The Challenge of Air Pollution
Southern California’s notorious air pollution has been cleaned up dramatically over the last few decades, but the region’s air is still among the worst in the country — with no real plan to reign in the most noxious emissions. How can LA put our smoggy days behind us for good?
The archival images of a smog-laden Los Angeles offer a shocking window into the past. The buildings of downtown LA are barely visible from City Hall a few blocks away. Residents teary-eyed, protecting faces with handkerchiefs, or sometimes even wearing gas masks, stand on streets shrouded in haze.
Over the last half-century LA shrugged off its smoggy stereotypes and — with a nudge from federal regulations — achieved much clearer skies. But those bad air days aren’t history just yet. In the last few years, LA’s somewhat improved air quality has worsened once again, erasing the decades of gains that the region had made to keep deadly pollutants from being pumped into the atmosphere. And while pollution adversely affects everyone in the region, from shouldering excess healthcare costs to the economic burden of missing school and work, LA’s bad air quality has greatly exacerbated existing public health disparities — creating a widening chasm between the Angelenos who have access to clean air and those who simply don’t.
When those infamous smog shots were taken in the 1940s, scientists didn’t yet know what caused the phenomenon. During one particularly bad smog event during World War II, officials worried that the city was under a chemical attack. In a way, it was — but the enemy wasn’t an invading army, it was parked in every LA garage. The evidence is now conclusive: the burning of fossil fuels not only spews a wide range of noxious gasses and particulate matter into the air we breathe, when those same pollutants react with sunlight — regardless of whether they’re incinerated or evaporated — they create a particularly bad compound known as ground-level ozone. (Not to be confused with stratospheric ozone, high in the atmosphere, that keeps the planet from overheating.)
On calm, warm days in a city swarming with internal combustion engines, ground-level ozone settles over the region like a toxic blanket. Not ideal for a place with over 300 days of sunshine a year.
The Clean Air Act, passed in 1970, required states to adhere to new federal air quality standards. It also gave California powerful tools to combat its smog problem. The state now requires drivers to undergo regular smog testing, outfits commercial vehicles with toxin-grabbing “scrubbers,” and sets its own emissions standards for new passenger cars and trucks sold in the state. The air got considerably better. But it’s still not considered “good.” The Environmental Protection Agency (EPA) deems air “unhealthy” when concentrations of pollutants exceed acceptable levels; in recent years, wildfire-weary Angelenos have grown familiar with the a version of the indicator, known as the Air Quality Index, or AQI, which measures several airborne pollutants on a color-coded scale ranging from good (green) to unhealthy (orange) to hazardous (dark maroon).
Despite major improvements, LA still has yet to meet the standards for ozone pollution set over 40 years ago. And lately, we’ve started to backslide. In 2020, the South Coast Air Quality Management District (SCAQMD), which monitors and regulates the LA region, registered 157 “unhealthy” days for ozone — a number not recorded since the 1990s. Ozone remains a top concern, but health officials are increasingly sounding the alarm about PM2.5, named for the size of the 2.5-micron particulate matter which can work its way into the bloodstream and is very dangerous for young, elderly, and pregnant people. LA hasn’t met the federal standards for PM2.5 either. Our air still routinely ranks among the worst in the nation, and for two decades the region has received an “F” grade from the American Lung Association.
One in five deaths worldwide are directly attributable to the burning of fossil fuels and cleaner air would save thousands of lives in LA County each year. Breathing dirty air also sentences LA County’s residents to increased risk of respiratory and pulmonary illness, more frequent ER visits, and chronic conditions like asthma and dementia — all of which occur at higher rates in Black and brown communities and low-income neighborhoods, which are also more likely to be located close to freeways, near industrial centers, or sites where fossil fuels are extracted or refined. Although there are both state and local plans to eventually shut down LA County’s oil wells, there is no plan to close oil and gas production or storage sites. And although LA is making steady progress towards its goals to be 100 percent powered by renewable energy like solar and wind by 2035, a majority of our power is supplied by gas-fired plants which, due to concerns about being able to meet peak demand, won’t be taken offline anytime soon.
The quality of the air Angelenos breathe also depends on geography. Due to offshore breezes and cooler temperatures, the air is generally cleaner along the coast — where communities are largely whiter and wealthier — and worse in the valleys, where pollutants are trapped by mountain ranges and subjected to extreme heat. The exception, of course, are the neighborhoods around the Port of Los Angeles, where emissions from idling ships and trucking routes in the largest port system in the western hemisphere are directly correlated to the highest asthma and cancer rates in the region. The neighborhoods along the transportation corridors that lead out of the ports are located in what’s dubbed the “diesel death zone,” tracing a toxic path to the Inland Empire, home to growing numbers of distribution centers for companies like Amazon. High rents and exclusionary zoning forces LA residents to move eastward, into the path of belching semi-trucks, diesel locomotives, and brand-new airports. A housing crisis paired with the country’s online shopping habits are poisoning large swaths of the LA region.
