A new study says emissions from gas and highly polluting coal will rise this year by more than they dropped in 2020 due to the Covid-driven economic slowdown.
Global CO2 emissions caused mainly by burning fossil fuels are set to rebound in 2021 to pre-Covid levels, with China's share increasing to nearly a third of the total.
An annual report from the Global Carbon Project consortium published on Thursday shows that overall, CO2 pollution this year will be just shy of the record set in 2019.
"This report is a reality check," co-author Corrine Le Querre, a professor of climate change science at the Britain's University of East Anglia, told the AFP news agency.
The study projected total global emissions this year to reach 36.4 billion tons of CO2, saying emissions from gas and highly polluting coal will rise this year by more than they dropped in 2020 due to the pandemic-driven economic slowdown.
Capping the rise in global temperature to 1.5 degrees Celsius above pre-industrial levels – as per the Paris Agreement – would limit mortality and damage.
However this requires slashing carbon emissions nearly in half by 2030 and to net-zero by 2050, the UN's climate science authority has warned.
'Mostly about coal'
Among major emitters, China and India are expected to post higher emissions in 2021 than in 2019, while the United States and Europe are expected to have slightly slower emissions.
China was an outlier in 2020 because investments to spur pandemic recovery led to large increases in coal use, even as emissions in other countries dropped.
2021 emissions in the US and EU will drop 3.7 and 4.2 percent, respectively, and their share of global emissions will stand at 14 and 7 percent.
The wild card that could determine how quickly the world can finally bend th e emissions downward is coal, the report made clear.
"Mostly it's about coal now," said Le Quere. "This is where the big uncertainties are."
Very little of the trillions of dollars chanelled to post-pandemic recovery was earmarked for green development, a trend that is continuing, she said.
It comes as global leaders meet at a UN climate conference in Glasgow, Scotland, to try to limit temperature rise to 1.5 degrees Celsius and avoid the most catastrophic effects of climate change. In order to do so, scientists say, CO2 emissions must reach net zero by 2050.