Less Travel Helps Clean the Air

These are satellite images of China in early 2020. The color scale shows the amount of nitrogen dioxide (NO2) in the air.

What Is Nitrogen Dioxide? 

You can’t see nitrogen dioxide. It’s a gas made by cars, trucks, buses, power plants, and factories. Too much nitrogen dioxide causes smog and acid rain. It can make people sick, too. Nitrogen dioxide is partly to blame for respiratory infections and asthma. 
A Temporary Benefit  

Wuhan, China is where the first cases of COVID-19 were reported. To stop the spread of infection, China announced a quarantine. Travel stopped. Factories closed. A temporary benefit was a big drop in air pollution over China. At first, only the pollution over Wuhan decreased. But as the quarantine continued, the air pollution over China decreased. It could be seen from NASA satellites in space!  

Lesson Learned 

Even though it was temporary, we can learn from this environmental lesson. We know cars and trucks create air pollution when we travel. We know factories create air pollution. While we can’t stop working and traveling, we can make changes. Factories can be held to higher standards. Humans can make better choices when it comes to travel. Travelers could ride a bike, take the bus, carpool, or choose a “greener” vehicle.     

Nitrogen dioxide in the Northeast U.S.

By March 2020, COVID-19 spread to the United States. Many governors asked people to stay home from work and school. When people stopped working and driving, they made less pollution. So there was less nitrogen dioxide in the air. The difference could be seen in satellite images, especially over New York  City.  

 What Do You Think? What changes could you make to help the environment? 

Photo Credit: (t)NASA Earth Observatory, (b)NASA