Hello, Blue Sky—The Pandemic Reduces Air Pollution

If city dwellers, with heads down from the COVID-19 pandemic, were to look up, they would see blue skies.

Los Angeles, Calif., before and after COVID-19. (Image courtesy of Reuters)

Green is good. Note the number of good days in a row at bottom of the graph showing the last year of 25 years (Source: U.S. EPA Air Data).

A recent report showed the sky over Los Angeles smog free for a record number of days. Between March 16 and April 6, UCLA’s Dr. Yifang Zhu measured a 20 percent improvement in overall air quality in Southern California, according to CNN.

Fewer cars on the road, fewer office buildings being heated, and less power being generated have all combined to make for more “green” days in a row. Green represents good quality, with 50 or less on the air quality index, or AQI. Also, in mid-March, California Governor Gavin Newsom become the first U.S. governor to direct all state residents to stay home. This is not a coincidence.

In Los Angeles, the biggest contributor to air pollution is the automobile. After the governor’s order, traffic was reduced by 80 percent, says Zhu.

Elsewhere in the World

In Italy, which has been hit hard and early by the coronavirus, the canals in the city of Venice are running clear. Cruise ships that routinely dumped pollutants in the waters have stopped coming after COVID-19. While the local economy misses as many as 700,000 cruise visitors in a typical March, the city’s canals appreciate their absence.

Indian cities, with some of the worst air pollution on Earth, are clearing up. (Image courtesy of CNN)

Consumption of Chinese coal takes a dive after cities locked down and powerplants and factories stopped operating. (Image courtesy of CNN.)

Clear skies may not be the only unintended benefit of COVID-19. Air pollution has been directly linked to the number of COVID-19 deaths. A Harvard University research team studied the air quality of U.S. cities and compared them to the number of COVID-19 deaths that occurred within them. They concluded that a small increase (1 μg/m³) in PM2.5 (fine particles 2.5 microns or less) was associated with a 15 percent increase in the COVID-19 death rate.

None of the findings are a reason to celebrate, considering the sickness, death and loss of jobs caused by COVID-19. Also, COVID-19 will not last forever, and pollution sources are bound to pick up where they left off when the pandemic subsides. But the blue skies and clear waters offer hope, showing what little we need to do reverse a trend and how quickly the Earth can heal.