Global carbon dioxide emissions could fall by up to 7 per cent this year, depending on continuing restrictions and physical-distancing measures during the new coronavirus pandemic, research published in the journal Nature Climate Change showed on Tuesday.
The study, by a group of scientists from institutions in Europe, the United States and Australia, analyzed daily carbon dioxide emissions across 69 countries, 50 U.S. states, 30 Chinese provinces, six economic sectors and three levels of confinement, using data from daily electricity use and mobility tracking services.
In 2019, the world emitted around 100 million tonnes of carbon dioxide a day by burning fossil fuels and cement production, the research said.
In early April, 2020, emissions fell to 83 million tonnes a day, a drop of 17 per cent, and some countries’ emissions dropped by as much as 26 per cent on average during the peak of the confinement.
If prepandemic conditions return by mid-June, then 2020 emissions could decline by 4 per cent compared with 2019, but if restrictions remain worldwide until the end of the year, then emissions could drop by 7 per cent, the report added.
This would be the largest single annual decrease in absolute emissions since the end of Second World War.
A UN report last year said emissions needed to drop by 2.7 per cent a year to keep warming well below 2 C, and 7.6 per cent a year to keep below 1.5 C.
“Population confinement has led to drastic changes in energy use and CO2 emissions,” said lead author Corinne Le Quéré at the University of East Anglia.
“These extreme decreases are likely to be temporary, however, as they do not reflect structural changes in the economic, transport or energy systems,” she added.
China saw the largest drop in emissions in April, followed by the U.S., Europe and India.
In the countries with the strictest lockdown restrictions, emissions from aviation plunged 75 per cent in early April, while emissions from land transport fell by 50 per cent and from power generation by 15 per cent.
Emissions from industry declined by around 35 per cent, with a lack of data causing some uncertainty. Emissions from residential buildings, however, increased by 5 per cent, the study said.
“The emissions reductions occurring because of COVID-19 will clearly be unprecedented. What is less certain is how the economy will rebound in late 2020 and 2021,” said Glen Peters at the Cicero Center for International Climate Research in Norway, which took part in the study.
“As different countries and sectors recover, it is unclear if activity levels will return to normal levels or if we may see permanent shifts in behaviour,” he added.
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