You’re out of free articles.
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
Sign In or Create an Account.
By continuing, you agree to the Terms of Service and acknowledge our Privacy Policy
Welcome to Heatmap
Thank you for registering with Heatmap. Climate change is one of the greatest challenges of our lives, a force reshaping our economy, our politics, and our culture. We hope to be your trusted, friendly, and insightful guide to that transformation. Please enjoy your free articles. You can check your profile here .
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Subscribe to get unlimited Access
Hey, you are out of free articles but you are only a few clicks away from full access. Subscribe below and take advantage of our introductory offer.
subscribe to get Unlimited access
Offer for a Heatmap News Unlimited Access subscription; please note that your subscription will renew automatically unless you cancel prior to renewal. Cancellation takes effect at the end of your current billing period. We will let you know in advance of any price changes. Taxes may apply. Offer terms are subject to change.
Create Your Account
Please Enter Your Password
Forgot your password?
Please enter the email address you use for your account so we can send you a link to reset your password:
This summer was hot. It was wet. It was deadly. For most of us, it was a preview of the rest of our lives.
So here we are: Another summer in the books.
After Labor Day, whites go back in the closet; kids go back to school. Astronomically speaking, there are still technically 20 days left of summer, and climatologically speaking, we may have even longer to go than that — summers are getting longer as autumns contract. But culturally, anyway, we’re now headed into fall, an incongruous transition epitomized by the bastardized existence of the iced pumpkin spice latte. You know you’re living in the age of climate change when ...
It’s a good time, though, for taking stock. An astonishing 96% of Americans have faced at least one extreme weather alert from the National Weather Service since May 1, the Union of Concerned Scientists’ Danger Season tracker reports. Further, only seven counties out of 3,224 in the whole country and its territories had no heat, flood, fire, or storm warnings between May 1 and August 29 of this year, according to additional numbers supplied to Heatmap by the UCS — including, surprisingly, San Fransisco County in California, home of what has been called the single-most economically vulnerable major city to climate change in the U.S.
These were the others that dodged extreme weather alerts: Aleutians East Borough (Alaska); Aleutians West Census Area (Alaska); Ketchikan Gateway Borough (Alaska); Kodiak Island Borough (Alaska); and Norton City (Virginia). Together, they have a population of around 39,500 — just a fraction of San Francisco County’s 815,200.
But while San Francisco, some islands and bays in remote regions of Alaska, and a sliver of Virginia got lucky (this time and so far), it was a bad summer to be in Arizona, where there were more NWS extreme weather alerts issued than in any other state. Coconino County, home of the capital of Flagstaff, saw 146 alerts this summer due to a parade of heat, flood, and fire threats, followed closely by Mohave County, in the state’s northwesternmost corner, with a total of 145. New Mexico was right on Arizona’s tail with five counties in the top 10:
When it came to heat alerts specifically, Texas and Puerto Rico dominated the top of the list. In fact, Louisiana’s Sabine Parish was the highest-ranked non-Texan or Puerto Rican county for heat alerts, clocking in way down at #96.
The most flood alerts were experienced by California’s Inyo County, the home of Death Valley, which might be surprising until you remember how little rain it takes to trigger a disaster in the desert. Washington’s Yakima, Kittitas, and Skamania counties lead the list for fire weather alerts; and South Carolina’s Georgetown, Colleton, and Charleston counties lead for storm alerts. (The data was collected just before the brunt of Hurricane Idalia swept through northern Florida, Georgia, and the Carolinas). California’s Los Angeles County, the most populous in the country, faced a total of 80 extreme weather alerts this summer; the average for all counties was around 44.
The UCS Danger Season data (which will continue to be collected here through October) did not account for air quality warnings, which were the main story of the early summer in the U.S. — at times, more than a third of Americans faced degraded AQI due to smoke billowing south from the Canadian wildfires (which are themselves record-breaking). June 7 was the worst day for wildfire smoke exposure in American history “by far,” my colleague Robinson Meyer reported, and it happened not on the West Coast, where fires are routine, but in New York City, Philadelphia, Washington, D.C., and Toronto.
