Science

California communities are banning syringe programs. Now the state is fighting back in court

Published

10 months ago

March 19, 2024

California communities are banning syringe programs. Now the state is fighting back in court

As Indiana officials struggled to contain an outbreak of HIV among people who injected drugs, then-Gov. Mike Pence reluctantly followed the urgings of public health officials and cleared the way for an overwhelmed county to hand out clean syringes.

Pence was far from enthusiastic about launching the program in Scott County, but after it rolled out in 2015, the percentage of injection drug users there who said they shared needles dropped from 74% to 22%. Within a few years, the number of new HIV infections plummeted by 96% and new cases of hepatitis C fell by 76%.

The Sierra Harm Reduction Coalition wanted to keep those same diseases in check in California. The tiny nonprofit got approval from the state to deliver syringes in El Dorado County to prevent the spread of life-threatening illnesses.

Yet when the program was discussed at a December meeting of the county’s Board of Supervisors, the success story in Indiana held little sway. Faced with complaints about discarded needles and overdose deaths, the supervisors voted to prohibit syringe programs in the county’s unincorporated areas.

“These programs may work in other parts of California and throughout the United States, although I have my doubts,” Sheriff Jeff Leikauf said at the meeting. “El Dorado County does not want or need these types of programs.”

El Dorado is among a growing number of California communities that have banned syringe programs, testing the state’s power and political will to defend them as a public health strategy. It is part of a broader pushback against “harm reduction” — the practical philosophy of trying to reduce the negative effects of drug use — as overdose deaths have soared.

Now California is fighting back. In a recently filed lawsuit, the Department of Public Health argued that local ordinances prohibiting syringe programs in El Dorado County were preempted by state law, making them unenforceable.

The state is seeking a court order telling El Dorado County and the city of Placerville, its county seat, to stop enforcing their bans and allow syringe programs to resume.

An El Dorado County spokesperson said Monday that the county does not comment on pending legal issues. Its district attorney, however, said he was outraged to learn of the lawsuit, saying that state leaders were “seeking to impose the normalization of hardcore drug use.”

“Don’t come into our county and double down on your failed policy,” El Dorado County Dist. Atty. Vern Pierson said in a statement. “Allowing addicts to use fentanyl and other hardcore drugs is exactly what has caused other California counties to experience a death rate that is out of control and getting worse.”

Mona Ebrahimi, the city attorney for Placerville, said the city had put a 45-day temporary moratorium in place “to study the ongoing effects of syringe service programs in the city.”

“The city wants to protect the health, safety and welfare of its residents,” Ebrahimi said.

The California Department of Public Health has long endorsed handing out sterile syringes as a proven way to prevent dangerous infections from running rampant when people share contaminated syringes. Researchers have linked syringe programs with a roughly 50% reduction in HIV and hepatitis C.

“It sounds crazy: ‘Wait, you want to give out the tools to people to do this thing that we all agree is a bad idea?’” said Peter Davidson, a medical sociologist at UC San Diego. But it works, said Davidson, who called the programs “probably the best studied public health intervention of the last 70 years.”

Public health officials also see them as a crucial way to reach people who use drugs and link them to addiction and overdose-prevention services. In Seattle, for instance, researchers found that injection drug users who started going to a needle exchange were five times more likely to enter drug treatment than those who never went.

Signs direct visitors to the syringe-exchange program at the Austin Community Outreach Center in Austin, Ind., in 2015. The program was set up to curb an outbreak of HIV among people who injected drugs.

(Darron Cummings / Associated Press)

And in California, harm reduction groups have been particularly effective in getting Narcan — a nasal spray that can reverse opioid overdoses — into the hands of people who need it.

It’s “hugely important to reduce overdose in the community, and these are the programs that do that,” said Barrot Lambdin, a health policy fellow at RTI International who studies the implementation of health interventions.

Yet leaders in some cities and counties have strenuously rejected the health benefits of syringe programs.

In El Dorado County, local leaders asserted that the efforts of the Sierra Harm Reduction Coalition had not “meaningfully reduced” HIV or hepatitis C cases since its syringe program began four years ago and said the free needles were ramping up the risk of deadly overdoses, which they argued were a bigger threat.

Street scene shows trees with fall colors, cars and old buildings

Alessandra Ross, a harm reduction expert at the California Department of Public Health, disputed such arguments in a letter to county officials. Ross pointed out that in just one year, the coalition handed out more than 2,200 doses of medication to reverse opioid overdoses, saving at least 421 lives. Without the group’s efforts, she wrote, “El Dorado County could have potentially lost more than ten times as many people to overdose.”

