From the Experts: Wrigley Institute Faculty Explain January 2025 Wildfire Issues
The January 2025 Los Angeles wildfire event will likely go down in history as one of the most destructive natural disasters in our nation’s history. On January 7, fires in the Pacific Palisades area of the Santa Monica Mountains and Eaton Canyon area of Altadena ignited quickly and spread rapidly, fueled by an unusually dense accumulation of dry brush and an unprecedented Santa Ana wind event with gusts reaching 100 miles per hour.
As of January 17, the two wildfires are significantly contained but still blazing. Together, they’ve killed 24 residents and destroyed 10,694 structures. Along with several smaller fires that ignited around the same time, they have burned through more than 38,000 acres and displaced hundreds of thousands of residents. Almost 180,000 residents remain under evacuation orders or warnings. Many people have lost both their homes and their livelihoods, and experts are anticipating a long-term toll on Angelenos’ physical and mental health.
So, exactly why have the January 2025 L.A. wildfires been so destructive? And is there anything we can do to prevent similar events in the future? At the Wrigley Institute, we tapped into the expertise of our core and affiliated faculty to help answer these and related questions. Keep reading to see what their research reveals about L.A. wildfire history, prevention, and more. (Responses have been lightly edited for length and clarity.)
When it comes to wildfire and wildfire management, what is normal for L.A. County?
We live in an area that is naturally fire-prone. In our Mediterranean climate, there is usually no rain from summer through fall. Even though native plants are adapted to these conditions, they dry out during this time and provide fuel for fires if ignited. This creates a typical fire season that overlaps with the dry season.
Jill Sohm, Director, USC Dornsife Environmental Studies Program and Associate Professor (Teaching) of Environmental Studies
We have a chaparral ecosystem, which needs fire to regenerate itself. Many of our native plants have evolved to depend on periodic fires for germinating seeds and regenerating, making fire key to maintaining the health of our ecosystem.
Monalisa Chatterjee, Associate Professor (Teaching) of Environmental Studies
If we go back deeply enough into the historic record, we find evidence of Indigenous burning, for both environmental management and spiritual reasons. As a tool for wildfire prevention, however, controlled burning was shelved by successive Spanish, Mexican, and American regimes. [Pre-20th century], we also did not see dense development climbing into canyons and the high spots of arroyos. Although fires are a normal part of the ecosystem we live with, their scale is rising exponentially year over year.
William Deverell, Professor of History, Spatial Sciences and Environmental Studies
Additional Resources
Story: How the U.S. shifted to a “zero-tolerance” wildfire policy >>
Why are wildfires becoming more extreme?
Climate change makes normal weather conditions worse, more extreme. So California has been experiencing more droughts and higher summer temperatures than normal. Increased drought and temperatures cause plants to dry out more completely, which causes fires to burn hotter and be more destructive when we have high wind conditions.
Jill Sohm, Director, USC Dornsife Environmental Studies Program and Associate Professor (Teaching) of Environmental Studies
Historically, L.A. county could expect more wintertime precipitation than we are now seeing. Our low humidity, the absence of rainfall, and ferocious winds make a recipe for catastrophe.
William Deverell, Professor of History, Spatial Sciences and Environmental Studies
Part of the problem is that, for several decades, we have been trying to prevent fires from occurring naturally. As a result, we have accumulated a lot of fuel. Then, we added a lot of non-native plants that dry out and burn quickly in our environment.
Monalisa Chatterjee, Associate Professor (Teaching) of Environmental Studies
What are the longer-term effects of fires like these?
The ecosystems in southern California are adapted to wildfire and will be able to recover, although we can help them along with restoration and planting efforts. The most immediate concerns are the health impacts of the air pollution created by the fires. Burned material included not just vegetation, but also homes filled with materials that are unsafe to inhale. Another concern is the potential for mudslides in areas that burned. Eventually rains will come, and the vegetation that normally helps prevent erosion and mudslides will not be there to hold the soil together.
Jill Sohm, Director, USC Dornsife Environmental Studies Program and Associate Professor (Teaching) of Environmental Studies
Wildfire impacts on air quality are most strong when the fire is burning and we are breathing smoke. Once the wildfire is put out, the overall threat decreases significantly. However, there is a secondary impact to worry about in locations that are really inundated with smoke. The smoke can settle on surfaces and be reintroduced into the atmosphere when it’s disturbed, causing lots of health problems.
