The empty Champs Elysees avenue is pictured in Paris, France on March 28, 2020. The country has fined people who violate its statewide lockdown measures to stop the spread of COVID-19.
Pascal Le Segretain | Getty Images
Global greenhouse gas emissions have decreased by around 2.4 billion tons this year, a 7% decrease from 2019 and the largest decrease in history triggered by global Covid-19 restrictions. This is the result of new research from the University of East Anglia, the University of Exeter and the University of East Anglia, the Global Carbon Project.
The researchers said carbon emissions are likely to rise again in 2021, and urged governments to prioritize a shift to clean energy and action to combat climate change in their recovery plans.
Daily global carbon emissions fell 17% during the peak of the pandemic lockdowns in April, but have since risen again, approaching 2019 levels, according to the report published Thursday in Earth System Science Data.
"All the elements to sustainably reduce global emissions are not yet in place, and emissions are slowly falling back to 2019 levels," Corinne Le Quere, professor at the UEA's School of Environmental Sciences, said in a statement.
"Government action to stimulate the economy at the end of the Covid-19 pandemic can also help cut emissions and combat climate change," she added.
The US saw the largest drop in CO2 emissions at 12%, followed by the European Union at 11%, the report said. In both cases, pandemic restrictions accelerated the decline in the use of coal in power generation and oil in transportation.
In developing countries, CO2 emissions fell by 9% in India, but only by 1.7% in China. China's lockdown took place earlier in the year and was shorter in duration. In addition to the country's rising CO2 emissions, there have been restrictions on CO2 emissions.
A decline in transport activity led to a global decrease in CO2 emissions. Emissions from automobiles and air travel fell by about half during the peak of Covid restrictions in April, and by December they were down about 10% and 40%, respectively, from 2019, according to the report.
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"Incentives that help accelerate the use of electric cars and renewables and encourage walking and cycling in cities are particularly timely given the significant disruption seen in the transport sector this year," said Le Quere.
The historical decline in global emissions has also had a negligible impact on the levels of carbon in the atmosphere, which are warming the earth and worsening climate catastrophes, melting ice, and rising sea levels.
In 2020 alone, forest fires caused by climate change burned a record amount of land in the western United States, and the most active hurricane season in the Atlantic devastated Central America and the Gulf Coast states.
"The climate system is powered by the total amount of CO2 that has been released into the atmosphere over centuries," said Glen Peters, Research Director of International Climate Research in Norway and a member of the Global Carbon Project.
"Although emissions decreased in 2020, they were still at 2012 levels and the decrease is insignificant compared to the total amount of CO2 emitted over the past few centuries," he said.
While global carbon emissions have steadily increased over the past few decades, researchers have found that emissions growth has increased more slowly in recent years, mainly due to changes in coal production.
"Global warming stops when emissions go to zero and Covid-19 hasn't changed that," Peters said.