The next month, July, was the hottest month on Earth in probably 120,000 years (so you have that bragging right on about 4,000 or so generations of your ancestors). Some 40,000 different locations around the world recorded their hottest days ever in 2023, with nearly 20,000 of those in the United States, according to NOAA’s records. Though we didn’t break the global heat record this year (Death Valley only reached 128 degrees Fahrenheit, short of the 130 it needed to beat), the planet recorded its warmest day ever a few different times. Meanwhile, Vermont saw catastrophic summer flooding.
Then, in August, a grass fire fueled by hurricane winds ripped through Maui. Even three weeks later, we still don’t know how many people were killed. Undoubtedly, though, it is the deadliest wildfire in modern U.S. history — and all the more shocking for the fact that it burned through a former wetland, a grim testament to the effects of colonialism. America might not be through reckoning with massive fires, either; the peak of fire season is known as “Snaptember” among hot shot crews for a reason.
And summer wasn’t through with us yet. Hilary became the first tropical storm to hit Southern California in 84 years, and while the damage wasn’t too bad, the Los Angeles Times credits the urgency of the early warnings for saving lives. Subsequently, Hurricane Idalia became the first hurricane to make U.S. landfall in what is predicted to be an “above normal” season, strengthening from a Category 1 to a Category 4 storm in 24 hours thanks to record-warm waters in the Gulf of Mexico. Reports of the damage are still trickling in, but it can’t be good news for insurers in Florida and the Southeast.
It is difficult to tie any one weather-related disaster to climate change, but as Michael Wehner, a senior staff scientist at the Lawrence Berkeley National Laboratory, once succinctly put it to Mother Jones: “It’s not: Climate change flooded my house. It’s: Climate change changed the chances of flooding my house.” So, let’s look at the chances.
A recent study found that the prime wildfire conditions in Canada this year, which caused the choking smoke on the East Coast, were “at least twice as likely to occur there as they would be in a world that humans hadn’t warmed by burning fossil fuels,” The New York Times reports. The July heat dome that baked the South was “at least five times more likely due to human-caused climate change,” an analysis by Climate Central and The Guardian found. The odds of Vermont’s supposedly once-a-century flooding happening within 12 years of another 100-year storm in the state, Hurricane Irene, was just 0.6 percent. The fires in Maui were caused by compounding climate problems, The Washington Post reports, such as higher average temperatures and more intense hurricanes — both of which also have links to emissions-fueled warming. And Hurricane Idalia’s rapid intensification is what we’d expect to see from human-fueled ocean warming, too. Then there’s El Niño, which plays a part in all this chaos as well; it’s why scientists expect next year to be an even bumpier ride for earthly life than this summer has been.
That might not be very heartening to hear but consider this: If you’re a resident of anywhere other than San Francisco and a few odd places like Alaska’s Bristol Bay Borough (population: 838), then this summer was your dry run. You’ve learned more than you ever expected you’d need to know about indoor air purification; you spent 90 minutes prepping for wildfire season; you’ve checked in on elderly neighbors; you’ve even brushed up on your gin rummy skills so you can stay off your phone when the power goes out during the next (or same?!) hurricane. Look at you go. You’re adaptable. Heck, even iced pumpkin spice lattes are starting to grow on you now.
Log in
To continue reading, log in to your account.
Create a Free Account
To unlock more free articles, please create a free account.
Recovering from the Los Angeles wildfires will be expensive. Really expensive. Insurance analysts and banks have already produced a wide range of estimates of both what insurance companies will pay out and overall economic loss. AccuWeatherhas put out an eye-catching preliminary figure of $52 billion to $57 billion for economic losses, with the service’s chief meteorologist saying that the fires have the potential to “become the worst wildfire in modern California history based on the number of structures burned and economic loss.” On Thursday, J.P. Morgan doubled its previous estimate for insured losses to $20 billion, with an economic loss figure of $50 billion — about the gross domestic product of the country of Jordan.
The startlingly high loss figures from a fire that has only lasted a few days and is (relatively) limited in scope show just how distinctly devastating an urban fire can be. Enormous wildfires thatcover millions of acres like the 2023 Canadian wildfires can spew ash and particulate matter all over the globe and burn for months, darkening skies and clogging airways in other countries. And smaller — and far deadlier fires — than those still do not produce the same financial roll.
It’s in coastal Southern California where you find large population centers areas known by all to be at extreme risk of fire. And so a fire there can destroy a whole neighborhood in a few hours and put the state’s insurance system into jeopardy.
