Science

Downwind From the Fires

My town was spared by the infernos tearing through Southern California. We’re still in danger.

The sky is not supposed to look like this at 3:20 p.m.
The sky is not supposed to look like this at 3:20 p.m.

Will Oremus

GOLETA, California—The sky is cloudless here, yet the sun shines dimly through a gray haze tinged with queasy shades of orange and pink. Flecks of ash drift aimlessly down and settle to form a thin layer on plants, cars, and the ground. The air outside tickles your nose and eyes, and wherever you go, it smells like you’re standing next to a bonfire. In many homes, it’s noticeably smoky even indoors. Local hardware stores are sold out of air purifiers.

As wildfires tear through Southern California, devouring homes and forcing evacuations, the danger to those who live and work in their direct path could hardly be clearer. But there’s another group of people who are feeling the fires’ effects in a subtler way—and their health is at risk in ways they may not fully understand.

I live near Santa Barbara, some 20 miles up the coast from the Thomas fire’s northern edge, as of Thursday afternoon. Most of the time, it’s paradise. And its residents feel fortunate even now, as it appears unlikely the fire will reach this far. The University of California–Santa Barbara has opened a shelter for evacuees from Ventura County. People feel relatively safe here.

But maybe they shouldn’t. For a combination of reasons having to do with topography and wind patterns, the smoke from the Thomas fire appears to have picked Santa Barbara and its environs as a place to settle. The result is that this sun-kissed city of 90,000—typically blessed with fresh maritime air—is experiencing its unhealthiest air quality in memory, with conditions comparable to some of the worst days in hyperpolluted Beijing. One difference is that this city and its residents are far less prepared.

People understand that when a fire is coming, they could die. But the risks posed by bad air quality are, well, murkier. Murkier still is what to do about it, and how Western cities like Santa Barbara—which may face more frequent forest fires in the future due to climate change—ought to prepare and keep their residents safe.

The Environmental Protection Agency considers an Air Quality Index of 100 or above to pose health risks. As of 1 p.m. PT on Thursday, Santa Barbara’s AQI for small particulates had climbed to 363—by far the worst in the country, according to the EPA site Airnow.gov, and well into the maroon “hazardous” range, which is the most severe on its color-coded AQI chart. That’s higher even than the AQI in places like Ojai and Ventura that are actually on fire. It means that even perfectly healthy adults might suffer some effects, while those in vulnerable groups—small children, the elderly, and those with lung or heart conditions—could face serious risks. It’s close to the 400-plus AQI that Napa experienced during the fires there in October, and far worse than what the rest of the Bay Area saw.

Lyz Hoffman, spokeswoman for the Santa Barbara Air Pollution Control District, said she’s never seen anything like it here. Since the county began measuring AQI for fine particulate matter (known as PM 2.5) in 1999, the highest index on record was 124 in Santa Maria in 2001.* There was no predicting it before Thursday. And there’s no indication that it will improve Friday.

When the AQI is in the “unhealthy” or even “very unhealthy” range for a short time, recommendations are relatively straightforward: Stay indoors when possible and consider buying an air purifier. If you must go outside, consider wearing a special type of respiration mask (normal surgical masks won’t help). But in the “hazardous” realm for an extended period, there’s not a whole lot you can do. And what exactly might happen to you isn’t fully clear.

“We’re getting a lot of calls from people who are saying they’re experiencing smoke now inside their houses, or the smell of smoke,” Hoffman told me. “So that’s a concern because we’re advising people to stay indoors as much as possible. But If you can’t keep your indoors clean, it’s not going to be safe for you indoors either.” In that case, she said, her best advice would be for those vulnerable to air pollution to pack up and go somewhere else, if they can, until conditions improve.

The air quality district and public health departments took what precautions what they could Thursday, putting out press releases announcing the danger and setting up stations where people could come and pick up masks. But there was no mobile alert about air quality comparable to the ones sent about the fires themselves.

By Thursday afternoon, many of my neighbors made plans to leave town—and my family is doing the same. But as we pack up, it’s hard not to think about the many other folks who are still planning to work tomorrow, and who will sleep tonight in smoky homes. Not to mention all those sheltering in Santa Barbara as a refuge from the fires farther south.

Nothing Santa Barbara is going through compares to what those in and fleeing Ventura, Santa Paula, or Ojai are experiencing right now. Still, the situation here should worry public health officials and others planning for future wildfires, once the blazes are under control. (And, of course, the threat of wildfires is not confined to California. A 2016 study in the Proceedings of the National Academy of Sciences found that the area of the United States that’s subject to forest fires has doubled since 1984, and is likely to keep growing.)

When fires menace major cities, such as Los Angeles, local and state officials pour all their resources into protecting population centers. But there’s no stopping the wind—and if it were blowing the other way, it could be 13 million Angelenos at risk instead of 90,000 Santa Barbarans.

*Correction, Dec. 8, 2017: This article originally misstated that Santa Barbara County began measuring an Air Quality Index in 1999. It has been measuring an AQI for fine particulate matter since 1999, but had been measuring an Air Quality Index earlier. Also, due to an editing error, the headline misstated Santa Barbara was upwind from the fires. It was downwind. (Return.)