Sam Silva, Assistant Professor of Earth Sciences, Civil and Environmental Engineering and Population and Public Health Sciences
We are seeing a lot of incidences of degraded water quality in communities affected by the fire. Residents are being told not to drink tap water. That cleanup will take some time.
Monalisa Chatterjee, Associate Professor (Teaching) of Environmental Studies
Additional Resources
Lingering wildfire smoke and how to clean it up >>
What are some of the challenges we face when trying to live more sustainably with wildfire, and how can we solve them?
In Southern California, we only put significant resources into building our emergency response teams, which are critical for managing wildfire risks but not enough. Generally speaking, we don’t prepare for wildfires, we react to wildfires. Land use is not sufficiently regulated, and people have little knowledge of best practices [for building in wildfire zones]. Invasive species are widespread, which increases the risk of wildfire, and information about wildfire risks is buried in complicated technical reports. Wildfires are rarely considered in the decisions we make about where we live, what kind of built environment we create, or how we build community.
Successful adaptation [to wildfire] requires adjustment in the way we live with the environment. It requires economic mechanisms that encourage residents to change the way they’re altering the physical environment. We also need to establish communication and consensus-building patterns, so that government agencies and residents can make quick decisions during emergencies without losing trust with each other.
Monalisa Chatterjee, Associate Professor (Teaching) of Environmental Studies
How we think about risk depends a lot on when we might be exposed to it, as well as the probability of exposure. A fire that might happen sometime in the future is heavily discounted [as a risk] in our minds. We tend to prioritize nearer-term risks and challenges, and ones that will happen with certainty or near-certainty. Of course, when a fire is raging near where you live, the risk is indeed very close in time and more certain in terms of probability. But by then, it’s too late to do much about it.
Another thing my collaborators and I have observed in our research is that when a fire has occurred, people tend to believe they just suffered their once-in-a-century or one-in-500-years event, so there’s no need to worry about the future. People go back to their lives [without adjusting their behaviors] when the fire has been extinguished. But in a place like Southern California, the annual fire probability is so high that we can’t use the old estimates of frequency. What might have been a once-in-a-century event a decade ago might now be something that happens roughly every 5 years.
Once we get into recovery mode, we need to think about the risks we face in areas where people are planning to rebuild. Let’s make sure that anything we build there is resilient and supported by the necessary disaster-management infrastructure. If we can’t guarantee either of these conditions, we should think twice about what and where we rebuild.
Joe Árvai, Director, USC Wrigley Institute for Environment and Sustainability; Dana and David Dornsife Chair and Professor of Psychology, Biological Sciences and Environmental Studies
The more difficult, expensive or complicated a behavior, the less likely people are to adopt it. Governments at all levels can take steps to reduce or eliminate these barriers through default options that are good for wildfire resilience, messages that highlight the popularity of a behavior, or by appealing to a broad diversity of values.
Additionally, for many situations, a decision to protect the environment is often seen as a sacrifice: we are giving something up, but not getting anything tangible in return. This is all the more challenging if we perceive that few of our neighbors are making these “sacrifices.”
Governments and community organizations can do important work in how they frame environmental action by switching from the language of sacrifice, hardship, and zero-sum games, to that of innovation and community. They can emphasize a life where we derive pleasure, self-worth, and identify not from endless consumption, but from relationships of trust and reciprocity with others and with the natural world.
Victoria Campbell-Árvai, Associate Professor (Teaching) of Environmental Studies
Disasters like this one make home insurance more expensive and harder to obtain in California. What changes might help with this problem?
If we want a robust insurance sector that covers extreme climate events in California, we will need to implement changes at the federal and state levels. Public agencies have to work with insurance companies to develop coverage that considers the actual losses of property owners, as well as profit for the sustainability of insurance companies. We also have to consider climate change and how it alters future risks.
Everyone benefits from fewer losses. Therefore, reducing the risk for everyone has to be a priority. For example, a bunch of dried leaves under a deck can affect the neighborhood during a wildfire. An insurance discount could be created for communities that regularly clear out dead leaves, brush, and other wildfire fuel, so that more communities will want to take that step.