One reason why the projected economic impacts of the fires are so high is that the structures that have burned and the land those structures sit on are very valuable. Pacific Palisades, Malibu, and Santa Monica contain some of the most sought-after real estate on planet earth, with typical home prices over $2 million. Pacific Palisades itself has median home values of around $3 million, according to JPMorgan Chase.
The AccuWeather estimates put the economic damage for the Los Angeles fires at several times previous large, urban fires — the Maui wildfire in 2023 was estimated to cause around $14 billion of economic loss, for example — while the figure would be about a third or a quarter of a large hurricane, which tend to strike areas with millions of people in them across several states.
“The fires have not been contained thus far and continue to spread, implying that estimates of potential economic and insured losses are likely to increase,” the JPMorgan analysts wrote Thursday.
That level of losses would make the fires costlier in economic terms than the 2018 Butte County Camp Fire, whose insured losses of $10 billion made it California’s costliest at the time. That fire was far larger than the Los Angeles fires, spreading over 150,000 acres compared to just over 17,000 acres for the Palisades Fire and over 10,000 acres for the Eaton Fire. It also led to more than 80 deaths in the town of Paradise.
So far, around 2,000 homes have been destroyed,according to the Los Angeles Times,a fraction of the more than 19,000 structures affected by the Camp Fire. The difference in estimated losses comes from the fact that homes in Pacific Palisades weigh in at more than six times those in rural Butte, according to JPMorgan.
While insured losses get the lion’s share of attention when it comes to the cost impacts of a natural disaster, the potential damages go far beyond the balance sheet of insurers.
For one, it’s likely that many affected homeowners did not even carry insurance, either because their insurers failed to renew their existing policies or the homeowners simply chose to go without due to the high cost of what insurance they could find. “A larger than usual portion of the losses caused by the wildfires will be uninsured,” according to Morningstar DBRS, which estimated total insured losses at more than $8 billion. Many homeowners carry insurance from California’s backup FAIR Plan, which may itself come under financial pressure, potentially leading to assessments from the state’s policyholders to bolster its ability to pay claims.
AccuWeather arrived at its economic impact figure by looking not just at losses from property damage but also wages that go unearned due to economic activity slowing down or halting in affected areas, infrastructure that needs to be repaired, supply chain issues, and transportation snarls. Even when homes and businesses aren’t destroyed, people may be unable to work due to evacuations; businesses may close due to the dispersal of their customers or inability of their suppliers to make deliveries. Smoke inhalation can lead to short-, medium-, and long-term health impacts that take a dent out of overall economic activity.
The high level of insured losses, meanwhile, could mean that insurers’ will see less surplus and could have to pay more for reinsurance, Nancy Watkins, an actuary and wildfire expert at Milliman, told me in an email. This may mean that they would have to shed yet more policies “in order to avoid deterioration in their financial strength ratings,” just as California has been trying to lure insurers back with reforms to its dysfunctional insurance market.
The economic costs of the fire will likely be felt for years if not decades. While it would take an act of God far stronger than a fire to keep people from building homes on the slopes of the Santa Monica Mountains or off the Pacific Coast, the city that rebuilds may be smaller, more heavily fortified, and more expensive than the one that existed at the end of last year. And that’s just before the next big fire.
Suburban streets, exploding pipes, and those Santa Ana winds, for starters.
A fire needs three things to burn: heat, fuel, and oxygen. The first is important: At some point this week, for a reason we have yet to discover and may never will, a piece of flammable material in Los Angeles County got hot enough to ignite. The last is essential: The resulting fires, which have now burned nearly 29,000 acres, are fanned by exceptionally powerful and dry Santa Ana winds.
But in the critical days ahead, it is that central ingredient that will preoccupy fire managers, emergency responders, and the public, who are watching their homes — wood-framed containers full of memories, primary documents, material wealth, sentimental heirlooms — transformed into raw fuel. “Grass is one fuel model; timber is another fuel model; brushes are another — there are dozens of fuel models,” Bobbie Scopa, a veteran firefighter and author of the memoir Both Sides of the Fire Line, told me. “But when a fire goes from the wildland into the urban interface, you’re now burning houses.”
