The worldwide drop in carbon emissions due to coronavirus shutdowns could be the largest in recorded history, scientists say.
As of early April, daily global carbon dioxide emissions decreased by 17 percent compared to last year's levels, corresponding with emission levels of 2006, according to a study published Tuesday in Nature Climate Change. Scientists estimate an annual decrease of 4 to 7 percent, depending on when pre-pandemic activities resume.
Researchers analyzed 69 countries, representing 97 percent of global carbon dioxide emissions, and found 43 percent of the decrease stemmed from reduced surface transportation, including cars, trucks, and buses. All sectors examined had a decrease in emissions, except the residential sector, which saw a growth of 2.8 percent, likely from people staying home.
The decline isn't likely to be a huge step toward combating climate change, though, as carbon dioxide remains in the atmosphere for a long time, said Zeke Hausfather, a climate scientist at the University of California, Berkeley, reports NBC News. What matters is long-term systemic changes rather than single-year emissions. To make a meaningful difference, "We would have to have the same speed of reduction that's happening in 2020 every year for the next decade," Hausfather said.
But shutdown measures aren't the way to tackle climate change, said Corinne Le Quéré, professor of climate change science at the University of East Anglia in the U.K., and the study's lead author, per NBC News. "It's about governments having vision and being forward thinking. What society do we need to build tomorrow to reduce the risks of more disasters?"