Over the past six months, widespread lockdown measures to combat the spread of the coronavirus have led to notable declines in greenhouse gas emissions. But short-term gains are unlikely to have a significant impact on future warming if the world returns to business as usual, according to a new paper published on 7 August in Nature Climate Change (1).
An earlier study, also published in Nature Climate Change, reported a 17 per cent decrease in emissions due to lockdown strategies implemented in early April compared with mean 2019 levels, raising hopes that something positive might come out of the pandemic (2). However, the new analysis suggests that the overall effect on climate change may only amount to a minuscule reduction of 0.01 degrees Celcius in global temperature rise by 2030.
To come up with the numbers, the team of researchers pieced together open-source data from 123 countries – including previous research tracking carbon dioxide, mobility data, and historical data from air-quality monitoring stations – to examine changes in ten different greenhouse gases and air pollutants between February and June of 2020.
They found that global emissions have indeed fallen by around 10 to 30 per cent, on average, mainly due travel restrictions, which have dramatically reduced surface transport. Nonetheless, if the world goes back to its fossil-fuel burning ways, the drop in emissions due to lockdown measures is likely to be negligible in the long term.
While the study highlights the ‘limits of behaviour change’, the authors also stress that post-lockdown recovery plans that embrace green policies could prevent the world from exceeding 1.5 degrees Celcius of warming by 2050. So-called green initiatives, such as investing in low carbon technology and lowering traffic pollution by prioritising public transport and cycle lanes, would dramatically reduce emissions, the authors say. For example, an additional 1.2 per cent of gross domestic product invested in low carbon technology could cut emissions in half by 2030 compared with a fossil fuel-led recovery.
In a statement, lead author Prof Corinne Le Quéré, a climate scientist at the University of East Anglia, said: “The fall in emissions we experienced during COVID-19 is temporary, and therefore it will do nothing to slow down climate change. But the government responses could be a turning point if they focus on a green recovery, helping to avoid severe impacts from climate change.”
We are being presented with a unique opportunity for structural change to the global economy that should not be wasted. Senior author Prof Piers Forster from the University of Leeds, who initiated the study with daughter Harriet Forster while she was out of school during the COVID-19 lockdown, told the BBC News that he is optimistic:
“Disasters are often historically the time of biggest change. For once government, industry and public voices are all pretty aligned that green jobs and green investments are the way to build back better. We just need to do it.”
(1) Forster, P.M. et al. Current and future global climate impacts resulting from COVID-19. Nature Climate Change (2020). DOI: 10.1038/s41558-020-0883-0
(2) Le Quéré, C. et al. Temporary reduction in daily global CO2 emissions during the COVID-19 forced confinement. Nature Climate Change (2020). DOI: 10.1038/s41558-020-0797-x