Photographs by Alex Welsh

Michael Gollner studies fire and how it behaves at UC Berkeley’s Fire Research Lab. His research is focused on fires that spread from wildlands to urban areas––work that gives him insights into the fires ravaging Pacific Palisades, Altadena, and other areas near Los Angeles. On Friday, I interviewed him about the fires and how to rebuild the communities they’ve destroyed in a way that makes them more resilient. What follows is an edited version of our conversation.

Conor Friedersdorf: How relevant is the debate about how to manage forests––whether to thin them out, for example––to fires like the ones in greater Los Angeles that began in dry sagebrush and chaparral?

Michael Gollner: When extreme wind events occur, one variable is how much fuel is around to burn. Southern California had a lot of rain in the past couple of years, which caused a lot of plant growth, but no rain so far this winter, so that fuel was dry. We’re not talking about big trees burning in a forest. This was mostly little leaves and twigs, things less than a quarter-inch thick, so they get dry pretty quick. I’m not a fire ecologist, but in my observation of fire ecology, I think there’s still some debate on the best way to handle prescribed-burning regimes and fuel management in chaparral ecosystems. What I like to emphasize is: What happens when that fire gets to a community?

To improve protection, we’re not talking about clearing whole forests or bulldozing hills. We’re talking about just hundreds of feet out from the community. We’re talking about giving space between the fire and the community and then making it so that the only thing that can get through is embers.

Embers are little burning particles that are smoldering almost like charcoal when it is not making a flame but is red and glowing. They can loft up in the air and get carried by the wind—some firefighters reported seeing those embers lighting fires two to three miles ahead of the main flame front. You want to harden the community so that those embers are unlikely to light new fires.

[Read: The particular horror of the Los Angeles wildfires]

Friedersdorf: Even knowing that embers start new fires, a part of me can’t comprehend it: I think of struggling to light a campfire even while holding a constant open flame against firewood.

Where is my intuition going astray?

Gollner: It’s partly a matter of scale and probabilities. Any individual ember is unlikely to start a new fire. But a wildfire produces millions of embers. You can see them flying everywhere. One that catches is enough.

And you don’t see an ember land on a big flat surface, like a piece of plywood, and set it on fire. It rolls away. But where? In wind, embers tend to pile up together in one place, like between the boards of a deck, or in crevices at the base of a wall, in front of siding. They can get in nooks and crannies on the roof and pile up there, or if you have a vent, they can fly in through it and land on flammable material. A mulch pile can be a perfect cavity, where an ember or embers settle in a little one-inch area that is protected from the wind enough to smolder and ignite. That’s not something you can model at scale, but you can re-create it in a laboratory.

Alex Welsh for The Atlantic

Friedersdorf: What should homeowners understand about the science of how best to protect their homes?

Gollner: There’s never going to be 100 percent protection. But a shift in preparation can make a big difference, especially a community-wide shift. Firefighters can then have the upper hand and catch those fires that slip through the cracks. I’ve watched the videos of Pacific Palisades and elsewhere. In many places, vegetation management was not taking place. It’s hard to assign fault, because it’s a mix of private, city, county, and state property. But there was lots of brush, trees over structures, people who put juniper bushes next to their house, all in areas we’ve long known to be high-hazard. It’s devastating that it occurred in this way. We never expected it all to come together at once on any particular day. But we knew something like this could happen.

Think of having a defensible space around the home. You don’t want any material there that can catch fire and spread to your house, especially in the five feet around the base of the structure.

And then you want to harden the house against embers. Shake roofs are the absolute worst. The 1991 Tunnel Fire in Oakland Hills raced through wooden cedar-shake roofs, but those aren’t so common anymore. Now it’s flammable siding, flammable decks, open vents without mesh to protect against embers.

[Read: When the flames come for you]

And it’s tempting to think, I did my roof, I did my siding, and I did my vents. But I really love that juniper outside of my window. Well, if that juniper catches on fire, it is going to produce 15-foot-tall flames. It does not matter how strong your windows are; that’s going to shatter them and spread inside.

