Pollution levels in China to Italy dropped dramatically after people were forced to stay home to halt the spread of the coronavirus and the United States is no different.
Using data from the European Space Agency's Sentinel-5P satellite, the images first posted by Pattrn, a subset of the Weather Channel, show a correlation between the decrease of nitrogen dioxide levels in the atmosphere in cities like New York, Chicago and Los Angeles, and the period of time when people started to limit outdoor activities due to the virus.
Nitrogen dioxide is an air pollutant which mostly comes from heating, power generation, engines in vehicles and ships, according to the World Health Organization.
When the coronavirus began spreading in Wuhan, China, in December 2019, Sentinel-5P images showed a huge cloud of nitrogen dioxide over the country. But when compared to the data in February, the emission of the pollutant seems to have significantly decreased.
NASA scientists said that similar emissions reductions have been observed in other countries during economic disruptions, NBC News reported.
"This is the first time I have seen such a dramatic dropoff over such a wide area for a specific event," Fei Liu, an air quality researcher at NASA's Goddard Space Flight Center, said in a statement this month.
Here it is observed in Europe after the virus started spreading rapidly in Italy.
To date, over 470,000 people around the world have been infected with the coronavirus and over 21,000 people have died.