Electrifying LA’s entire goods movement system, from ships to cranes to trucks to delivery vans, is critical to clean LA’s air. The scale is massive for a port complex that processes 40 percent of all U.S. imports. But the port has a plan, and the region is taking strides towards this goal. Cargo ships can now “plug in” to the grid for power when docked, and the Port of LA started imposing a fee on shipping companies that goes to fund electrification pilots for logistics companies. This subsidy is very important because getting drivers into new EV trucks and installing new charging infrastructure is very expensive. Starting in 2021, SCAQMD began requiring warehouses to eliminate or offset their truck pollution or face heavy fines. And while it’s critical to electrify trucks, efforts to move more cargo to electrified rail both eliminates tailpipe emissions and simultaneously alleviates other negative impacts of trucking in nearby neighborhoods, which still have to contend with tire dust, noise, and too-wide dangerous streets. Progress on all those efforts has been incremental but steady.
But LA’s ongoing inability to attain its air quality goals has led to increasing conflict between local and federal agencies about who is responsible for implementing the more drastic change that’s needed.
In 2022, SCAQMD sued the EPA, arguing that the greatest sources of ozone pollution — including the ports and railyards — are under federal, not local, jurisdiction, and LA cannot tackle those sources without more federal help. When pandemic-era supply chain problems caused shipping backups, for example, the feds pressured the ports to switch to 24-hour operations, which caused a spike in emissions.
There’s also a legal fight between SCAQMD and environmental groups over whether the warehouse regulations simply allow deep-pocketed companies to keep polluting. The proposed offsets are ineffective at actually eliminating emissions, many major polluters just pay the fines anyway, and the agency has been slow to collect fees.
Meanwhile, the EPA has been slow to approve a new heavy-duty truck rule that would set nationwide emissions standards and help regulate interstate vehicles. But the EPA holds the upper hand here: if LA continues to fall out of compliance, EPA has the power to introduce sanctions like taking away federal roadway funding.
SCAQMD officials are right that electrifying the entire goods movement system will be costly and complicated. Which is why smog-forming emissions from cars — something that’s fully under local jurisdiction — must be even more dramatically curbed. Even though California is planning for a phase-out of sales of gas-powered cars by 2035 and gas- and diesel- powered trucks by 2036, it will still take decades to fully electrify the fleet. And switching to electric vehicles won’t solve the air pollution problem completely. Although EVs eliminate tailpipe emissions, they still generate brake and tire dust which are leading contributors to PM2.5 pollution. Smaller electric vehicles and electric bikes that allow people to make more trips without cars, including deliveries, would help. There’s also growing support for implementing new tools like congestion pricing which could reduce or permanently restrict polluting vehicles from urban centers. London’s Ultra Low Emission Zone (ULEZ), put in place a decade ago, has dramatically improved the city’s air, partially because the tolls collected fund more infrastructure for walking, biking, and public transportation, which in turn gets even more people out of their cars.
'State climate regulators offer major incentives for public transportation agencies to switch to electric buses, and there’s a lot of money for electric school buses — many of which in LA are, shockingly, still diesel — but regulators should be similarly focused on tools that decrease car use. These are levers that can be pulled by LA agencies with better service and infrastructure — without any help from the feds.
Even if LA takes the necessary steps to eradicate its smog problem, the region will not be immune to other air quality issues caused by a warming world. Wildfires, which are burning longer, more intensely, and much closer to urban residents, pose an increasing risk to air quality, especially when dangerous smoke particles can affect the health of people hundreds of miles away. In addition to standard alerts, air quality regulators now issue warnings to stay inside and limit activity during smoke events. Some Southern California cities are championing a new type of civic resource known as a resilience hub: locally run community spaces that can act as smoke refuge centers, cooling centers, and provide assistance during other types of disasters. The unpredictability of access to healthy air is why it becomes even more essential to invest in mitigation tools like well-insulated buildings, filters, and purifiers, especially in schools. And it’s why powerful labor protections must be put in place for people who work outside.
But even being indoors doesn’t necessarily guarantee the air will be cleaner. Dangerous airborne pollutants also find their way directly into LA homes through gas stoves, found in about 70 percent of all California dwellings. New studies show that gas stoves leak noxious gasses and their use in households has strong correlations with asthma and cancer rates. Many of the region’s cities are passing legislation that will phase out new gas hookups or require old stoves to be replaced with electric and induction ranges. These laws are being bitterly fought by oil and gas companies because maintaining these tiny pipelines into people’s kitchens represents the final stronghold for industries that know their days are numbered in the region. Which is why severing all ties with the fossil fuel industry is the only way to guarantee that LA can breathe easier.
Want to make a difference? It’s crucial to get the South Coast Air Quality Management District involved. Read more about why and how!