WASHINGTON — Climate-altering pollution from greenhouse gases declined by nearly 2% in the United States in 2023, even as the economy expanded at a faster clip, a new report finds.

The decline, while “a step in the right direction,” is far below the rate needed to meet President Joe Biden's pledge to cut U.S. emissions in half by 2030, compared to 2005 levels, said a report Wednesday from the Rhodium Group, an independent research firm.

“Absent other changes,″ the U.S. is on track to cut greenhouse gas emissions by about 40% below 2005 levels by the end of the decade, said Ben King, associate director at Rhodium and lead author of the study.

The report said U.S. carbon emissions declined by 1.9% last year. Emissions are down 17.2% from 2005.

To reach Biden's goal, emissions would have to decline at a rate more than triple the 2023 figure and be sustained at that level every year until 2030, he said.

Increased economic activity, including more energy production and greater use of cars, trucks and airplanes, can be associated with higher pollution, although there is not always a direct correlation. The U.S. economy grew by a projected 2.4% in 2023, according to the Conference Board, a business research group.

Last year's relatively mild winter and continued declines in power generation from coal-fired plants drove down emissions in the U.S. power and buildings sectors, the report said.

At the same time, transportation sector emissions rose, led by a continued rebound in airplane travel and increased gasoline consumption as road traffic returns to pre-pandemic levels, the report said. Higher domestic oil and gas production also led to a small increase in industrial emissions.

While carbon emissions declined overall, “some ominous signs also began to appear in 2023,” the report said. Natural gas generation grew more than twice as fast as renewables in 2023, compared to 2022. And while solar installations were on track for another record year, installations of wind turbines were down compared to 2022 and 2021, the report said.

Rising construction and financing costs, along with supply-chain constraints and other issues, have cast doubt on wind power's once-robust growth. Two large offshore wind projects were canceled late last year, jeopardizing the Biden administration’s goal to power 10 million homes from huge ocean-based turbines by the end of the decade.

Biden and congressional Democrats passed the most sweeping climate law in U.S. history in 2022, but effects of the law, known as the Inflation Reduction Act, are just beginning to be felt and are unlikely to have a significant impact on emissions for a few years, King said.

The climate law, passed with only Democratic votes, authorizes nearly $375 billion in tax credits and other incentives to spur investors to accelerate clean energy such as solar and wind power, speeding the transition away from the burning of fossil fuels such as oil, coal and gas that largely cause climate change.

Congress also passed a bipartisan infrastructure law in 2021, and the Environmental Protection Agency has issued rules and proposals to crack down on methane emissions and pollution from coal-fired power plants, among other actions. Coal, long a mainstay of the U.S. electric grid, made up only 17% of U.S. generation in 2023, a record low, the report said.

U.S. oil production, meanwhile, hit an all-time high in 2023, contrasting with Biden's efforts to slice heat-trapping carbon emissions and conflicting with oft-repeated Republican talking points of a Biden “war on American energy.”

Methane leaks, along with venting and flaring of methane and carbon dioxide during oil and gas production and transportation, drove the bulk of industrial sector emissions increases in 2023, the report said. Rhodium estimates new EPA rules finalized last month will reduce greenhouse gas emissions from the oil and gas sector by nearly 40% compared to current levels.

Oil and gas operations are the largest industrial source of methane, the main component in natural gas and far more potent than carbon dioxide in the short term. It is responsible for about one-third of planet-warming greenhouse gas emissions. Sharp cuts in methane emissions are a global priority to slow the rate of climate change and were a major topic at a global climate conference in December known as COP28.

Turning the tide on industrial emissions will also require meaningful action to decarbonize other industries such as iron and steelmaking, cement manufacturing and chemical production, the report said.