During a summer of scorching heat that has broken records and forced Americans to confront the reality of climate change, conservatives are laying the groundwork for future Republican administration that would dismantle efforts to slow global warming.

The move is part of a sweeping strategy dubbed Project 2025 that Paul Dans of the Heritage Foundation, the conservative think tank organizing the effort, has called a “battle plan” for the first 180 days of a future Republican presidency.

The climate and energy provisions would be among the most severe swings away from current federal policies.

The plan calls for shredding regulations to curb greenhouse gas pollution from cars, oil and gas wells and power plants, dismantling almost every clean energy program in the federal government and boosting the production of fossil fuels — the burning of which is the chief cause of planetary warming.

The New York Times asked the leading Republican presidential candidates whether they support the Project 2025 strategy but none of the campaigns responded. Still, several of the architects are veterans of the Trump administration, and their recommendations match positions held by former President Donald J. Trump, the current front-runner for the 2024 Republican nomination.

The $22 million project also includes personnel lists and a transition strategy in the event a Republican wins the 2024 election. The nearly 1,000-page plan, which would reshape the executive branch to place more power into the president’s hands, outlines changes for nearly every agency across the government.

The Heritage Foundation worked on the plan with dozens of conservative groups ranging from the Heartland Institute, which has denied climate science, to the Competitive Enterprise Institute, which says “climate change does not endanger the survival of civilization or the habitability of the planet.”

Mr. Dans said the Heritage Foundation delivered the blueprint to every Republican presidential hopeful. While polls have found that young Republicans are worried about global warming, Mr. Dans said the feedback he has received confirms the blueprint reflects where the majority of party leaders stand.

“We have gotten very good reception from this,” he said. “This is a plotting of points of where the conservative movement sits at this time.”

There is a pronounced partisan split in the country when it comes to climate change, surveys have shown. An NPR/PBS NewsHour/Marist poll conducted last month found that while 56 percent of respondents called climate change a major threat — including a majority of independents and nearly 90 percent of Democrats — about 70 percent of Republicans said global warming was either a minor threat or no threat at all.

Project 2025 does not offer any proposals for curbing the greenhouse gas emissions that are dangerously heating the planet and which scientists have said must be sharply and quickly reduced to avoid the most catastrophic impacts.

Asked what the country should do to combat climate change, Diana Furchtgott-Roth, director of the Heritage Foundation’s energy and climate center, said “I really hadn’t thought about it in those terms” and then offered that Americans should use more natural gas.

Natural gas produces half the carbon dioxide emissions of coal when burned. But gas facilities frequently leak methane, a greenhouse gas that is much more powerful than carbon dioxide in the short term and has emerged as a growing concern among climate scientists.

The blueprint said the next Republican president would help repeal the Inflation Reduction Act, the 2022 law that is offering $370 billion for wind, solar, nuclear, green hydrogen and electric vehicle technology, with most of the new investments taking place in Republican-led states.

The plan calls for shuttering a Department of Energy office that has $400 billion in loan authority to help emerging green technologies. It would make it more difficult for solar, wind and other renewable power — the fastest growing energy source in the United States — to be added to the grid. Climate change would no longer be considered an issue worthy of discussion on the National Security Council, and allied nations would be encouraged to buy and use more fossil fuels rather than renewable energy.

Erasing that finding, conservatives have long believed, would essentially strip the federal government of the right to regulate greenhouse gas emissions from most sources.

In interviews, Mr. Dans and three of the top authors of the report agreed that the climate is changing. But they insisted that scientists are debating the extent to which human activity is responsible.

On the contrary, the overwhelming majority of climate scientists around the world agree that the burning of oil, gas and coal since the Industrial Age has led to an increase of the average global temperature of 1.2 degrees Celsius, or 2.2 degrees Fahrenheit.

The plan calls on the government to stop trying to make automobiles more fuel efficient and to block states from adopting California’s stringent automobile pollution standards.

Ms. Furchtgott-Roth said any measures the United States would take to cut carbon would be undermined by rising emissions in countries like China, currently the planet’s biggest polluter. It would be impossible to convince China, to cut its emissions, she said.

Mandy Gunasekara was chief of staff at the E.P.A. during the Trump administration and considers herself the force behind Mr. Trump’s decision to withdraw the United States from the 2015 Paris climate accord. She led the section outlining plans for that agency, and said that regarding whether carbon emissions pose a danger to human health “there’s a misconception that any of the science is a settled issue.”

Bernard L. McNamee is a former Trump administration official who has worked as an adviser to fossil fuel companies as well as for the Texas Public Policy Foundation, which spreads misinformation about climate change. He wrote the section of the strategy covering the Department of Energy, which said the national laboratories have been too focused on climate change and renewable energy. In an interview, Mr. McNamee said he believes the role of the agency is to make sure energy is affordable and reliable.

Mr. Dans said a mandate of Project 2025 is to “investigate whether the dimensions of climate change exist and what can actually be done.” As for the influence of burning fossil fuels, he said, “I think the science is still out on that quite frankly.”

In actuality, it is not.

The top scientists in the United States concluded in an exhaustive study produced during the Trump administration that humans — the cars we drive, the power plants we operate, the forests we destroy — are to blame. “There is no convincing alternative explanation supported by the extent of the observational evidence,” scientists wrote.

Climate advocates said the Republican strategy would take the country in the wrong direction even as heat waves, drought and wildfires worsen because of emissions.

“This agenda would be laughable if the consequences of it weren’t so dire,” said Christy Goldfuss, chief policy impact officer for the Natural Resources Defense Council, an environmental group.

Republicans who have called for their party to accept climate change said they were disappointed by the blueprint and worried about the direction of the party.

“I think its out-of-touch Beltway silliness and it’s not meeting Americans where they are,” said Sarah Hunt, president of the Joseph Rainey Center for Public Policy, which works with Republican state officials on energy needs.

She called efforts to repeal the Inflation Reduction Act, which is pouring money and jobs overwhelmingly into red states, particularly impractical.

“Obviously as conservatives we’re concerned about fiscal responsibility, but if you look at what Republican voters think, a lot of Republicans in red states show strong support for provisions of the I.R.A.,” Ms. Hunt said.

Representative John Curtis, Republican of Utah, who launched a conservative climate caucus, called it “vital that Republicans engage in supporting good energy and climate policy.”

Without directly commenting on the G.O.P. blueprint, Mr. Curtis said “I look forward to seeing the solutions put forward by the various presidential candidates and hope there is a robust debate of ideas to ensure we have reliable, affordable and clean energy.”

Benji Backer, executive chairman and founder of the American Conservation Coalition, a group of young Republicans who want climate action, said he felt Project 2025 was wrongheaded.

“If they were smart about this issue they would have taken approach that said ‘the Biden administration has done things in a way they don’t agree with but here’s our vision’,” he said. “Instead they remove it from being a priority.”

He noted climate change is a real concern among young Republicans. By a nearly two-to-one margin, polls have found, Republicans aged 18 to 39 years old are more likely to agree that “human activity contributes a great deal to climate change,” and that the federal government has a role to play in curbing it.

Of Project 2025, he said, “This sort of approach on climate is not acceptable to the next generation.”