Under state law, the California Department of Public Health has the authority to approve syringe programs anywhere that deadly or disabling infections might spread through used needles, “notwithstanding any other law” that might say otherwise.

The agency argued that the “significant state and public interest in curtailing the spread of HIV, hepatitis, and other bloodborne infections extends to every jurisdiction in the state, especially since Californians travel freely throughout the state.”

After El Dorado County prohibited syringe services in unincorporated areas, the state public health department adjusted its authorization for the Sierra Harm Reduction Coalition program, limiting its operations to Placerville. In the court filing, the agency said it made the change out of concern for the coalition’s staff and volunteers, who could be at risk of arrest if they provided syringes in the unincorporated areas.

The nonprofit said when it stopped providing syringes outside of Placerville city limits, roughly 40% of its clients were cut off. In February, Placerville city officials passed their own urgency ordinance banning syringe programs for 45 days, exempting needle provision at health facilities.

Ebrahimi, its city attorney, said officials took that step “after CDPH concentrated their use by authorizing them only in Placerville and nowhere else in the county.”

The Sierra Harm Reduction Coalition stopped providing syringes in Placerville as well, according to the state lawsuit. The coalition did not respond Monday to requests for comment on the suit.

El Dorado County and Placerville are not alone: A wave of local bans went into effect last year in Placer County after a harm reduction group from Sacramento sought state approval to hand out clean syringes. The county’s sheriff and its probation chief said in a letter to the state that the syringe program proposed by Safer Alternatives thru Networking and Education, or SANE, would “promote the use of addicting drugs” and lead to more “dirty needles discarded recklessly in our parks.”

The Placer County Board of Supervisors voted unanimously to ban syringe programs in its unincorporated areas. Cities including Auburn, Loomis and Rocklin banned them too.

“We are the ones who should make these kinds of decisions,” then-Mayor Alice Dowdin Calvillo said at a September meeting of the Auburn City Council, “and not allow the state to just bully us.”

Public health researchers stress that studies have found that free needle programs do not increase crime or drug use, or worsen syringe litter. Yet as much of Placer County became a no-go zone, SANE withdrew its application for a syringe program there.

“Our political processes are not well set up for us to make reasoned, scientifically sound judgments about public health,” said Ricky Bluthenthal, a USC sociologist whose research has documented the effectiveness of syringe programs. It doesn’t help that “the populations at risk are often marginalized or not politically active.”

Our political processes are not well set up for us to make reasoned, scientifically sound judgments about public health.

— Ricky Bluthenthal, a USC sociologist who studies syringe programs

The California Department of Public Health declined to address whether it planned to challenge local bans on syringe programs elsewhere in the state, saying it “cannot comment on active litigation strategy.”

Syringe programs have long faced public skepticism: In a 2017 survey, only 39% of U.S. adults said they supported legalizing them in their communities.

Experts say the programs have faced increasing jeopardy as public concern wanes about the threat of HIV and frustration swells over other problems like soaring numbers of overdose deaths and the spread of homeless encampments. Even in Indiana’s Scott County, local leaders voted three years ago to shutter its needle exchange.

Clashes are also arising because programs are making moves into new parts of California, bolstered in some cases by state funding. California officials also have taken steps to help syringe programs overcome local opposition, including exempting them from review under the California Environmental Quality Act.

“It’s not surprising that cities and counties are motivated to protect the public health and safety of their residents through whatever tools they have at their disposal,” said attorney David J. Terrazas, who represented a group that successfully sued to overturn state approval of a syringe program in Santa Cruz County.

In that case, a state appeals court ruled last year that the California Department of Public Health conducted an insufficient review of a program run by the Harm Reduction Coalition of Santa Cruz County. The department didn’t do enough to consult with law enforcement agencies in the area, among other shortcomings, the court said.

Although the state health department had considered some comments from law enforcement, “it never engaged with them directly about their concerns,” the appeals court concluded. Internal records showed department staff had decided not to respond to some of their comments and called one police chief an “imbecile.”

Terrazas said local officials are best poised to know what works for their communities. But Denise Elerick, founder of the Harm Reduction Coalition of Santa Cruz County, argued it made no sense for law enforcement to hold sway in public health decisions.

“We wouldn’t consult with them on what to do about COVID,” Elerick said.

