Factories were shuttered and streets were cleared across China’s Hubei province as authorities ordered residents to stay home to stop the spread of the coronavirus.
It seems the lockdown had an unintended benefit – blue skies.
The average number of “good quality air days” increased 21.5% in February, compared to the same period last year, according to China’s Ministry of Ecology and Environment.
And Hubei wasn’t alone.
Satellite images released by NASA and the European Space Agency show a dramatic reduction in nitrogen dioxide emissions – those released by vehicles, power plants and industrial facilities – in major Chinese cities between January and February. The visible cloud of toxic gas hanging over industrial powerhouses almost disappeared.
“This is the first time I have seen such a dramatic drop-off over such a wide area for a specific event,” says Fei Liu, an air quality researcher at NASA’s Goddard Space Flight Center. “I am not surprised because many cities nationwide have taken measures to minimize the spread of the virus.”
A similar pattern has emerged with carbon dioxide (CO2) – released by burning fossil fuels such as coal.
From February 3 to March 1, CO2 emissions were down by at least 25% because of the measures to contain the coronavirus, according to the Center for Research on Energy and Clean Air (CREA), an air pollution research organization.
As the world’s biggest polluter, China contributes 30% of the world’s CO2 emissions a