WASHINGTON — 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.
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 to meet that goal.
“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…