A bag is filled with boxes of Narcan nasal spray for distribution to people living on the street in Los Angeles.

Weeks after the court ruling, the state health department rolled back its approval for a syringe program in Orange County that would have been run by the Santa Ana-based Harm Reduction Institute, saying it wanted to consult more with local officials.

The decision was celebrated by city leaders in Santa Ana, who had banned syringe programs in 2020 and sharply opposed efforts to restart one. At a recent meeting, interim city manager Tom Hatch said a previous program was “an epic failure” that left its downtown littered with used syringes.

Orange County is currently the most populous county in the state without any syringe services programs — to the alarm of health researchers who found that syringe reuse increased after a local program was shut down.

The Santa Cruz court ruling was also invoked by the Santa Monica City Council, which directed city officials to investigate how Los Angeles County came to approve a program run by the Venice Family Clinic. That program sends outreach workers into Santa Monica parks once a week to offer clean syringes, Narcan and other supplies and connect people with healthcare, including for addiction.

A woman hands out Narcan to a man at Tongva Park in Santa Monica

Critics want the program to relocate indoors, which they say would better protect parkgoers from discarded syringes. In addition, “if someone has to walk inside, there’s a chance for counselors to suggest strongly that it’s time for them to get off the drugs,” said Santa Monica Mayor Phil Brock, who wants the city to formally express its opposition to the program. “We can’t just facilitate their demise.”

Last month, a group called the Santa Monica Coalition filed suit to get L.A. County to halt the program it approved, saying it should instead be in a government building.

But Venice Family Clinic staffers said unhoused people can be reluctant to leave behind their belongings to go elsewhere. Even offering services out of a van reduced participation, said Arron Barba, director of the clinic’s Common Ground program.

“Bringing the service directly to the people is what we know works,” Barba said.

Science

Pink Fire Retardant, a Dramatic Wildfire Weapon, Poses Its Own Dangers

Published

4 hours ago

January 10, 2025

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Pink Fire Retardant, a Dramatic Wildfire Weapon, Poses Its Own Dangers

From above the raging flames, these planes can unleash immense tankfuls of bright pink fire retardant in just 20 seconds. They have long been considered vital in the battle against wildfires.

But emerging research has shown that the millions of gallons of retardant sprayed on the landscape to tame wildfires each year come with a toxic burden, because they contain heavy metals and other chemicals that are harmful to human health and the environment.

The toxicity presents a stark dilemma. These tankers and their cargo are a powerful tool for taming deadly blazes. Yet as wildfires intensify and become more frequent in an era of climate change, firefighters are using them more often, and in the process releasing more harmful chemicals into the environment.

Some environmental groups have questioned the retardants’ effectiveness and potential for harm. The efficiency of fire retardant has been hard to measure, because it’s one of a barrage of firefighting tactics deployed in a major fire. After the flames are doused, it’s difficult to assign credit.

The frequency and severity of wildfires has grown in recent years, particularly in the western United States. Scientists have also found that fires across the region have become faster moving in recent decades.

There are also the longer-term health effects of exposure to wildfire smoke, which can penetrate the lungs and heart, causing disease. A recent global survey of the health effects of air pollution caused by wildfires found that in the United States, exposure to wildfire smoke had increased by 77 percent since 2002. Globally, wildfire smoke has been estimated to be responsible for up to 675,000 premature deaths per year.

Fire retardants add to those health and environmental burdens because they present “a really, really thorny trade-off,” said Daniel McCurry, an assistant professor of civil and environmental engineering at the University of Southern California, who led the recent research on their heavy-metal content.

The United States Forest Service said on Thursday that nine large retardant-spraying planes, as well as 20 water-dropping helicopters, were being deployed to fight the Southern California fires, which have displaced tens of thousands of people. Several “water scooper” amphibious planes, capable of skimming the surface of the sea or other body of water to fill their tanks, are also being used.

Two large DC-10 aircraft, dubbed “Very Large Airtankers” and capable of delivering up to 9,400 gallons of retardant, were also set to join the fleet imminently, said Stanton Florea, a spokesman for the National Interagency Fire Center in Boise, Idaho, which coordinates national wildland firefighting efforts across the West.

Sprayed ahead of the fire, the retardants coat vegetation and prevent oxygen from allowing it to burn, Mr. Florea said. (Red dye is added so firefighters can see the retardant against the landscape.) And the retardant, typically made of salts like ammonium polyphosphate, “lasts longer. It doesn’t evaporate, like dropping water,” he said.

