Will Cleaner Air Because of Stay-At-Home Order (and Maybe the Rain) Lead to Lifestyle Changes?

There’s a deadly virus. You're stuck at home. You're out of work. You can’t see your friends or have a drink in a bar. And there's no immediate end in sight. All bad news all the time.

But can you take a deep breath and look on the bright side?

The answer at least for the moment is "yes."

During the last few weeks, the air quality in Southern California officially has been cleaner, a fact that has gotten the attention of climate change advocates and proponents for reducing emissions.

"The last time I ever saw this kind of beautiful clear sky was a really long time ago," said Rima Habre, assistant professor of clinical preventive medicine at USC’s Keck School of Medicine’s Division of Environmental health.

Tuesday’s haze altered the course of three weeks of primarily blue sky and South Coast Air Quality Management District maps that showed nothing but good air quality across Southern California. On Tuesday, a few patches of unhealthful air made their way onto the color-coded maps.

But to those in the know, there was no doubt that the lack of cars and trucks on the road, and everybody staying at home, had some sort of impact on the air.

"You see this everywhere," Habre said. "The entire globe – over in and Delhi and Paris, Spain, Italy. China, Korea, Lebanon, where I'm from, everywhere."

Habre called it the "one silver lining" in the coronavirus pandemic. The cleaner air could help those advocating action about climate change because people are now experiencing and appreciating the value of clean air, she said.

"I hope that’s the benefit that comes out of this," the professor said.

Last week, Citymapper, a public transport and journey-planning app, launched its "Citymapper Mobility Index," a data feed that has shown how journeys within major cities of the world have been reduced since stay-at-home orders were invoked across the globe.

Three weeks ago, for example, London was operating at 83 percent. Monday, that percentage dropped to 10. Barcelona, Spain, one of the countries hardest hit by COVID-19, went from 61 percent mobility three weeks ago to 4 percent on Monday, tied for the lowest in the world.

In the United States, on the same three-week mobility comparison, San Francisco dropped from 57 to 8; Boston from 64 to 6; and in New York City from 67 to 8. Mobility in Los Angeles dropped from 71 percent to 12.

It shows up with less truck traffic in the Ports of Los Angeles, less jets at Los Angeles International Airport and empty freeways and roads as residents comply with orders to stay at home.

Bill Magavern, policy director for the Coalition for Clean Air, said the pandemic "is not the way we want to reduce air pollution," but there’s no doubt a major reduction in traffic results in less emissions.

Air quality experts cannot fully give credit to the shutdown. Significant days of rain and breezy conditions in Los Angeles helped to clean out pollution, and typically the air is cleaner during the spring.

"But," Magavern said. "We also are seeing the benefits of reduced traffic and it’s a good reminder that in California, over 80 percent of our air pollution comes from the transport of people and goods."

Bradley Whitaker, a spokesman for the AQMD, said the rain has made it difficult to provide an exact reason why the air is cleaner.

"Air quality has been very good over the last few weeks, but weather tends to be the most important factor impacting air quality," Whitaker said. "The recent increases in rainfall and stormy weather make it difficult to differentiate the impact of the weather from the reduction in mobile source emissions due to the COVID-19 Stay at Home Order."

The AQMD cannot, Whitaker said, reach any definitive conclusions right now, but expects to know more in the coming days and weeks.

"With residents increasingly staying at home, there has been a reduction in mobile sources on the roads. There also appears to be a slowdown in goods movement through our twin ports," Whitaker said. "In recent days, weather has been reverting to normal conditions, but due to the short-term sample of the data, it is still too early to tell what the overall impact has been."

Denny Schneider, a Westchester resident who serves as president of the Alliance for a Regional Solution to Airport Congestion, said he cannot say he’s noticed a reduction in air pollution from Los Angeles International Airport, but has been able to see the nearby mountains in recent weeks and has experienced a reduction in flights near this neighborhood.

Los Angeles International Airport spokesman Heath Montgomery said that’s true. The airport normally has about 1,900 take offs and arrivals a day. That has dropped to about 1,200 a day with 85 percent fewer passengers.

Habre said the reductions help air quality not only in the immediate area around the airport but in communities downwind. Besides flight reductions and passenger traffic, other operations have declined, including diesel-powered vehicles moving people and supplies.

"We definitely know that LAX is a big contributor in general to ultrafine particles," Habre said. "We've been doing some studies to see what that does to health. We've seen, for example, in a very small, very early study that, if you were to walk downwind of that for a couple of hours, we do see significant inflammation in your blood very shortly afterwards."

Could the stay-at-home order and cleaner air change as a result of the stay-at-home order change the way people go about their lives in the future?  Magavern said he hopes people realize now they can connect remotely, that they don’t need to take so many long-distance rips.

"Instead of taking a plane trip from LA to Sacramento for a meeting, maybe do that by video conference," he said. "Instead of driving from LA to Fresno, do that by a video conference. I do think that when we have to change our behaviors, it shows what is possible."

Although cars may fill out freeways again when the pandemic is over and people return to normal lives, Magavern suggested the transition to electric buses, trucks and cars needs to be accelerated.

"We could have clean air if we electrify transportation and also found ways to reduce the miles that vehicles are traveling," he said.

Despite the clear air, the Trump administration announced it is replacing fuel standards established by President Barack Obama in 2012 with a plan that calls for substantially lower annual increases. The move drew a sharp rebuke from Obama.

Magavern and 19 other leaders in climate and environmental issues, immediately sent a letter to California Gov. Gavin Newsom, Senate President pro tem Toni Atkins and Assembly Speaker Anthony Rendon urging them not to "delay or weaken standards that protect public health, air and climate."

"We urge you to put Californians to work building the infrastructure of the clean energy/sustainable transportation economy that we need," they wrote. "We would welcome an opportunity to discuss a ‘green stimulus’ package that could create jobs while reducing emissions to ensure our communities are resilient in the face of any crisis."