WASHINGTON — With the largest and most powerful tools that President Biden had hoped to use to fight climate change now stripped away, the White House is assembling smaller, less potent policies that could still help the nation reduce its planet-warming pollution, though not at the levels that Mr. Biden once promised.
The evident death in the Senate of Democrats’ climate change legislation, which was to have been the centerpiece of Mr. Biden’s plan to cut greenhouse gas emissions, comes just weeks after the Supreme Court handed down a decision that sharply limited the Environmental Protection Agency’s authority to regulate carbon dioxide emissions from power plants, the nation’s second-largest source of greenhouse gases.
Legal scholars say that the justices’ decision will, in turn, set a precedent that could limit the federal government’s authority to enact future climate regulations on other major sources of heat-trapping emissions, including cars and trucks.
Experts say that the gutting of those policies now makes it all but impossible for the United States to meet Mr. Biden’s target of cutting the nation’s emissions 50 percent from 2005 levels by 2030. That is the amount that scientists say the United States must reduce its emissions in order to do its part to avoid the most catastrophic near-term impacts of climate change.
Understand What Happened to Biden’s Domestic Agenda
‘Build Back Better.’ Before being elected president in 2020, Joseph R. Biden Jr. articulated his ambitious vision for his administration under the slogan “Build Back Better,” promising to invest in clean energy and to ensure that procurement spending went toward American-made products.
A two-part agenda. March and April 2021: President Biden unveiled two plans that together formed the core of his domestic agenda: the American Jobs Plan, focused on infrastructure, and the American Families Plan, which included a variety of social policy initiatives.
The Infrastructure Investment and Jobs Act. Nov. 15, 2021: President Biden signed a $1 trillion infrastructure bill into law, the result of months of negotiations. The president hailed the package, a pared-back version of what had been outlined in the American Jobs Plan, as evidence that U.S. lawmakers could still work across party lines.
And if the world’s largest economy fails to keep its word on reducing emissions, analysts say, it will lose any leverage to compel other nations to reduce theirs.
“Manchin’s decision and the Supreme Court decision smashed the building that the Biden administration was constructing to meet this very ambitious climate target,” said Michael Wara, a climate policy expert at Stanford University.
“And they’re left with just a few pieces and now they’re trying to put together a structure with these few, smaller, less coherent pieces,” Mr. Wara added. “It’s a lot harder. The 50 percent target was incredibly ambitious even with all the tools that Biden had. But with what they have left, they can still achieve a significant fraction of that.”
Here are a few of the ways that federal and state leaders might still reduce greenhouse gas emissions:
Regulate cars and trucks
Vehicles are the nation’s largest source of planet-warming pollution, and experts say that rapidly ending the use of gasoline-powered cars is crucial to avoiding the worst impacts of climate change. Mr. Biden has directed the Environmental Protection Agency and Transportation Department to write a transformative new regulation to rein in tailpipe pollution and accelerate the nation’s transition to electric vehicles.
In its most ambitious form, the new regulation, which would most likely not be completed until 2023 or 2024, would compel automakers to double down on selling enough electric vehicles to meet Mr. Biden’s target that half of all vehicles sold in the United States would be all-electric by 2030. But after the Supreme Court decision limiting the E.P.A’s authority to regulate greenhouse emissions, the agency may scale back its ambitions out of fear that such a bold new move could also be struck down by the courts.
Control pollution from power plants
Coal and gas-fired power plants are the nation’s second-largest source of greenhouse gas emissions. While the Environmental Protection Agency has been blocked by the Supreme Court from issuing a sweeping, ambitious rule that would shut down power plants fueled by coal and gas, the agency still plans to issue a more modest rule that would compel electric utilities to slightly lower their greenhouse emissions, and possibly to install technology to capture and sequester carbon dioxide pollution, although that pricey technology is not yet widely available.
The agency is also planning stricter limits on other types of pollution from power plants — like mercury, smog and soot — that are not greenhouse gases. 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.
Focus on methane
Carbon dioxide produced by burning fossil fuels is the planet’s most abundant and dangerous greenhouse gas, but methane, which is emitted into the atmosphere through leaks from oil and gas drilling sites, is a close second. It lingers in the atmosphere for a shorter period of time than carbon dioxide, but packs a bigger punch while it lasts. By some estimates, methane has 80 times the heat-trapping power of carbon dioxide in its first 20 years in the atmosphere.
In the coming months, the E.P.A. plans to issue tougher new regulations to curb leaks of methane from oil and gas wells, a move that could take a significant slice out of the nation’s overall greenhouse gas pollution. Legal experts say that, unlike the rules on power plants and autos, the methane rule has a good chance of withstanding legal challenges.
Rally action at the state level
Absent federal action on climate change, state-level climate policies will play a more important role. Just under half the states have already enacted significant climate policies. The leader is California, which in the coming weeks is expected to finalize a first-in-the-nation regulation requiring that all new cars sold in the state must be electric or zero-emission by 2035. Seventeen other states are in line to adopt the same rule when it passes in Sacramento.
California also requires that 100 percent of its electricity be generated from zero-carbon sources by 2045. Twenty-one other states have some version of that clean electricity standard, and several are advancing legislation for even more stringent versions.
Experts say that if enough states continue to move forward with aggressive carbon-cutting plans, it could help the United States lower its emissions, though not at levels close to what could be achieved by federal action.