The new research from Dr. McCurry and his colleagues found, however, that at least four different types of heavy metals in a common type of retardant used by firefighters exceeded California’s requirements for hazardous waste.

Federal data shows that more than 440 million gallons of retardant were applied to federal, state, and private land between 2009 and 2021. Using that figure, the researchers estimated that between 2009 and 2021, more than 400 tons of heavy metals were released into the environment from fire suppression, a third of that in Southern California.

Both the federal government and the retardant’s manufacturer, Perimeter Solutions, have disputed that analysis, saying the researchers had evaluated a different version of the retardant. Dan Green, a spokesman for Perimeter, said retardants used for aerial firefighting had passed “extensive testing to confirm they meet strict standards for aquatic and mammalian safety.”

Still, the findings help explain why concentrations of heavy metals tend to surge in rivers and streams after wildfires, sometimes by hundreds of times. And as scrutiny of fire suppressants has grown, the Forestry Service has set buffer zones surrounding lakes and rivers, though its own data shows retardant still inadvertently drifts into those waters.

In 2022, the environmental nonprofit Forest Service Employees for Environmental Ethics sued the government in federal court in Montana, demanding that the Forest Service obtain a permit under the Clean Water Act to cover accidental spraying into waterways.

The judge ruled that the agency did indeed need to obtain a permit. But it allowed retardant use to continue to protect lives and property.

Science

2024 Brought the World to a Dangerous Warming Threshold. Now What?

Published

12 hours ago

January 10, 2025

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2024 Brought the World to a Dangerous Warming Threshold. Now What?

Source: Copernicus/ECMWF

Note: Temperature anomalies relative to 1850-1900 averages.

At the stroke of midnight on Dec. 31, Earth finished up its hottest year in recorded history, scientists said on Friday. The previous hottest year was 2023. And the next one will be upon us before long: By continuing to burn huge amounts of coal, oil and gas, humankind has all but guaranteed it.

The planet’s record-high average temperature last year reflected the weekslong, 104-degree-Fahrenheit spring heat waves that shuttered schools in Bangladesh and India. It reflected the effects of the bathtub-warm ocean waters that supercharged hurricanes in the Gulf of Mexico and cyclones in the Philippines. And it reflected the roasting summer and fall conditions that primed Los Angeles this week for the most destructive wildfires in its history.

“We are facing a very new climate and new challenges, challenges that our society is not prepared for,” said Carlo Buontempo, director of the Copernicus Climate Change Service, the European Union monitoring agency.

But even within this progression of warmer years and ever-intensifying risks to homes, communities and the environment, 2024 stood out in another unwelcome way. According to Copernicus, it was the first year in which global temperatures averaged more than 1.5 degrees Celsius, or 2.7 degrees Fahrenheit, above those the planet experienced at the start of the industrial age.

For the past decade, the world has sought to avoid crossing this dangerous threshold. Nations enshrined the goal in the 2015 Paris agreement to fight climate change. “Keep 1.5 alive” was the mantra at United Nations summits.

Yet here we are. Global temperatures will fluctuate somewhat, as they always do, which is why scientists often look at warming averaged over longer periods, not just a single year.

But even by that standard, staying below 1.5 degrees looks increasingly unattainable, according to researchers who have run the numbers. Globally, despite hundreds of billions of dollars invested in clean-energy technologies, carbon dioxide emissions hit a record in 2024 and show no signs of dropping.

One recent study published in the journal Nature concluded that the absolute best humanity can now hope for is around 1.6 degrees of warming. To achieve it, nations would need to start slashing emissions at a pace that would strain political, social and economic feasibility.

But what if we’d started earlier?

By spewing heat-trapping gases into the atmosphere, humankind has lifted global temperatures to record highs.

If nations had started reducing emissions in 2005, they could have made gradual cuts to limit warming to 1.5 degrees.

Starting in 2015, when the Paris agreement was adopted, would have required steeper cuts.

Starting today would require cuts so drastic as to appear essentially impossible.

“It was guaranteed we’d get to this point where the gap between reality and the trajectory we needed for 1.5 degrees was so big it was ridiculous,” said David Victor, a professor of public policy at the University of California, San Diego.

The question now is what, if anything, should replace 1.5 as a lodestar for nations’ climate aspirations.

