America’s greenhouse gas emissions from energy and industry plummeted more than 10 percent last year, reaching their lowest levels in at least three decades as the pandemic slammed the brakes on the nation’s economy, according to an estimate published Tuesday by the Rhodium Group.
The steep drop was the result of extraordinary circumstances, however, and experts say the United States still faces enormous challenges in getting its planet-warming pollution under control.
“The most significant reductions last year were around transportation, which remains heavily dependent on fossil fuels,” said Kate Larsen, a director at Rhodium Group, a research and consulting firm. “But as vaccines become more prevalent, and depending on how quickly people feel comfortable enough to drive and fly again, we’d expect emissions to rebound unless there are major policy changes put in place.”
Transportation, the nation’s largest source of greenhouse gases, saw a 14.7 percent decline in emissions in 2020 as millions of people stopped driving to work and airlines canceled flights. Although travel started picking up again in the second half of the year as states relaxed lockdowns, Americans drove 15 percent fewer miles last year than in 2019.
Over all, the fall in emissions nationwide was the largest one-year decline since at least World War II, the Rhodium Group said. It put the United States within striking distance of one of the major goals of the Paris climate agreement, a global pact by nearly 200 governments to address climate change.
As part of that agreement, President Barack Obama had pledged that U.S. emissions would fall 17 percent below 2005 levels by last year. President Trump withdrew the country from the Paris accord, and before last year, it appeared that the United States would miss the emissions target. But America’s industrial emissions are now roughly 21.5 percent below 2005 levels.
Scientists say that even a big one-year drop is not enough to stop climate change. Until humanity’s emissions are essentially zeroed out and nations are no longer adding greenhouse gases to the atmosphere, the planet will continue to heat up. As if to underscore that warning, European researchers announced last week that 2020 was probably tied with 2016 as the hottest year on record.