California is once again in the middle of a devastating wildfire season. The two largest fires — the Dixie Fire and the Caldor Fire — have destroyed more than 2,000 buildings combined, many of them homes.
Fires are not just burning larger, but more destructively. Fire suppression techniques that have been employed for decades are no longer working against modern megafires, and some experts say that will require a shift in how we think about and respond to fires in California.
Crystal Kolden is a professor of fire science at UC Merced and what's known as a pyrogeographer, studying not just how fires function as a natural process, but how we humans interact with it as well. She is also trained as a wildland firefighter.
"I often say, let's be honest, I was not a very good firefighter," Kolden said. "I am not athletically inclined at all. And that is incredibly difficult work. But what I really got interested in was trying to understand what I was seeing on the landscape and why we were fighting fires in some of the most remote places in the U.S. that I knew had adapted to fire, that had evolved with fire."
Kolden spoke with Insight host Vicki Gonzalez about some of the reasons wildfires are getting larger, lasting longer and becoming more destructive, as well as explaining some solutions that are being discussed and applied.
This interview has been edited for length and clarity.
Interview Highlights
On how the job of a wildland firefighter has changed over time
It's a job that used to be pretty well confined to only the peak wildfire season, mostly in midsummer, sometimes until later fall in places like Southern California. And it was also a job that was mostly in relatively rural and wilderness-like areas, particularly for Forest Service firefighters. They rarely actually had to worry about houses 20, 30 years ago. But now what we see is increasingly our wildfires are occurring more and more in sort of these semi-rural and even close to suburban areas. And the job is really started to focus a lot more on how do we save lives and save homes. And that has been, I think, a real shift for a lot of our wildland firefighters. And it's something that has taken an enormous emotional and psychological toll on them.
Firefighters protect homes in Christmas Valley from the Caldor Fire Monday, Aug. 30, 2021.Andrew Nixon / CapRadio
On what stands out to her about the fires this year
Yeah, what's been really noticeable about the fires this year, particularly the Dixie Fire and the Caldor Fire, is that they both burned up and over the top of the Sierra Nevada crest. There had never been a modern fire that burned over an entire mountain range until last summer when the East Troublesome Fire burned over the Rockies in Colorado. And this year we had not just the first, but also the second large wildfire to burn up and over the Sierra Nevada crest. Which, when the Caldor fire started, I myself didn't think it would actually make it up and over the top. And so it's been really sort of very interesting as a scientist to try and look at, OK, what are the factors that we're seeing that are helping this fire burn so rapidly and evade containment? And both of these fires have really been a challenge for firefighters in the old tactics that used to work really successfully, just aren't working anymore.
On what changed for both of these to happen for the first time in California history
Yeah, so there's a lot of contributing factors to this, but chief is climate change. For anyone that's sort of paying attention to California, we're well aware of the impacts of climate change on our state because it has really produced numerous intense heat waves this summer. Of course, we're smack in the middle of a very severe drought that is actually impacting Northern California much more severely than Southern California.
And what climate change has done and facilitated, both last year's large fires and this year's large fires, is that it is drying out our fuels, our vegetation much earlier in the year. And part of what we're looking at with these two fires that summited the Sierra is that we lost our snowpack in the Sierra very early this year. By the first part of May, there was very little snowpack anywhere and even in some of the highest parts of the Sierra Nevada. And that's incredibly unusual because normally we've got snowpack well into July and a lot of parts of the Sierra. So those warmer conditions and spring really helped that snowpack melt early. And then that was followed by several heat waves in June and July that just dried out the ground, dried out all of the fuel, both the dead sticks and downed trees, and then the live standing vegetation as well, those trees and shrubs that fuel those fires.
On how warmer temperatures at night affect wildfires
One of the things that we watch really closely with wildfires is how warm it is at night, because nighttime is when that vegetation recovers some of its moisture. And so historically, we had seen that at nighttime fire behavior tended to die down. The dew point came up, we had the humidity come up and basically, that reduced the fire behavior. And oftentimes crews were able to move in and directly attack a fire safely and really move forward in containment. And what we've seen in the last few years and absolutely this year is that these fires are burning incredibly efficiently and actively at night. There's no break. There is no moment when the firefighters say, OK, it's dying down a little bit. I think we can get in there. And instead, they are the fires are chewing up large areas at night that they historically would not have done very, very much at all. So that has really driven the increase in size and the difficulty in containing these fires.
