A jump in coal-fired power helped drive the increase, according to a report from the Rhodium Group. 

U.S. greenhouse gas emissions roared back in 2021, the latest indicator that the country remains far off track from meeting President Biden’s ambitious climate change targets for the end of this decade.

A 17 percent surge in coal-fired electricity helped drive an overall increase of 6.2 percent in greenhouse gas emissions compared with the previous year, according to an analysis published Monday by the Rhodium Group. While emissions remained below pre-pandemic levels, it marked the first annual increase in reliance on the nation’s dirtiest fossil fuel since 2014, the independent research firm said.

The rise in the nation’s emissions, which many experts anticipate will continue this year, is a sign of an economy on the mend. But it also signals a potentially ominous climate reality: The United States is not yet emerging from the coronavirus pandemic with a greener economy, making it that much harder for Biden to deliver on his pledge to cut the nation’s emissions in half by 2030.

“In an ideal world, we want the economy to rebound, but not the emissions,” Kate Larsen, a co-author of the analysis who leads Rhodium’s international energy and climate research, said in an interview.

Larsen added that the surge in coal generation was “almost entirely due to high natural gas prices” as oil and gas producers curbed new production in response to lower global demand because of pandemic lockdowns. “Emissions from our power sector were pretty much at the whim of energy markets,” she said.

The nation’s largest source of greenhouse gas emissions — transportation — also saw the steepest rebound during 2021, rising 10 percent over the previous year, Rhodium found. The arrival of coronavirus vaccines and the nation’s fitful efforts to emerge from the pandemic meant more Americans traveled on roads and in the skies than in 2020. But road freight was the only mode of transportation that rebounded to pre-pandemic levels, as thousands of diesel-powered trucks rumbled along the nation’s highways to deliver consumer goods.

Last spring, Biden vowed to launch an all-of-government effort to cut U.S. carbon pollution 50 to 52 percent by 2030, compared with 2005 levels, and to put the nation on track to reach net-zero emissions by 2050.

“We’re going to cut U.S. greenhouse gas emissions by well over a gigaton by 2030, while making it more affordable for consumers to save on their own energy bills with tax credits for things like installing solar panels, weatherizing their homes, lowering energy prices,” Biden told fellow world leaders at a United Nations climate summit in Glasgow, Scotland, in November.

He promised to electrify school bus fleets, increase tax credits for electric vehicles, ramp up construction of solar panels and wind turbines and incentivize cleaner manufacturing — all while creating well-paying union jobs.

“We’ll demonstrate to the world the United States is not only back at the table but hopefully leading by the power of our example,” he said.

Biden used his executive authority during his first year in office to jump-start an array of climate policies, including proposing tougher tailpipe emissions standards for new cars and requiring the federal government to become carbon neutral by 2050. But a major piece of his climate agenda is stalled on Capitol Hill, where Democrats are still struggling to pass their roughly $1.75 trillion climate and social spending bill.

The Build Back Better Act contains a historic $555 billion package of tax credits, grants and other policies aimed at reducing emissions and boosting clean energy. But Sen. Joe Manchin III (D-W.Va.) said in late December that he could not support the legislation, potentially dooming its chances in the Senate.

John Podesta, who served as a counselor to President Barack Obama and chief of staff to President Bill Clinton, said that without Build Back Better, it will be impossible to meet Biden’s goal of halving U.S. emissions by 2030.

“I’ve been a proponent of executive action, particularly in the face of Republican opposition, going back to Clinton. And I certainly would urge them to use every tool they have. But without these investments, you just can’t get the job done,” said Podesta, who is also the founder of the Center for American Progress and a contributing columnist for The Washington Post.

Earth has warmed roughly 1.1 degrees Celsius since preindustrial times, and atmospheric concentrations of carbon dioxide and other potent gases, such as methane, have continued to rise. Two weeks of international talks last fall in Glasgow led to promises to reduce methane emissions, halt deforestation and stop the funding of coal power, but even then the U.N. Environment Program reported that the Earth remains on track to warm about 2.5 degrees Celsius (4.5 degrees Fahrenheit) by the end of the century — though other analyses suggested that that number could drop if countries took swift action to fulfill their long-term pledges.

Monday’s findings from Rhodium are in line with what other researchers have found: that a deadly global pandemic and a massive economic downturn have done little to slow the accumulation of planet-warming gases in the atmosphere.

Late last year, a collection of scientists from 70 institutions on five continents detailed how the world’s greenhouse gas emissions were rapidly rebounding after a brief slump during the height of the pandemic in 2020.

The Global Carbon Budget report, released in the middle of the U.N. climate talks in Glasgow, said the world has only about 11 years of burning fossil fuels at the current rate if it hopes to hit the most ambitious goal of the Paris climate agreement: to limit global temperature rise to 1.5 degrees Celsius (2.7 degrees Fahrenheit) above preindustrial levels.

But an initial drop in emissions that came in 2020 when the covid-19 pandemic shuttered factories, grounded planes and hindered economic activity across the globe proved to be little more than a blip on the world’s trajectory toward more warming.

One twist from 2021 that is unlikely to last, at least in the United States, is the sharp rise in burning coal for electricity, researchers said. Coal power has steadily declined over the past decade and now accounts for only about 19 percent of U.S. electricity generation, half that of natural gas, according to the Energy Information Administration.

“Clearly, coal use in the U.S. in the long term is going down,” said Corinne Le Quéré, a climate scientist at the University of East Anglia who was not involved with the Rhodium report. “The coal power stations are very old, and it would cost a lot of money to invest in them to put them up to shape. And that’s not the direction of travel because of climate policies.”

Rob Jackson, a professor at Stanford University and chair of the Global Carbon Project, said the United States, which has generated more greenhouse gases than any other country in history, must do more to flatten the curve of its emissions trajectory before the next U.N. climate summit in Egypt in November.

Biden’s credibility on the world stage depends on it, he said.

“Other countries will be looking at what commitments we have made,” Jackson said, adding that “they will look at us and say we’re not putting our money where our mouth is.”