11 Before-And-After Comparisons Show The Positive Effect Of Quarantine And How It's Reducing Pollution

The current global drop-off in nitrogen dioxide pollution is one-of-a-kind in recent history. Fei Liu, an air quality researcher at NASA’s Goddard Space Flight Center, has said that “This is the first time I have seen such a dramatic drop-off over such a wide area for a specific event.” The reduction in NO2 pollution was initially detected near Wuhan, from where the coronavirus spread. Soon, it spread across the country and around the world.

Liu recalls a drop in NO2 during the economic recession in 2008 in some countries, but the fall was gradual. A similar reduction was observed around the area of Beijing during the 2008 Olympics, but it was localized around this one city and pollution soon returned to previous levels as the event ended.

Nitrogen dioxide is emitted from industrial processes, power plants, and car engines and is believed to aggravate respiratory illnesses. According to Wired, “while not a greenhouse gas itself, the pollutant originated from the same activities and industrial sectors that that are responsible for a large share of the world’s carbon emissions and that drive global heating.”

For that reason, this unprecedented drop in air pollution offers a glimpse into what effects a potential low-carbon economy would have on the Earth. Paul Monks, professor of air pollution at the University of Leicester, called the current crisis “the largest scale experiment ever seen.” And, in fact, “this might give us some hope from something terrible [...] to see what can be achieved.”