“These top-level goals are at best a compass,” Dr. Victor said. “They’re a reminder that if we don’t do more, we’re in for significant climate impacts.”

The 1.5-degree threshold was never the difference between safety and ruin, between hope and despair. It was a number negotiated by governments trying to answer a big question: What’s the highest global temperature increase — and the associated level of dangers, whether heat waves or wildfires or melting glaciers — that our societies should strive to avoid?

The result, as codified in the Paris agreement, was that nations would aspire to hold warming to “well below” 2 degrees Celsius while “pursuing efforts” to limit it to 1.5 degrees.

Even at the time, some experts called the latter goal unrealistic, because it required such deep and rapid emissions cuts. Still, the United States, the European Union and other governments adopted it as a guidepost for climate policy.

Christoph Bertram, an associate research professor at the University of Maryland’s Center for Global Sustainability, said the urgency of the 1.5 target spurred companies of all kinds — automakers, cement manufacturers, electric utilities — to start thinking hard about what it would mean to zero out their emissions by midcentury. “I do think that has led to some serious action,” Dr. Bertram said.

But the high aspiration of the 1.5 target also exposed deep fault lines among nations.

China and India never backed the goal, since it required them to curb their use of coal, gas and oil at a pace they said would hamstring their development. Rich countries that were struggling to cut their own emissions began choking off funding in the developing world for fossil-fuel projects that were economically beneficial. Some low-income countries felt it was deeply unfair to ask them to sacrifice for the climate given that it was wealthy nations — and not them — that had produced most of the greenhouse gases now warming the world.

“The 1.5-degree target has created a lot of tension between rich and poor countries,” said Vijaya Ramachandran, director for energy and development at the Breakthrough Institute, an environmental research organization.

Costa Samaras, an environmental-engineering professor at Carnegie Mellon University, compared the warming goals to health officials’ guidelines on, say, cholesterol. “We don’t set health targets on what’s realistic or what’s possible,” Dr. Samaras said. “We say, ‘This is what’s good for you. This is how you’re going to not get sick.’”

“If we were going to say, ‘Well, 1.5 is likely out of the question, let’s put it to 1.75,’ it gives people a false sense of assurance that 1.5 was not that important,” said Dr. Samaras, who helped shape U.S. climate policy from 2021 to 2024 in the White House Office of Science and Technology Policy. “It’s hugely important.”

Scientists convened by the United Nations have concluded that restricting warming to 1.5 degrees instead of 2 would spare tens of millions of people from being exposed to life-threatening heat waves, water shortages and coastal flooding. It might mean the difference between a world that has coral reefs and Arctic sea ice in the summer, and one that doesn’t.

Each tiny increment of additional warming, whether it’s 1.6 degrees versus 1.5, or 1.7 versus 1.6, increases the risks. “Even if the world overshoots 1.5 degrees, and the chances of this happening are increasing every day, we must keep striving” to bring emissions to zero as soon as possible, said Inger Anderson, the executive director of the United Nations Environment Program.

Officially, the sun has not yet set on the 1.5 target. The Paris agreement remains in force, even as President-elect Donald J. Trump vows to withdraw the United States from it for a second time. At U.N. climate negotiations, talk of 1.5 has become more muted compared with years past. But it has hardly gone away.

“With appropriate measures, 1.5 Celsius is still achievable,” Cedric Schuster, the minister of natural resources and environment for the Pacific island nation of Samoa, said at last year’s summit in Azerbaijan. Countries should “rise to the occasion with new, highly ambitious” policies, he said.

To Dr. Victor of U.C. San Diego, it is strange but all too predictable that governments keep speaking this way about what appears to be an unachievable aim. “No major political leader who wants to be taken seriously on climate wants to stick their neck out and say, ‘1.5 degrees isn’t feasible. Let’s talk about more realistic goals,’” he said.

Still, the world will eventually need to have that discussion, Dr. Victor said. And it’s unclear how it will go.

“It could be constructive, where we start asking, ‘How much warming are we really in for? And how do we deal with that?’” he said. “Or it could look very toxic, with a bunch of political finger pointing.”

Methodology

The second chart shows pathways for reducing carbon emissions that would have a 66 percent chance of limiting global warming this century to 1.5 degrees Celsius above the preindustrial average.

Science

U.S. Efforts to Cut Emissions Stalled in 2024 as Power Demand Surged

Published

20 hours ago

January 9, 2025

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U.S. Efforts to Cut Emissions Stalled in 2024 as Power Demand Surged

America’s efforts to cut its climate change pollution stalled in 2024, with greenhouse gas emissions dropping just a fraction, 0.2 percent, compared to the year before, according to estimates published Thursday by the Rhodium Group, a research firm.