There is a story from a former fire chief about a house that was built mostly of glass and steel. It was super well defended against embers. Except it had an opening to an interior courtyard where they could land. An ember probably lit a planter on fire, which then probably shattered the glass and moved inside. Otherwise it would have been safe. But they had an opening that kind of let it in. You can build a whole concrete structure and then leave your window open, and it’s lost. So I don’t think the solution is to rebuild everything out of steel or concrete or mud, but rather to thoughtfully build and make sure you have the thought process of sealing the outside of your house from embers and keeping space around it free of flammable materials.

Left to right: Paint bubbles on the exterior of a home, palm trees singed by the Palisades Fire, and the remnants of a burned home in Pacific Palisades (Alex Welsh for The Atlantic)

Friedersdorf: And hope that your neighbors do the same?

Gollner: Yes. You can completely protect your house from embers, and then if you’re close to your neighbor who hasn’t done anything, and their house catches fire, those flames will be so huge, there’s just nothing you can do. You need the whole community to start making changes. If everyone’s making a lot of changes, even short of perfection, you start to see bigger impacts. Still, even if you’re the only one hardening your house, there can be benefits, depending on the fire. For example, over time, more firefighters arrive at the scene of a fire in a given area. When deciding where to focus, firefighters will probably pick houses that seem most defensible, which gives you a better chance. You want to be the house that they feel safe defending, not the house down a long drive surrounded by juniper trees where they feel unsafe.

If you and all your neighbors harden your homes, it’s harder for embers to start and spread fires, and the fire department can put out the isolated fires and save the community. But yes, once embers get into a community and set one house on fire, that fire can jump to the house of the neighbors. Fire spreads fast through vegetation, and slows down when it gets to houses. But houses burn really intensely and for a very long time. The fire dynamics completely change. You see just how much water firefighters are trying to use on house fires. Burning at that intensity, water doesn’t have much impact. So you want some space between your house and your neighbor: 30 feet is an estimate that we’re trying to refine with current experiments.

[Read: The unfightable fire]

Friedersdorf: So in Pacific Palisades, where the entire community burned, it’s unlikely that one home, having been diligently hardened, would have survived, whereas if the whole neighborhood had been hardened against fire, there might have been a different outcome?

Gollner: Right.

Friedersdorf: In communities that have largely or totally burned to the ground, and so have the opportunity to make changes at scale when rebuilding, what changes pass the cost-benefit test?

Gollner: There’s some discussion of trying to move around the footprint of where we build different things. And often that’s near-impossible because people own that land and they’re going to rebuild.

California does have fairly good fire-prevention measures and requirements in its building codes. One of the most important things is to make sure that those are enforced in rebuilding. Make sure that structures are up to code and hard to ignite, and that yards have defensible space and aren’t going to become infernos.

One hopes that if you do that at scale, you can discount some of the design aspects of building resilience into properties and landscaping, so that it’s cheaper for everyone. We’ve seen things like wooden fences spread fire. And so in the five feet next to the house, use metal or a nonflammable material or change the entire fence. There’s a lot of ways that you can make changes. And because of the wealth in Pacific Palisades, I could imagine it becoming a model for rebuilding resiliently. Hopefully this can become an area where, in a future wildfire, people evacuate and no houses burn down, or one house burns without spreading.

Alex Welsh for The Atlantic

[Read: Altadena after the fire]

Friedersdorf: I notice that whereas the public seems focused on city officials better responding to house fires once they start, you’re mostly focused on better preempting house fires from starting.

Gollner: We are never going to stop wildfires driven by extreme winds. But we can prevent large-scale disasters if we understand that almost everything you can do to avoid the worst outcomes must take place long before that first spark. It’s about the way we design our communities, the vegetation around them, the buildings and the way you prepare for the first response, so that you can very quickly identify a fire when it’s so small that a water drop from a plane can put it out, especially if the weather is favorable. Once the fire is large, it’s almost impossible to do anything.

