Amid pandemic, air quality remains critical environmental challenge

In 2020, the first year of the COVID-19 pandemic, California’s greenhouse gas emissions dropped by almost 9%, and the state’s smoggy skies briefly cleared. This was particularly true during the pandemic’s first months, when schools closed, offices went remote, and statewide shelter-in-place orders kept millions of Californians at home. That spring, clogged freeways went vacant. Fewer semis rattled down roads. Many city streets remained relatively uncluttered as Californians’ cars stayed parked and drives clocked shorter distances.

California has the world’s fifth largest economy, but as the nation’s most populous state, its transportation sector—which includes peoples’ passenger vehicles, planes, along with the ships, trains, and trucks that transport goods—produces most of the state’s air pollution, not industry or power generation.

By killing the commute and slowing the economy, the pandemic temporarily did what policymakers could not: got Californians out of their cars.

“What some people don’t realize is that goods movement is actually the biggest cause of air pollution in California,” Bill Magavern, the Coalition for Clean Air’s Policy Director, told me. “Almost all of the equipment that moves goods right now is powered by diesel—that includes trucks and locomotives, even a lot of cargo-handling equipment—and diesel exhaust is a huge toxic contributor to both smog and soot, which are the pollutants whose prevalence and impact on human health we worry about the most.”

By killing the commute and slowing the economy, the pandemic temporarily did what policymakers could not: got Californians out of their cars.

According to the California Air Resources Board, Californians drove their small passenger cars 44% fewer miles in April 2020 than they did in April 2019. State Department of Transportation data from April 5, 2020 measured a 51% decrease in average traffic volumes, compared to April 2019. During all of 2020, transportation sector emissions dropped 16%, but in April 2020 specifically, emissions from California’s transportation sector had fallen by one-fifth because of the pandemic. The results were acute.

In April 2020, the Los Angeles Basin experienced the longest period of clean air days since 1995, and that metro area contains 15 of the nation’s 25 cities with the most polluted air. Professor Yifang Zhu at the UCLA Fielding School of Public Health reported that levels of the hazardous airborne particulate matter known as PM2.5 fell in the L.A. Basin from 16 micrograms per cubic meter to 12 immediately after stay-at-home orders took effect.

“Initially, COVID caused traffic to drop significantly, but that also coincided with the late winter-early spring season, which is a time when weather typically improves air quality…” — Bill Magavern

“In a sunny place like Los Angeles, where mountains hold stagnant air in place,” Magavern told me, “summer heat and light essentially cook volatile organic compounds and oxides of nitrogen, or NOx, into the chemical stew that we call smog. In the wintertime, the pollutant of concern is fine particulate matter, known as PM2.5. This is very hazardous to human health, because it gets into the bloodstream and lungs, where it can cause a range of health issues, including lung cancer, pulmonary disease, heart disease, stroke, and premature death. Smog is usually our worst summertime issue. Particulate matter is often worse in winter, when cold air gets trapped in the lower atmosphere and just stays there. If you go a long period without rain, as we’ve often had in these drought periods, then the particles stick around even longer.”

Here’s where the story of California’s 2020 air quality gets complicated.

“Initially, COVID caused traffic to drop significantly,” Magavern told me, “but that also coincided with the late winter-early spring season, which is a time when weather typically improves air quality, so it’s a little hard to separate these factors.”

Much of California has a Mediterranean climate, defined by dry warm summers and wet cool winters. Rain washes the particulate matter out of the air, and wind breaks up the stagnant air and moves it out of wherever it is trapped. So while changes in driving habits and what’s called ‘goods movement’ were lessening emissions in the spring of 2020, rain and windy weather also contributed to some of the state’s improved air quality back then, before the shelter-in-place orders did. Of course, the role human activities play in creating air pollution cannot be ignored any more than the pandemic’s brief, drastic reduction in driving contributed to cleaner air.

The blue skies wouldn’t last.

The pandemic didn’t solve anything. It only showed Californians the quality of air they should be breathing.

“Shortly after that air quality improvement,” Magavern said, “truck traffic picked up again big time. Even though people may have been driving less during the early part of the pandemic, they started ordering a lot of goods. Whether it was stocking up on food and toilet paper, or adding office and exercise equipment to their homes, because they were home so much, goods movement increased, and that increased air pollution along the whole supply chain, from big ocean-going vessels, container ships stacking up off the ports of Los Angeles and Long Beach, down to the freight carried on rails and roads.”

As pandemic restrictions relaxed and restless, locked-down Californians also got back in their cars, demand for fuel processing returned, and so did emissions. After that brief 44% reduction of commuter miles, California motorists now drive as many miles as they had before the pandemic.

