CO2 emissions fell further in the first half of 2020 than during the financial crisis of 2008, the oil crisis of 1979 and even the second world war.
In a paper published in Nature Communications, researchers showed that in the first six months of this year, emissions were down 8.8% compared to the same period in 2019 – a total decrease of 1,551 million tonnes of CO2.
By looking at the daily figures compiled by the carbon monitor research initiative, the researchers were able to produce a “much faster and more accurate overview”, including timelines showing how emissions have corresponded to lockdown measures in each country.
For instance, in April, at the height of the first wave of coronavirus infections, when most major countries shut down their public life and parts of their economy, emissions dropped by 16.9%. But since then there have been “strong rebound effects”. Emissions from transport have remained low, but as soon as lockdown measures were lifted, “most economies resumed their usual levels of emitting CO2”, the experts said.
The paper also outlines the scale of the challenge to reduce emissions in line with the Paris Agreement. Even if emissions remained at their historically low levels, this would have a “rather minuscule” effect on the long-term CO2 concentration in the atmosphere.
“While the CO2 drop is unprecedented, decreases of human activities cannot be the answer,” said co-author Hans Joachim Schellnhuber, founding director of the Potsdam Institute for Climate Impact Research. “Instead we need structural and transformational changes in our energy production and consumption systems. Individual behaviour is certainly important,” he added, “but what we really need to focus on is reducing the carbon intensity of our global economy.”