This jump from chaparral shrubland into neighborhoods has frustrated firefighters’ efforts to gain an upper hand over the L.A. County fires. In the remote wilderness, firefighters can cut fire lines with axes, pulaskis, and shovels to contain the blaze. (A fire’s “containment” describes how much firefighters have encircled; 25% containment means a quarter of the fire perimeter is prevented from moving forward by manmade or natural fire breaks.)
Once a fire moves into an urban community and starts spreading house to house, however, as has already happened in Santa Monica, Pasadena, and other suburbs of Los Angeles, those strategies go out the window. A fire break starves a fire by introducing a gap in its fuel; it can be a cleared strip of vegetation, a river, or even a freeway. But you can’t just hack a fire break through a neighborhood. “Now you’re having to use big fire engines and spray lots of water,” Scopa said, compared to the wildlands where “we do a lot of firefighting without water.”
Water has already proven to be a significant issue in Los Angeles, where many hydrants near Palisades, the biggest of the five fires, had already gone dry by 3:00 a.m. Wednesday. “We’re fighting a wildfire with urban water systems, and that is really challenging,” Los Angeles Department of Water and Power CEO Janisse Quiñones explained in a news conference later that same day.
LADWP said it had filled its 114 water storage tanks before the fires started, but the city’s water supply was never intended to stop a 17,000-acre fire. The hydrants are “meant to put out a two-house fire, a one-house fire, or something like that,” Faith Kearns, a water and wildfire researcher at Arizona State University, told me. Additionally, homeowners sometimes leave their sprinklers on in the hopes that it will help protect their house, or try to fight fires with their own hoses. At a certain point, the system — just like the city personnel — becomes overwhelmed by the sheer magnitude of the unfolding disaster.
Making matters worse is the wind, which restricted some of the aerial support firefighters typically employ. As gusts slowed on Thursday, retardant and water drops were able to resume, helping firefighters in their efforts. (The Eaton Fire, while still technically 0% contained because there are no established fire lines, has “significantly stopped” growing, The New York Times reports). Still, firefighters don’t typically “paint” neighborhoods; the drops, which don’t put out fires entirely so much as suppress them enough that firefighters can fight them at close range, are a liability. Kearns, however, told me that “the winds were so high, they weren’t able to do the water drops that they normally do and that are an enormous part of all fire operations,” and that “certainly compounded the problems of the fire hydrants running dry.”
Firefighters’ priority isn’t saving structures, though. “Firefighters save lives first before they have to deal with fire,” Alexander Maranghides, a fire protection engineer at the National Institute of Standards and Technology and the author of an ongoing case study of the 2018 Camp fire in Paradise, California, told me. That can be an enormous and time-consuming task in a dense area like suburban Los Angeles, and counterintuitively lead to more areas burning down. Speaking specifically from his conclusions about the Camp fire, which was similarly a wildland-urban interface, or WUI fire, Maranghides added, “It is very, very challenging because as things deteriorate — you’re talking about downed power lines, smoke obstructing visibility, and you end up with burn-overs,” when a fire moves so quickly that it overtakes people or fire crews. “And now you have to go and rescue those civilians who are caught in those burn-overs.” Sometimes, that requires firefighters to do triage — and let blocks burn to save lives.
Perhaps most ominously, the problems don’t end once the fire is out. When a house burns down, it is often the case that its water pipes burst. (This also adds to the water shortage woes during the event.) But when firefighters are simultaneously pumping water out of other parts of the system, air can be sucked down into those open water pipes. And not just any air. “We’re not talking about forest smoke, which is bad; we’re talking about WUI smoke, which is bad plus,” Maranghides said, again referring to his research in Paradise. “It’s not just wood burning; it’s wood, plastics, heavy metals, computers, cars, batteries, everything. You don’t want to be breathing it, and you don’t want it going into your water system.”
Water infrastructure can be damaged in other ways, as well. Because fires are burning “so much hotter now,” Kearns told me, contamination can occur due to melting PVC piping, which releases benzene, a carcinogen. Watersheds and reservoirs are also in danger of extended contamination, particularly once rains finally do come and wash soot, silt, debris, and potentially toxic flame retardant into nearby streams.
But that’s a problem for the future. In the meantime, Los Angeles — and lots of it — continues to burn.