Viewed from the proverbial rearview mirror, the state’s temporary pandemic reductions in emissions of 2020 resemble the anomaly that they were — what statisticians would classify as an outlier—because the skies grew hazy again. The pandemic didn’t solve anything. It only showed Californians the quality of air they should be breathing.

The pandemic also showed with absolute clarity that if you can get drivers to burn less fuel, air quality will improve. Unfortunately, 2020 also show that emission reduction efforts only matter if the landscape isn’t also burning. California’s air quality remains some of the worst in the world. The new reason: wildfire.

Wildfire and air quality
 While the pandemic created an unprecedented change in driver behavior, climate change inflicted blazes of historic significance, making 2020 California’s worst wildfire year and extreme wildfire the norm.

“If you’re wondering, are we on track for our [climate] goals? How are things looking? It was an anomalous year.” — Danny Cullenward

In 2020, the pandemic reduced driving in California so dramatically that the state experienced a reduction of 35 million metric tons of carbon dioxide emissions, according to the Air Resources Board. Unfortunately, UCLA researchers discovered data that the 2020 wildfires released 127 million metric tons of carbon dioxide into the atmosphere, negating two decades worth of emission reduction efforts and the Board’s much-publicized emission reduction statistics.

These two emission phenomena—from COVID and wildfire—occurred simultaneously, but statistically, only the fires matter, because they keep occurring. COVID’s effect was fleeting. California’s transportation sector is still the state’s main source of greenhouse gas emissions, but the 2020 wildfires became the state’s second largest source of greenhouse gases. “And those were caused by a combination of climate change and poor forest management,” Magaven said.

“The whole issue is what happens after the pandemic year,” Danny Cullenward, policy director of the California nonprofit CarbonPlan, told The Los Angeles Times. “If you’re wondering, are we on track for our [climate] goals? How are things looking? It was an anomalous year. There’s nothing surprising in the data released. It was not a very representative year. What matters is what happens as we came out of it.”

We came out of the pandemic. So what new approaches and policy have come out of it?

Forest health, air quality, and climate change
California has quickly made itself into a world leader in the effort to reduce greenhouse gas emissions. It aims to be carbon neutral by 2045, through an ambitious combination of green energy, green buildings, reduced in-state petroleum production, infrastructure advancements, and replacing gas-powered vehicles with electric vehicles. Yet creating some of the world’s most stringent targets for greenhouse gas reductions has not protected it from its own highly flammable forests.

Through a mixture of forest management practices and climate change, California’s forests have burned more frequently in recent years.

Home to a high number of endemic species, California is a global biodiversity hotspot. Its staggering array of native ecosystems range from sequoia forests to cypress forests, deserts to coastal sage scrub, and they contain some of the world’s oldest, largest, and tallest trees. Many of its habitats are also very flammable, due to everything from naturally combustible manzanita bushes whose seeds need fire to open to unnaturally dense stands of young conifers, thick understory layers of fallen leaves and dry plant debris caused by the Forest Service’s historic approach of fire suppression. Through a mixture of forest management practices and climate change, California’s forests have burned more frequently in recent years.

2020 was the state’s worst fire season, marked by five of the 10 largest wildfires in state history, as well as its largest single fire, the August Complex fire, which burned over 1 million acres. In 2020, over 8,100 wildfires burned in California, across nearly 4 million acres, killing 26 people and destroying approximately 7,000 structures.

Fires burned fewer acres in 2021, but that fire season was still severe. 2021 included California’s second largest fire in history, the Dixie fire. The state’s wildfire season started earlier and ended later than usual, driven by reduced winter snowpack and earlier snowmelt from a warmer spring and summer.

“Where smog is California’s summer issue and PM2.5 is its wintertime pollutant of concern,” said Magavern, “wildfires change that equation, because fires put a lot of particulate matter into the air, and fires are typically the worst in late summer and early fall, which are, of course, times when California gets very little rainfall.”

“Wildfires in the western U.S. are not only increasing the number of days and places with unhealthy levels of particle pollution. They are also increasing the severity of pollution.” — American Lung Association

Forests both store carbon dioxide and emit carbon dioxide, depending on their state. Standing, living forests are carbon banks. By turning sunlight into energy through photosynthesis, forests sequester CO2, pulling it from the atmosphere and storing it in their trunks, branches, roots, soil, and leaves. When forests burn, they release stored carbon into the atmosphere. California’s 2020 fires contributed to the state’s air quality rating as some of the worst in the world at times. Catastrophic wildfires create consecutive days of smoke in California, which contains harmful chemicals that people should not be breathing.

This spring, The American Lung Association released its 2022 State of the Air report, which examines the regions suffering from the worst air quality, and the American West rates high on the list. “Wildfires in the western U.S. are not only increasing the number of days and places with unhealthy levels of particle pollution. They are also increasing the severity of pollution,” the Lung report says.