On why she thinks we’re responding to wildfires incorrectly
I believe we are, and the reason is very much historical. For over a hundred years, the U.S. Forest Service, when it was a fledgling agency in 1910, basically said, OK, Congress, give us our budget and our number one job is going to be to put out wildfires. And that legacy has basically brought us to this moment today where we still feel like we can control wildfire, right? And it's a function of wanting to control ignitions. And you know what I think a lot of people don't necessarily understand is that we've actually gotten very good at reducing ignitions. But most of those wildfires we still put out very successfully when they're tiny. It's that very, very small percent that take off and grow large and are difficult to contain.
And what we have done is try to keep containing them instead of saying, OK, we need to look at this as a disaster response instead of just stopping wildfires, because we approach things very differently. When you look at just what just happened last week with Hurricane Ida moving through the south, the response was very different. The goal was to understand where the hurricane was going to go, evacuate people out of the highest risk areas very, very quickly, and then move into the aftermath of the hurricane to recovery. And there was no discussion about sort of stopping the hurricane overall.
Linda and Jeff Sprague of Mendocino watch the Salt Fire spread in Shasta County.Andrew Nixon / CapRadio
On the need for more controlled burns
The lack of controlled burning, coupled with our century-long, very effective fire suppression campaign. is the other major factor driving these incredibly large fires that are so destructive. Because what has happened is that we've dramatically increased the amount of fuel in these forests. Essentially, instead of having the conditions for campfires, now we've got conditions for bonfires every single time a new fire starts because there's just so much more fuel and it's so much drier and ready to burn. And so we're behind and we need to do more controlled burning.
And it's sort of overcoming that lack of inertia in this area where we really need to stop and not worry so much about the fact that we're behind and just start burning and trying to change the culture, because there are a lot of discussions about why we can't do more burning, right? There's smoke issues, so it's too dangerous. We can't do these sorts of things. But every time that we put barriers up and say we can't get this done, we're kicking the can down the road and it's going to only just simply fuel another large destructive wildfire like the ones we've seen last summer, this summer.
On how the state could support cultural burning practices of Native American tribes
That's been a key challenge is actually trying to figure out how to support and empower the Indigenous people in our state who have continued burning despite all of the challenges that they have faced over the last century and a half. And there are several tribes in the state that have very strong burning cultures and want to actually burn more. And they've run into a lot of barriers in terms of state policy and some of the challenges of differential land ownership rights, their homelands, they understand how to burn it. But today it is technically under the ownership of the Forest Service or other types of private or state ownerships.
Something that was really encouraging is that last week the [California Assembly] passed two bills that are going to help solve this problem, and they were already passed in the Senate. So now they are going to Gov. Newsom's desk for signature. And we're all fingers crossed that he signs them very quickly.
On whether people should be allowed to live in fire-prone areas
That is the type of question that, again, showcases how we look at fire very differently from other natural hazards. This is a state of 40 million people and at least half of those 40 million people live on or near a large earthquake fault in San Francisco, in the whole Los Angeles, Southern California area. And those fault lines, when they rupture in the past, have been incredibly destructive, right? So why do we still allow people to live there and, in fact, build skyscrapers in these areas? Well, we figured out how to engineer mitigation measures, right? We understand how earthquakes function, and so we're able to mitigate that.
And we need to do the same for wildfire, because for so many people in a state that has one of the highest costs of living in the country, where we already have a housing shortage that has produced a crisis in this state, suggesting that the people who have moved to a lot of these rural areas because they can't afford to live anywhere else, that they shouldn't be able to live there anymore, where are they going to go? And again, we have a large Indigenous population in the state that has already been removed from so much of their homelands, and they are the people also who live in these rural fire-prone areas.