Of course you want to answer questions, like Did the water pressure fail in Los Angeles? and Was the fire department appropriately funded? Investigations may reveal mistakes or a need for reforms.

But when assigning blame, remember, Pacific Palisades was designed 50 to 100 years ago, in a really high-fire-risk area where people built homes without consideration of wildfires. There were mistakes made, mistakes like the difficulty of evacuating, long before we fully recognized that they were going to be mistakes. We’ve allowed them to stand and failed to make commonsense changes. And everyone involved in many decades of decisions is partially responsible.

[Read: How well-intentioned policies fueled L.A.’s fires]

Friedersdorf: How do you study something as chaotic and variable as wildfires spreading into communities?

Gollner: One thing we do is modeling. There’s been a big development there: We took models of how wildfires spread through vegetation and expanded them to include how those fires spread into urban areas: how embers get into communities, how different structures burn, how fires hopscotch between homes and vegetation.

We also do experiments. We go to the Missoula Fire Lab a lot to better understand wildfires. And we go to the Insurance Institute for Business & Home Safety, where they burn tiny houses, or ADUs, in a six-story-tall wind tunnel. We measure heat fluxes. We study how far structures need to be spaced from one another. We collect the smoke to understand what’s in it. We ask questions: How do embers ignite different materials, like mulch or siding or wood? There are still a lot of aspects of how fire spreads that we could understand much better.

About 100,000 scores by the Austrian-American composer have been lost in the Pacific Palisade fires.

Almost 1,000 US prisoners have been fighting the Los Angeles fires for pay as little as roughly a dollar a day.

The wildfires raging through Los Angeles are the most destructive and likely the deadliest in the county's history.

The Rams, Lakers and Clippers all dedicated their games to the community and first responders amid the LA wildfires.

The Los Angeles Rams pay tribute to the city's firefighters and first responders as they clinch the last spot in week two of the NFL play-offs.

This is an edition of The Atlantic Daily, a newsletter that guides you through the biggest stories of the day, helps you discover new ideas, and recommends the best in culture. Sign up for it here.

Over the next several days, many of Donald Trump’s Cabinet selections will appear before the Senate for confirmation hearings. By putting forth a series of unqualified candidates who, in other political moments, would likely not have made it this far, Trump has muddled the process before the hearings have even begun: As my colleague David Graham put it in November, “the sheer quantity of individually troubling nominees might actually make it harder for the Senate to block any of them.”

But the outcome of the Senate confirmation hearings is not a foregone conclusion. Yes, Senate Republicans have shown that they are reliably deferential toward Trump (though some drew a line at his selection of Matt Gaetz for attorney general). Many of his picks will be easily confirmed, my colleague Russell Berman, who covers politics, predicted, given the Republicans’ 53–47 majority in the Senate. But with the current makeup of the Senate, each pick can afford to lose only three GOP votes (assuming that every Democrat opposes the nomination), so for the ones who have yet to lock in support from every single Republican, the hearings could make the difference. Democrats, Russell explained to me, will attempt to use the hearings to build a case for the public that some of Trump’s nominees “are either unqualified or don’t reflect the views and values of most Americans.”

Among the first hearings is one that will reveal whether even a few Republicans are willing to defy the president-elect. Tomorrow morning at 9:30 a.m. EST, Pete Hegseth, a former Fox News host and Trump’s nominee to lead the Department of Defense, is scheduled to appear before senators. They will have much to ask him about, including Hegseth’s confirmation that he reached a financial settlement with a woman who accused him of sexual assault (though he has denied the assault allegation), accusations that he is prone to excessive drinking (he has denied having a drinking problem, and one Republican senator has claimed that Hegseth told senators that he has stopped drinking and won’t drink if confirmed), reports of his failures in leading veterans’ organizations and forced departures from those roles (which Hegseth’s camp called “outlandish claims”), and his suggestion that women shouldn’t serve in military-combat positions.

