L.A. coronavirus clean air streak has already come to an end. Here’s why

Source: By Sammy Roth, Los Angeles Times • Posted: Wednesday, April 29, 2020

It’s been hailed as a silver lining of the coronavirus lockdown: With fewer cars on the road, air quality has improved, bringing clearer skies to cities across the world.

Los Angeles had its longest streak of good air days in decades, and social media is full of photos of an unusually crisp skyline. “Coronavirus Got Rid of Smog,” proclaimed a headline in the Wall Street Journal.

So has L.A. smog been eliminated?

Not exactly.

While there is no question the restrictions to stem the pandemic have reduced air pollution, the coronavirus lockdown does not bear full responsibility for the weeks of clean air Californians have enjoyed. Dramatic reductions in vehicle and industrial emissions contributed to lower smog levels, air quality experts say, but much of the improvement was also due to stormy spring weather.

“We have the readings that show us that the air has been better, and presumably it’s not a coincidence that it happens at the same time that people are sheltering in place and the economy is at a fraction of its normal activity,” said Mary Nichols, who chairs the California Air Resources Board. But determining how much is due to weather versus pandemic-triggered emissions reductions, she said, “will take us a while to figure that one out.”

At least for now, scientists and regulators say, the situation offers an unintended glimpse at what the nation’s smoggiest region could be like with more electric vehicles on the road.