republican leader in the House, Kevin McCarthy, to argue that the new committee gave Republicans a chance to take a less obstinate position on climate change, if they were nimble enough to see it.

Graves, who is medium height and athletic, with a strong chin and a loud voice, came with a PowerPoint presentation, laying out for McCarthy “everything from the disasters to our progress on emissions, without blowing up the economy, to the strategic resources of the United States and those of other countries.” There was, he argued to McCarthy, “a better way to apply Republican principles to this issue of climate change”—an insistence that the challenge of climate change can be met by scientific innovation, by the application of our remarkable instruments and brains. In February, McCarthy named Graves to serve as the ranking member on the committee. And, just like that, the Republicans chose as their spokesman on climate change a gregarious, outdoorsy young man who liked to say that not only was sea-level rise real but that he had measured it with his own yardstick.

Environmentalists regarded this mainly as a stunt. Republicans had correctly interpreted the polling on climate change to mean that they had to change their public image on the issue. But they were not willing to break with the energy industry. Graves seemed sincere enough when he acknowledged a human role in changing the climate, but that hardly made him green. Graves’s lifetime rating from the League of Conservation Voters was just three per cent; in the last election cycle, he received almost twice as many campaign contributions from the oil-and-gas industry as from any other industry. “I’d love to see more Republicans get on board with climate action, but it’s not enough to change how they talk about this issue. They need to change how they vote,” Representative Kathy Castor, the Florida Democrat who chairs the Climate Crisis Committee, told me.

In the months since Republicans lost control of the House of Representatives in the midterm elections, there have been signs of a shift in their view of the environmental crisis, changes which may turn out to be meaningful, or may prove to be as ephemeral as a branding campaign.

In May, Senator John Cornyn, a powerful Texas conservative, announced “a growing consensus [that] the days of ignoring this issue are over.” The Republican pollster Frank Luntz then circulated a memo insisting that voters “believe the U.S. must change direction on climate policy.” Democrats and climate activists received these statements with some cynicism, because of Cornyn’s long-standing ties to the oil-and-gas industry, and Luntz’s infamous memo to George W. Bush, in 2002, advising the President that there was “still a window of opportunity to challenge the science” of climate change. It was hard to believe that the Republicans had found a new church if Luntz and Cornyn were still at the pulpit.

But it was tempting to think that if there was to be a genuine Republican conversion, it would come from someone like Graves. Before he was elected to office, Graves had made his name by leading the recovery and rebuilding work in Louisiana after Hurricane Katrina. He had led the state’s efforts to recover billions of dollars from BP after the Deepwater Horizon oil spill. His view, which he made clear to Castor, was that the parties should be able to agree immediately on projects that would help local communities adapt to and prepare for changes in the environment. Graves told me, “There is built up momentum in the atmosphere right now where adaptation is the thing you’ve got to do no matter what, right out of the gate.”

Earlier this summer, before Hurricane Barry had crashed into New Orleans but with the Mississippi swollen to a degree that made everyone nervous, I went to Baton Rouge to spend a day with Graves. A day earlier, there had been a tremendous storm: eight inches of water had poured onto the city’s downtown in eight hours. The state has not so much encountered the reality of the changing climate as been inundated by it. Storms have so constantly battered the Louisiana coast during the past decade that historical benchmarks have lost their meaning. As Graves put it to me, “We had a thousand-year flood in August of 2016. In March of that year, we had a five-hundred-year flood. One state over, in Texas, they had a thousand-year flood—Harvey. All of a sudden, you’re, like, I’m in my forties. Something’s wrong with the statistics.”

If Louisianans were beginning to see why there was always so much water everywhere, then Graves had done his part to coax that understanding along. Having spent his twenties as a staffer in Washington, he moved back to his home town of Baton Rouge in the months after Hurricane Katrina, to help work on the disaster’s aftermath for Governor Bobby Jindal. By 2008, Jindal had appointed Graves to lead the new Coastal Protection and Restoration Authority, whose mandate was to coördinate the environmental response to coastal erosion. In Louisiana, where a football field of land is lost to the sea every ninety minutes, the scale of that work is heroic. At the Center for River Studies, a state-funded research and public-education initiative in Baton Rouge, Graves showed me a wall-size map of Louisiana, with the many spots where land was being lost glowing red and the few where it was being replenished lit up in green. Graves pointed out the barrier islands he had helped to rebuild, the few places where engineers had helped resist a saltwater intrusion. Such projects cost hundreds of millions of dollars, required incredible ingenuity, and succeeded only in keeping tiny dots on the map from turning red.

It had taken a while after Katrina, as Graves explained over breakfast, for him to realize the extent of the permanent changes to Louisiana’s coast, but, in 2011, when he and his staff were revising the state’s coastal master plan, he started to see it clearly. One partial tally of projects reached two hundred and fifty billion dollars. “We were never going to get two hundred and fifty billion dollars,” Graves said. The agency changed its approach. The coastal master plan eventually included a line that ran across Louisiana, indicating which communities would be protected from the rising seas. North of the line was safe. South of it, Graves recalled, “We said, ‘Look, we don’t have the resources or the technical expertise to protect you.’ It was the first time we had told them the truth.” The reaction, in the small, conservative communities along the coast, was often furious. Graves said he got death threats. He and his staff held town halls on the coast, where, he recalled, “We would explain to people, ‘You don’t deserve this. This is unjust. But this is how we got here.’ ”