Democrats have already hammered him on these issues: Senator Elizabeth Warren released a scalding 33-page letter last week outlining questions about his fitness to serve. Republicans have also scrutinized Hegseth and other nominees, although none has yet said publicly that they would vote against any of Trump’s picks. Russell advised that in addition to the Republican moderates Senators Lisa Murkowski and Susan Collins, GOP senators to keep a close eye on throughout the hearings include Senator Mitch McConnell, who is somewhat liberated from total deference to Trump because he’s no longer leader of the party, and Senator Bill Cassidy of Louisiana, who voted to impeach Trump after January 6.

Not every pick has a hearing scheduled yet—RFK Jr., Kash Patel, Tulsi Gabbard, and others are not yet on the calendar. In recent decades, just one Cabinet nomination (John Tower, George H. W. Bush’s pick for secretary of defense) has been voted down; others who faced tough odds have withdrawn—a path Hegseth or other nominees may follow if it seems likely they won’t win enough support. Gaetz, Trump’s initial pick to lead the Justice Department, bowed out shortly after being tapped, following an ethics-committee inquiry into allegations that included sexual misconduct and illicit drug use (Gaetz has denied any wrongdoing).

Senators from both parties have pushed to see FBI background checks that, although not legally required, have been customary for a president to mandate (the agreement that Trump’s transition team signed with the DOJ did not specify whether he will require FBI involvement for his picks). Trump and his supporters have for years been attempting to damage the reputation of the FBI, and now some, including Elon Musk, are suggesting that anything the agency digs up won’t be credible. That posture, Russell explained, is another tactic to “speed up the confirmation of nominees whom the Senate might have rejected in an earlier political era.” In an effort to get their way, Trump’s allies seem poised to cast doubt on the whole process, encouraging Americans to mistrust another long-standing government norm. That legacy could last longer than Trump’s second term.

Related:

Donald Trump’s most dangerous Cabinet pick The perverse logic of Trump’s nomination circus

Here are four new stories from The Atlantic:

Maybe it was never about the factory jobs. Should you be prepping for Trump? A wider war has already started in Europe. How the ski business got too big for its boots

Today’s News

Winds are expected to pick up across parts of Los Angeles and Ventura counties, according to the National Weather Service. The wildfires in Southern California have killed at least 25 people, according to the Los Angeles Times. Federal Judge Aileen Cannon allowed the release of a portion of a report written by former Special Counsel Jack Smith about the 2020 election-interference case against Trump. President Joe Biden announced that student loans will be forgiven for more than 150,000 borrowers.

Dispatches

The Wonder Reader: Everyday decisions can accumulate into a life of isolation, Isabel Fattal writes.

Explore all of our newsletters here.

Evening Read

Illustration by Leon Edler

The Easiest Way to Keep Your Friends

By Serena Dai

The hardest part about adult friendship is, by far, scheduling time to see one another, especially when trying to plan for a group. Thursday’s bad for one person, and Saturday’s not good for another. Monday would work—but hold up, the restaurant we want to try isn’t open that day. Let’s wait a couple of weeks. Somehow, though, the day never comes. Your friends forgot to follow up, or maybe you did. Either way, can you even call one another friends anymore?

Read the full article.

More From The Atlantic

Not just sober-curious, but neo-temperate How well-intentioned policies fueled L.A.’s fires A novel that performs an incomplete resurrection Reckless driving isn’t just a design problem.

Culture Break

Illustration by The Atlantic

Explore. Strange turns of phrase online—“he’s so me for this,” “if you even care”—have seeped into daily life. A going theory about the cause is that people have gotten stupider, Kaitlyn Tiffany writes. But maybe this isn’t true.

Read. In her debut novel, Too Soon, Betty Shamieh isn’t trying to educate or enlighten, Gal Beckerman writes. She’s telling a Palestinian story unlike any other.

Play our daily crossword.

Stephanie Bai contributed to this newsletter.

When you buy a book using a link in this newsletter, we receive a commission. Thank you for supporting The Atlantic.