With the onset of the coronavirus pandemic, experts have noticed that global carbon emissions have been significantly reduced. For many, this has become an indicator of how much we pollute the air.

According to NASA, global emissions of nitrogen dioxide, in addition to carbon, fell by 20%. Such a drop turned out to be astonishing to many.

“In a sense, I was surprised by such a reduction in [emissions],” said NASA researcher Christoph Keller. “Nitrogen dioxide emissions in many countries have already declined in recent decades.”

Comparison with pre-pandemic rates of air pollution is somewhat problematic because pollution is variable. Therefore, NASA researchers have created a model that predicts what emissions would be like this year if the pandemic had not started.

If you did not take preventive measures around the world, emissions of nitrogen dioxide in many large cities would be 20-50% higher.

Nitrogen dioxide emissions are largely caused by the combustion of fossil fuels (coal, gas, oil). Cars are the main source of this pollution in cities. It is therefore not surprising that with the reduction of road traffic, nitrogen dioxide emissions have also been reduced in many places.