Monalisa Chatterjee, Associate Professor (Teaching) of Environmental Studies
Additional Resources
How Californians are impacted by insurance changes >>
Insurance: The critical gap in California’s wildfire preparedness >>
In terms of policy or governance, what else can we do to reduce the likelihood of disasters like this?
State and local government officials need to consider how to reduce the risk of losses from wildfires and how to co-exist with wildfire as a natural part of this ecosystem. They can do this by a variety of means: regulating land use, managing brush, reinforcing emergency-response capacity, designing economic mechanisms that encourage communities to maintain their properties and enhance their defensible areas, and improving communication about wildfire risks when there is no emergency.
Overall, adaptation has to be prioritized at each level of governance and decision-making. The actionable items may be implemented locally, but those actions must be facilitated at every level. For example, we need more transparency about individual properties’ fire histories and risks in the wildland-urban interface. That way, buyers can consider these risks, and the responsibilities or costs that come with them, before buying a property. But to make this happen, state-level agencies will have to require property sellers or developers to disclose these risks during the sales process.
Monalisa Chatterjee, Associate Professor (Teaching) of Environmental Studies
What can we do as individual members of our communities?
Social connection (knowing your neighbor, feeling that you can rely on your neighbor in a crisis) is one of the most important variables that improves a community’s ability to adapt to climate change. Social connection is deeply rooted in traditions of trust and reciprocation. These relationships of trust and reciprocity can grow out of community-building events or projects.
Projects that both foster community connections and build wildfire resilience include community brush-clearing days, workshops on fire-resistant home construction, and landscape maintenance activities. As community members, we can supercharge these efforts by tapping into existing community-based organizations or by creating neighborhood associations that can marshal resources and apply for grant funding.
Victoria Campbell-Árvai, Associate Professor (Teaching) of Environmental Studies
Simple changes can help with reducing risk: planting native species [in our yards], developing community groups that maintain brush in the neighborhood, bringing new residents into conversations about best practices, or connecting swimming pools for use with sprinkler systems, just to name a few. We must consider a new way of defining and creating interconnected and interdependent neighborhoods.
Monalisa Chatterjee, Associate Professor (Teaching) of Environmental Studies
Researchers Who Contributed to This Story
Director, USC Wrigley Institute for Environment and Sustainability; Dana and David Dornsife Chair and Professor of Psychology, Biological Sciences and Environmental Studies
Árvai’s research focuses on improving the critical thinking, judgment, and decision-making capabilities of people. His research focuses primarily on situations involving risk, uncertainty, and tradeoffs between social, economic, and environmental objectives. His research also focuses on situations where people’s instinctive approach to judgment and decision-making is biased by unchecked emotions and motivated reasoning.
Associate Professor (Teaching) of Environmental Studies
Campbell-Árvai studies how people use information to form judgements, make decisions, and adopt environmentally significant behaviors. She focuses especially on these actions in the context of energy and climate, urban ecosystems and ecosystem services (the ways ecosystems support human societies), and human-nature interactions.
Associate Professor (Teaching) of Environmental Studies
Chatterjee studies climate change risk, impacts, and vulnerability; constraints and barriers to climate adaptation; and how economic and environmental policies affect sustainable development. She focuses especially on urban environments, disadvantaged communities, translating scientific evidence for policymakers, and extreme climate risk management for vulnerable communities.
Professor of History, Spatial Sciences and Environmental Studies
Deverell is an American historian who studies the 19th- and 20th-century American West, including its environmental and wildfire history. He is also the founding director of the Huntington-USC Institute on California and the West.
Assistant Professor of Earth Sciences, Civil and Environmental Engineering and Population and Public Health Sciences
Silva studies atmospheric chemistry and composition, including air quality and climate change. He focuses especially on using modern data science and machine learning to help build computer models of the atmosphere and cloud patterns.
Director, USC Dornsife Environmental Studies Program; Associate Professor (Teaching) of Environmental Studies
Sohm’s research background is in biological oceanography and microbial ecology, but her teaching and research experience encompass a wide range of interdisciplinary environmental issues. She currently focuses on Southern California ecosystems, with recent projects studying water pollution’s relationship to socioeconomic data, how the decay of invasive seaweed affects marine environments, aquaponics food systems, and native plant restorations along shorelines.