This year’s pandemic could cause the biggest percentage drop in global carbon dioxide emissions since World War II and the Great Depression, scientists said Tuesday.
But that’s not necessarily good news for combating climate change, as the drop is a one-off that will probably be quickly erased as economies rebound.
“Population confinement has led to drastic changes in energy use and CO2 emissions,” said Corinne Le Quéré, professor at the University of East Anglia who led the first peer-reviewed study into the pandemic’s emissions effects released Tuesday. But, “these extreme decreases are likely to be temporary … as they do not reflect structural changes in the economic, transport, or energy systems.”
The findings estimate that global carbon dioxide emissions this year could fall anywhere from 4.2 percent to 7.5 percent, depending on social distancing rules. The EU and the U.K. together could see emissions fall in the range of 5.1 percent to 8.5 percent. The only time in the last century that falls were steeper was in the 1930s and during the war, when emissions dropped by more than 10 percent.
At the peak of the lockdowns, emissions in countries were down by an average of 26 percent, the study found.
But as governments start easing confinement measures and economic activity and travel recover, pollution levels are expected to go up again.
“The emissions reductions occurring because of COVID-19 will clearly be unprecedented. What is less certain is how the economy will rebound in late 2020 and 2021,” said Glen Peters, research director at the CICERO Center for International Climate Research in Oslo and another author, adding it’s unclear whether behavioral changes triggered by the crisis will stick.
There’s some precedent for being skeptical of the durability of any reduction.
Global CO2 emissions fell by 1.4 percent in 2009 thanks to the global financial crisis but by 2010 emissions shot up by 5.1 percent, “well above the long-term average,” the study said.
That spells trouble for the Paris climate agreement. Before the pandemic, the world wasn’t on track to reach the pact’s more ambitious goal of limiting global warming to 1.5 degrees Celsius.
The scale of the fall actually underlines the difficulty in reaching that target, as cuts of this year’s magnitude would have to become an annual occurrence.
“You go through all this pain and it’s only 5 percent … it does clearly show that reducing emissions is not going to be so easy. Emissions touch our lives in so many different aspects, we’re completely intertwined with energy and emissions, we’ve got to do something everywhere to reduce emissions,” Peters said.
The study does give some indications of where policymakers should concentrate their efforts to cut emissions. Transport, other than by plane, accounted “for nearly half the decrease in emissions during confinement,” suggesting that incentives for walking and cycling can help cut CO2 emissions in the future. Reductions in industry and power sector emissions were another major driver of daily declines. The aviation sector, while hardest hit by confinement, contributed much less to the decline in emissions, at 10 percent.
The challenge is now trying to ensure that the trillions of recovery cash governments are pumping into their economies should be directed toward technologies and sectors that could have an impact on climate change.
“The extent to which world leaders consider the net-zero emissions targets and the imperatives of climate change when planning their economic responses to COVID-19 is likely to influence the pathway of CO2 emissions for decades to come,” the study said.