Researchers have revealed more details of how China’s coronavirus lockdowns reduced air pollution.
The research is part of a special collection of papers published by the American Association for the Advancement of Science in the journal Science Advances. The papers examine how pandemics affect – and are affected by – global environmental conditions.
The coronavirus first emerged last December in the Chinese city of Wuhan, scientists said.
Research Scientist Fei Liu of the Universities Space Research Association (USRA) and colleagues said they harnessed satellite data to measure pollution during the pandemic. In the first research paper, scientists used the satellite information to identify an average 48-percent drop in nitrogen dioxide (NO2) densities over China from 20 days before to 20 days after the Lunar New Year on Jan. 25, 2020.
“While this greenhouse gas - an indicator of fossil fuel consumption - typically decreases during the holiday, when traffic slows and most Chinese factories close, Fei Liu and colleagues observed that the reduction was about 21 percent greater than in 2015 through 2019,” the researchers said in a statement. “Fei Liu and colleagues conclude that this enhanced nitrogen dioxide reduction correlated to government announcements of the first reported COVID-19 case in each province and to the initiation of lockdowns, which further subdued both travel and business activity.”
The findings underlined the extent of pre-pandemic pollution, according to scientists.
"Economic lockdowns this year, designed to slow the spread of COVID-19, have been like pressing the pause button on environmental degradation and the resulting reductions in air and water pollution are dramatic," wrote Kip Hodges and Jeremy Jackson in an editorial that introduced the special collection. "Such trends remind us of how much our actions drive environmental quality and just how badly we have behaved as stewards of our planet."
Researchers said they monitored shifts in atmospheric nitrogen oxide.
Greenhouse gas emissions have been in the spotlight amid the coronavirus pandemic. In early March, satellite images from NASA and the European Space Agency spotted an enormous decline in airborne pollutants, specifically nitrogen dioxide, in large areas of China.
Over 84,000 coronavirus cases have been diagnosed in China, accounting for over 4,600 deaths, according to data from Johns Hopkins University. Many critics have blasted China over its reporting of infections and deaths, saying the true figures have been much higher.
Coronavirus lockdowns have affected pollution across the globe, according to experts.
As of Monday afternoon, over 7.9 million coronavirus cases have been diagnosed worldwide, with over 2.1 million in the U.S., according to Johns Hopkins. The disease has accounted for over 434,000 deaths around the world, including nearly 116,000 in the U.S.
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