Scientists believe that the improvements in air quality in China is linked to the efforts by the government to stem the spread of the Coronavirus.
Businesses across China have been closing and manufacturing has ground to a halt, causing a widespread fall in the world's economy. That means there are not only less factories open, but there are less cars on the road and planes in the air. That means nitrogen dioxide, a pollutant which comes primarily from the burning of fossil fuels, were down by as much as 30 percent, according to NASA.
NASA and European Space Agency pollution monitoring satellites issued two images which show a significant change in nitrogen dioxide levels in the air over the country between the start of the year and the end of February. In the satellite photos, a siginificant drop in airborne pollutants has been observed in major urban centers.
"This is the first time I have seen such a dramatic drop-off over such a wide area for a specific event," said Fei Liu, an air quality researcher at NASA's Goddard Space Flight Center.