PARIS • The unprecedented fall in greenhouse gas emissions from lockdowns during the coronavirus pandemic will do "nothing" to slow climate change without a lasting switch from fossil fuels, an international team of researchers said yesterday.
Global emissions from the burning of coal, oil and gas could fall up to 8 per cent this year after governments moved to confine billions of people to their homes in a bid to slow the spread of Covid-19.
But absent a systemic change in how the world powers and feeds itself, experts warned in the study yesterday that the emissions saved during lockdown would be essentially meaningless.
Using open source data, the team calculated how levels of 10 different greenhouse gases and air pollutants changed in more than 120 countries between February and June this year. They found that pollution such as that from carbon dioxide and nitrogen oxides fell in the period by between 10 per cent and 30 per cent.
However, given that the "massive behavioural shifts" during lockdown were only temporary, lower emissions so far this year are unlikely to influence the climate.
Even assuming travel restrictions and social distancing continue till the end of next year, the team concluded this would save only 0.01 deg C of warming by 2030.
"Lockdown showed that we can change and change fast, but it also showed the limits of behaviour change," said Professor Piers Forster, study co-author and director of the Priestley International Centre for Climate at Britain's University of Leeds. "Without underlying structural change, we won't make it."
Under the 2015 Paris climate deal, nearly 200 nations agreed to limit temperature rises to "well below" 2 deg C above pre-industrial levels through sweeping emissions cuts. It also set a safer goal of a 1.5 deg C cap.
The United Nations says that in order to keep 1.5 deg C in play, global emissions must fall 7.6 per cent annually this decade. That is roughly equivalent to the anticipated emissions fall this year. But given that it took one of the largest economic slowdowns in history for this drop to happen, Prof Forster said it was unlikely to be repeated as nations look to recover.
The study, published in Nature Climate Change, also modelled options for post-lockdown recovery which the authors said showed a unique opportunity for structural change to the global economy.
Options for policymakers include lowering traffic pollution by prioritising public transport and cycle lanes.
A "strong green stimulus", which would see an additional 1.2 per cent of gross domestic product invested in low carbon technology, could slash emissions by half by 2030 compared with a fossil fuel-led recovery, the authors said.