One by one, the tools available to President Biden to fight climate change are being stripped away.

After a Supreme Court decision on Thursday, the Environmental Protection Agency will have less authority to limit carbon dioxide from power plants, a major source in this country of the pollution that is dangerously heating the planet.

It’s one in a series of setbacks for Mr. Biden, who came into office with the most ambitious climate agenda of any president, pledging to the rest of the world that the United States, the world’s largest historic emitter of greenhouse gases, would cut that pollution in half by the end of the decade.

In a statement, Mr. Biden called the ruling “another devastating decision that aims to take our country backwards” and said the conservative majority on the court was siding “with special interests that have waged a long-term campaign to strip away our right to breathe clean air.”

“The science confirms what we all see with our own eyes — the wildfires, droughts, extreme heat, and intense storms are endangering our lives and livelihoods,” Mr. Biden said. “I will take action. My administration will continue using lawful executive authority, including the EPA’s legally-upheld authorities, to keep our air clean, protect public health, and tackle the climate crisis.”

Some experts say that after the Supreme Court’s decision in the case, West Virginia v. E.P.A., it will soon be mathematically impossible for Mr. Biden to meet his goals.

“At this point I don’t see any way to hit the kind of targets they laid out,” said David G. Victor, an expert in climate policy at the University of California, San Diego.

The consequences could be severe. Scientists say the United States must hit Mr. Biden’s target if it is to do its part to limit average global warming to 1.5 degrees Celsius, or 2.7 degrees Fahrenheit, compared with temperatures before the Industrial Revolution. That is the threshold beyond which the likelihood significantly increases of catastrophic impacts such as deadly heat waves, drought, wildfire and storms. The planet has already warmed an average of about 1.1 degrees Celsius.

But Mr. Biden has faced obstacle after obstacle in his push for climate action, ranging from conflicts within his own party to a worldwide energy crunch triggered by the war in Ukraine to well-funded legal challenges from Republicans and the fossil fuel industry.

Patrick Morrisey, the Republican attorney general of West Virginia and the lead plaintiff in the case, called the decision a “great win for West Virginia and her residents,” adding, “We are pleased this case returned the power to decide one of the major environmental issues of the day to the right place to decide it: the U.S. Congress, comprised of those elected by the people to serve the people.”

The problem for Mr. Biden is that Congress has so far failed to act on climate change. The centerpiece of the president’s climate plan, legislation to replace coal and gas-fired power plants with wind, solar and nuclear energy, was deleted from a major domestic policy bill last fall after objections from Senator Joe Manchin III, Democrat of West Virginia. Mr. Manchin, who has personal financial ties to the coal industry, has been able to single-handedly set the limits of Mr. Biden’s legislative ambitions as the key swing vote in an evenly divided Senate.

The domestic policy bill in limbo on Capitol Hill still includes what would be a historic increase in tax credits to spur the wind and solar industries. But it is unclear if Mr. Manchin will support the plan and the legislation could die if Republicans, who have shown little interest in climate action, retake one or both chambers in the midterm elections.

Mr. Biden has focused on the nation’s top source of greenhouse gas pollution — transportation — by directing the E.P.A. to craft tough new limits on tailpipe emissions to speed up adoption of electric vehicles. But those rules are already under legal assault in lower courts by many of the same plaintiffs who were victorious in this week’s Supreme Court case.

As a candidate, Mr. Biden promised to end drilling on public lands — oil, gas and coal extraction from federal land and waters generates 25 percent of the nation’s greenhouse gas emissions. But when he tried to pause new drilling, it was overturned by a legal challenge from Republican attorneys general from states that produce fossil fuels. The administration held its first onshore drilling lease sale this week in seven Western states.

“The judicial branch and the legislative branch are seriously hindering Joe Biden’s ability to get the job done on climate,” said Richard Lazarus, a professor of environmental law at Harvard, who served on Mr. Biden’s E.P.A. transition team. “A lot of the optimism that everyone had a year ago is being replaced by pessimism. They’re running out of options right now.”

The Biden administration contends that it remains possible for the United States to meet its climate targets, by cobbling together a mix of executive actions.

“Ambitious climate action presents a singular opportunity to ensure U.S. global competitiveness, create jobs, lower costs for families, and protect people’s health and well being, especially those who’ve long suffered the burden of inaction,” Michael S. Regan, the E.P.A. administrator, said in a statement. “E.P.A. will move forward with lawfully setting and implementing environmental standards that meet our obligation to protect all people and all communities from environmental harm.”

The Supreme Court ruling left intact the E.P.A.’s authority to regulate greenhouse gas emissions but blocked any attempt by the agency to write regulations so broad that they force the closure of coal-fired plants, which generate the most carbon dioxide, or compel utilities to switch from fossil fuels to wind, solar and other clean sources.

The E.P.A. still plans to issue tougher regulations to control methane, a potent greenhouse gas that leaks from oil and gas wells. And it plans stricter limits on other types of pollution generated by power plants, such as mercury, smog and soot. The idea is that cracking down on those pollutants could force electric utilities to clean up or shut down the dirtiest facilities, such as coal-burning power plants, which produce more carbon dioxide than gas-fired plants.

“Those air pollution rules will have co-benefits — as they are being enforced, they will squeeze out some CO2 pollution,” said Leah Stokes, a professor of environmental policy at the University of Santa Barbara, California, who has advised congressional Democrats on climate legislation. “It wouldn’t be the same amount. Every time we take a tool off the table we’re in a worse position.”

Meanwhile, the private sector has already been shifting away from fossil fuels and toward renewable energy sources.