NASA and European Space Agency (ESA) pollution monitoring satellites have detected significant decreases in nitrogen dioxide (NO2) over China. There is evidence that the change is at least partly related to the economic slowdown following the outbreak of coronavirus, reports the NASA Earth Observatory on its website.
These readings by NASA and ESA might be the best evidence about how mankind is co-responsible for the polluting of the atmosphere by the influence of factories, transportation et cetera. And its all to do with the new coronavirus (COVID-19) which made the Chinese authorities shut down transportation going into and out of the Chinese city of Wuhan, as well as local businesses, in order to reduce the spread of the disease. It was the first of several quarantines set up in the country and around the world. NASA published two maps showing concentrations of nitrogen dioxide, a noxious gas emitted by motor vehicles, power plants, and industrial facilities.
The map shown here shows NO2 values across China from January 1-20, 2020 (before the quarantine) and February 10-25 (during the quarantine). The data were collected by the Tropospheric Monitoring Instrument (TROPOMI) on ESA’s Sentinel-5 satellite. A related sensor, the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite, has been making similar measurements, as explained on the website. The drop in nitrogen dioxide in 2020 also coincided with Lunar New Year celebrations in China and much of Asia. Generally, businesses and factories close from the last week in January into early February to celebrate the festival. Past observations have shown that air pollution usually decreases during this period and then increases once the celebration is over. But now the increase is not (yet) there. “This year, the reduction rate is more significant than in past years and it has lasted longer,” said Fei Liu, air quality researcher at NASA’s Goddard Space Flight Center.
Source: NASA Earth Observatory images by Joshua Stevens, using modified Copernicus Sentinel 5P data processed by the European Space Agency. Story by Kasha Patel with assistance from NASA Aura and NASA SPoRT science teams