“I don’t care how many resources you have; when the fires are burning like they do when we have Santa Anas, there’s so little you can do,” Scopa said. “All you can do is try to protect the people and get the people out, and try to keep your firefighters safe.”
Plus 3 more outstanding questions about this ongoing emergency.
As Los Angeles continued to battle multiple big blazes ripping through some of the most beloved (and expensive) areas of the city on Thursday, a question lingered in the background: What caused the fires in the first place?
Though fires are less common in California during this time of the year, they aren’t unheard of. In early December 2017, power lines sparked the Thomas Fire near Ventura, California, which burned through to mid-January. At the time it was the largest fire in the state since at least the 1930s. Now it’s the ninth-largest. Although that fire was in a more rural area, it ignited for some of the same reasons we’re seeing fires this week.
Read on for everything we know so far about how the fires started.
Five major fires started during the Santa Ana wind event this week:
Officials have not made any statements about the cause of any of the fires yet.
On Thursday morning, Edward Nordskog, a retired fire investigator from the Los Angeles Sheriff’s Department, told me it was unlikely they had even begun looking into the root of the biggest and most destructive of the fires in the Pacific Palisades. “They don't start an investigation until it's safe to go into the area where the fire started, and it just hasn't been safe until probably today,” he said.
It can take years to determine the cause of a fire. Investigators did not pinpoint the cause of the Thomas Fire until March 2019, more than two years after it started.
But Nordskog doesn’t think it will take very long this time. It’s easier to narrow down the possibilities for an urban fire because there are typically both witnesses and surveillance footage, he told me. He said the most common causes of wildfires in Los Angeles are power lines and those started by unhoused people. They can also be caused by sparks from vehicles or equipment.
At about 27,000 acres burned, these fires are unlikely to make the charts for the largest in California history. But because they are burning in urban, densely populated, and expensive areas, they could be some of the most devastating. With an estimated 2,000 structures damaged so far, the Eaton and Palisades fires are likely to make the list for most destructive wildfire events in the state.
And they will certainly be at the top for costliest. The Palisades Fire has already been declared a likely contender for the most expensive wildfire in U.S. history. It has destroyed more than 1,000 structures in some of the most expensive zip codes in the country. Between that and the Eaton Fire, Accuweather estimates the damages could reach $57 billion.
While we don’t know the root causes of the ignitions, several factors came together to create perfect fire conditions in Southern California this week.
First, there’s the Santa Ana winds, an annual phenomenon in Southern California, when very dry, high-pressure air gets trapped in the Great Basin and begins escaping westward through mountain passes to lower-pressure areas along the coast. Most of the time, the wind in Los Angeles blows eastward from the ocean, but during a Santa Ana event, it changes direction, picking up speed as it rushes toward the sea.
Jon Keeley, a research scientist with the US Geological Survey and an adjunct professor at the University of California, Los Angeles told me that Santa Ana winds typically blow at maybe 30 to 40 miles per hour, while the winds this week hit upwards of 60 to 70 miles per hour. “More severe than is normal, but not unique,” he said. “We had similar severe winds in 2017 with the Thomas Fire.”
Second, Southern California is currently in the midst of extreme drought. Winter is typically a rainier season, but Los Angeles has seen less than half an inch of rain since July. That means that all the shrubland vegetation in the area is bone-dry. Again, Keeley said, this was not usual, but not unique. Some years are drier than others.
These fires were also not a question of fuel management, Keeley told me. “The fuels are not really the issue in these big fires. It's the extreme winds,” he said. “You can do prescription burning in chaparral and have essentially no impact on Santa Ana wind-driven fires.” As far as he can tell, based on information from CalFire, the Eaton Fire started on an urban street.
While it’s likely that climate change played a role in amplifying the drought, it’s hard to say how big a factor it was. Patrick Brown, a climate scientist at the Breakthrough Institute and adjunct professor at Johns Hopkins University, published a long post on X outlining the factors contributing to the fires, including a chart of historic rainfall during the winter in Los Angeles that shows oscillations between very wet and very dry years over the past eight decades. But climate change is expected to make dry years drier in Los Angeles. “The LA area is about 3°C warmer than it would be in preindustrial conditions, which (all else being equal) works to dry fuels and makes fires more intense,” Brown wrote.