The unprecedented fall in greenhouse gas emissions from lockdowns during the 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 eight percent in 2020 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 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 carbon dioxide and nitrogen oxides fell in the period by between 10 and 30 percent.
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 to the end of 2021, the team concluded that this would only save 0.01 C of warming by 2030.
"Lockdown showed that we can change and change fast, but it also showed the limits of behaviour change," 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," he told AFP.
The 2015 Paris climate deal saw nations commit to limit temperature rises to "well below" two degrees Celsius above pre-industrial levels through sweeping emissions cuts. It also set a safer goal of a 1.5 C cap.
The UN says that in order to keep 1.5 C in play global emissions must fall 7.6 percent annually this decade. That is roughly equivalent to the anticipated emissions fall this year. But to achieve that its caused one of the largest economic slowdowns in history. Forster said it was unlikely to be repeated as countries look to recover.
The study, published in Nature Climate Change, pinned hope on post-lockdown recovery which the authors said showed a unique opportunity for structural change to the global economy.