Nitrous Oxide pollution levels have plummeted in China's major cities according to satellite images from Nasa and the European Space Agency. While a decrease following the Chinese New Year is to be expected according to NASA's Earth Observatory, the lockdown following the outbreak of the coronavirus has contributed to the concentration of nitrogen dioxide decreasing immensely, with Wuhan being the first place where this tendency started.
NASA goes on to quote itself:
"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. Liu recalls seeing a drop in NO2 over several countries during the economic recession that began in 2008, but the decrease was gradual. Scientists also observed a significant reduction around Beijing during the 2008 Olympics, but the effect was mostly localized around that city, and pollution levels rose again once the Olympics ended"
Additionally, Liu and colleagues have not seen a rebound in NO2 after the holiday. "This year, the reduction rate is more significant than in past years and it has lasted longer," she said. "I am not surprised because many cities nationwide have taken measures to minimize spread of the virus."