Without dissecting whether forest mismanagement or climate change is more responsible for the situation, what is clear is that the state’s weather is changing, and that change is extending California’s wildfire season and making it more severe. What’s also clear is that proper forest mismanagement can reduce fuel loads and reduce fire’s frequency and severity, so forest management has to be part of climate change and air quality policies.

After the last two catastrophic fire seasons, the connection between healthy forests, healthy air, and climate changes is so profoundly obvious that Magavern sees numerous policymakers and public officials engaging this complex of factors.

The federal government owns approximately 58% of California’s 33 million forest acres. California owns 3% of its forests.

“I would say that the Natural Resources Agency in California very much recognizes forest management as an important factor here in air quality,” Magavern told me. “I think they know what the solutions are, they’ve just been kind of slow to implement the solutions, in terms of getting enough of the forest treated. Of course, because a lot of our forests in California are on federal lands, we rely on the federal government for management and fire prevention.”

The federal government owns approximately 58% of California’s 33 million forest acres. California owns 3% of its forests. Indigenous communities, corporations, and private interests own the rest. What that means is that California depends on the federal U.S. Forest Service and Bureau of Land Management to manage the bulk of the forest and scrub lands where California’s fires burn, and that federal agencies are responsible for reducing those fires and the air pollution they cause.

It’s important to note that, despite the term “forest fire,” what is more accurately called “wildfire” in the West does not burn in forests at all. It burns on treeless scrubland, such as in chaparral, especially in southern California.

“We also need to understand that a long historical period of intense fire suppression was a big mistake,” said Magavern, “because it allowed a lot of flammable material—fuel—to buildup and create the conditions that are causing catastrophic wildfires now, along with climate change.”

Forest health and wildfire play in climate change now have to play significantly into California’s carbon neutrality goals and policy efforts, because converting gas-powered vehicles to electric, and using green building design to reduce greenhouse gasses, will be less effective if future fires negate these efforts.

State and federal agencies must thin and clear many of California’s forest types to reduce the fuel loads that turn low-intensity fires into the hot crown fires that turn the ecological clock back hundreds of years, and to curb the sprawling blazes that decimate entire communities. Thinning is not the same as logging. Thinning reduces the density of vegetation. It does not harvest old trees for timber. Stands of mature and old-growth trees need to be kept in place and protected, but fuel loads in flammable forest types, as well as scrublands like chaparral, must be reduced to prevent massive, high-intensity burns.

“But one of the problems for implementation is lack of funding. ” — Bill Magavern

Although he is an air quality expert, not a forestry expert, Magavern sees California policymakers and public officials increasingly recognizing the important connection between healthy forests and carbon emissions.

“We are working with other state agencies on ways to stabilize forests and return them to sustainability as carbon sinks,” California Air Resources Board spokesperson David Clegern told The Los Angeles Times this fall. “In the meantime, it is essential that we work even harder to reduce fossil fuel emissions as it is clear that they are driving the overall problem and we have the means to make those reductions now.”

In California, The Air Resources Board carries much of the responsibility for planning climate change policy. They work with the numerous agencies and are currently working on their five-year plan for climate change, called The Scoping Plan. It includes a robust section on natural lands and working lands. Whatever the Plan’s strengths or flaws, Magavern sees it and other policy as a very serious acknowledgement of the scale of California’s climate problem, and serious efforts to create solutions. “But one of the problems for implementation is lack of funding,” he said.

In a dark way, the polluted skies and excessive wildfire smoke have shown California voters how important forest management and air pollution policy is.

Magavern, environmental allies, the state Democratic Party, the ride-hailing company Lyft (which largely bankrolled the measure) and others backed Proposition 3o, which would have raised billions of dollars by levying an additional tax on people who earn more than $2 million a year. Among other things, the money would have been used to clean up transportation emissions and to control and prevent wildfires.

The measure was rejected earlier this month, following opposition from Gov. Gavin Newsom and the California Teachers Association.

If the last two years have shown us anything, it’s that if you can get people to use less fossil fuel, then air quality will improve, but that only matters if the landscape isn’t also burning.

In a dark way, the polluted skies and excessive wildfire smoke have shown California voters how important forest management and air pollution policy is.

“Healthy air is a topic that’s popular with voters,” Magavern told me. “Californians can see climate change happening now in their own lives, and every fire season makes the fight for clean air even more compelling.”

This isn’t some niche interest. It isn’t an abstract concern for scientists. Treating forests as carbon banks is everyone’s concern now. Just look up. A dark plume of smoke may be billowing from the horizon, or maybe a thick brown haze is obscuring the sun. Ash might rain down on your yard one day. You might even be able to taste it.