Despite continued rapid growth in solar and wind power, emissions levels stayed relatively flat last year because demand for electricity surged nationwide, which led to a spike in the amount of natural gas burned by power plants.

The fact that emissions didn’t decline much means the United States is even further off-track from hitting President Biden’s goal of slashing greenhouse gases 50 percent below 2005 levels by 2030. Scientists say all major economies would have to cut their emissions deeply this decade to keep global warming at relatively low levels.

Since 2005, United States emissions have fallen roughly 20 percent, a significant drop at a time when the economy has also expanded. But to meet its climate goals, U.S. emissions would need to decline nearly 10 times as fast each year as they’ve fallen over the past decade. That seems increasingly unlikely, experts say, especially since President-elect Donald J. Trump has promised to dismantle Mr. Biden’s climate policies and promote the production of fossil fuels, the burning of which generates greenhouse gases.

“On the one hand, it is notable that we’ve now seen two years in a row where the U.S. economy grew but emissions went down,” said Ben King, an associate director at the Rhodium Group. “But it’s far from enough to achieve our climate targets.”

The biggest reason that U.S. emissions have fallen in recent years is that electric utilities have been retiring their older, dirtier coal-fired power plants and replacing them with cheaper and less-polluting natural gas, wind and solar power. That trend mostly continued last year, with a few unexpected ups and downs.

The nation’s demand for electricity, which has stayed more or less flat for two decades, suddenly jumped by roughly 3 percent in 2024, in large part because scorching heat during the summer caused many Americans to crank up their air-conditioners. A smaller factor was that tech companies have been building more energy-hungry data centers in states like Virginia and Texas.

While power companies installed large numbers of wind turbines, solar panels and batteries last year to meet rising demand, natural gas use also rose to record highs, while coal use declined only slightly. The net result was that emissions from the power sector increased an estimated 0.2 percent, according to the Rhodium Group.

At the same time, transportation, the nation’s largest source of greenhouse gases, saw an 0.8 percent rise in emissions last year. Gasoline and jet fuel consumption both increased as Americans continued to drive and fly more after the pandemic. Nearly 10 percent of new car sales in 2024 were less-polluting electric vehicles, but those models still make up a small fraction of total cars on the road and have yet to put a major dent in transportation emissions.

On the flip side, emissions from America’s industrial sector — which includes steel, cement and chemicals — fell by 1.8 percent in 2024. Some of that may have been the result of lost output, as two hurricanes and a strike at the nation’s ports disrupted some factory activity in the fall, Mr. King said.

“It’s a reminder that there’s always some bumpiness in emissions,” Mr. King said. “It’s not just a question of how many electric vehicles are on the road or how much solar we’ve installed. A big portion of our economy still relies on fossil fuels.”

One of the most striking findings in this year’s data was that emissions from oil and gas operations dropped roughly 3.7 percent in 2024. Even though the United States produced record amounts of oil and near-record amounts of natural gas last year, many companies appear to have curbed leaks of methane, which is the main ingredient in natural gas and which can seep into the atmosphere and contribute significantly to global warming.

Over the past few years, the Biden administration and several states have adopted new regulations that require oil and gas producers to detect and fix methane leaks. Many companies also have financial incentives to capture methane to sell rather than vent it into the air.

Between 2014 and 2024, U.S. companies appear to have reduced the amount of methane that escaped, per each cubic feet of gas they produced, by 40 percent, according to the Rhodium Group.

Several experts have estimated that greenhouse gases generated in the United States could start dropping sharply in the years ahead if many clean energy policies stay in place, particularly the 2022 Inflation Reduction Act that pumped hundreds of billions of dollars into low-carbon energy technologies such as electric vehicles, wind turbines, solar panels, nuclear reactors, green hydrogen and batteries.

While Mr. Trump has pledged to scrap many of Mr. Biden’s subsidies and tax credits for electric vehicles and low-carbon energy, it remains to be seen whether Congress will agree.

That law has not yet had a major impact on the country’s emissions, said Mr. King, since it takes time for new factories to open and power plants to get built. But, he said, data shows that low-carbon energy and transportation now make up fully 5 percent of total U.S. private investment.

“That’s a leading indicator that things are changing quickly,” he said.