Research Database
Displaying 21 - 40 of 127
Compounding effects of climate change and WUI expansion quadruple the likelihood of extreme-impact wildfires in California
Year: 2025
Previous research has examined individual factors contributing to wildfire risk, but the compounding effects of these factors remain underexplored. Here, we introduce the “Integrated Human-centric Wildfire Risk Index (IHWRI)” to quantify the compounding effects of fire-weather intensification and anthropogenic factors—including ignitions and human settlement into wildland—on wildfire risk. While climatic trends increased the frequency of high-risk fire-weather by 2.5-fold, the combination of this trend with wildland-urban interface expansion led to a 4.1-fold increase in the frequency of…
Publication Type: Journal Article
Aspen impedes wildfire spread in southwestern United States landscapes
Year: 2025
Aspen (Populus tremuloides) forests are generally thought to impede fire spread, yet the extent of this effect is not well quantified in relation to other vegetation types. We examined the influence of aspen cover on interpolated daily fire spread rates, the relative abundance of aspen at fire perimeters versus burn interiors, and whether these relationships shifted under more fire-conducive atmospheric conditions. Our study incorporated 314 fires occurring between 2001 and 2020 in the southwestern United States and a suite of gridded vegetation, topography, and fire weather…
Publication Type: Journal Article
Changing fire regimes in the Great Basin USA
Year: 2025
Wildfire is a natural disturbance in landscapes of the Western United States, but the effects and extents of fire are changing. Differences between historical and contemporary fire regimes can help identify reasons for observed changes in landscape composition. People living and working in the Great Basin, USA, are observing altered fire conditions, but spatial information about the degree and direction of change and departure from historical fire regimes is lacking. This study estimates how fire regimes have changed in the major Great Basin vegetation types over the past 60 years with…
Publication Type: Journal Article
Integrating fire-smart fuels management with bioenergy benefits remote and Indigenous communities in Canada
Year: 2025
The global urgency of more damaging wildfires calls for proactive solutions. Integrating fire-smart fuels management with bioenergy could reduce wildfire risk while providing feedstock for bioenergy. We explore this strategy in off-grid communities in Canada who are heavily dependent on diesel for their energy needs, many of which are home to Indigenous peoples. Combining national remote sensing data and community-based information, we identify 33 diesel-dependent communities at high wildfire risk due to a large accumulation of undisturbed flammable forest. We demonstrate that 30 of these 33…
Publication Type: Journal Article
Insights Into Nature-Based Climate Solutions: Managing Forests for Climate Resilience and Carbon Stability
Year: 2025
Successful implementation of forest management as a nature-based climate solution is dependent on the durability of management-induced changes in forest carbon storage and sequestration. As forests face unprecedented stability risks in the face of ongoing climate change, much remains unknown regarding how management will impact forest stability, or how interactions with climate might shift the response of forests to management across spatiotemporal scales. Here, we used a process-based model to simulate multidecadal projections of forest dynamics in response to changes in management and…
Publication Type: Journal Article
Increasing Hydroclimatic Whiplash Can Amplify Wildfire Risk in a Warming Climate
Year: 2025
On January 7 and 8, 2025, a series of wind-driven wildfires occurred in Los Angeles County in Southern California. Two of these fires ignited in dense woody chaparral shrubland and immediately burned into adjacent populated areas–the Palisades Fire on the coastal slopes of the Santa Monica Mountains and the Eaton fire in the foothills of the San Gabriel Mountains. Both fires ultimately eclipsed the traditionally-defined “wildland-urban interface” boundaries by burning structure-to-structure as an urban conflagration. The scope of the devastation is staggering; at the time of writing, the…
Publication Type: Report
Farming and ranching through wildfire: Producers’ critical role in fire risk management and emergency response
Year: 2025
Wildfires increasingly threaten California’s agricultural sector, posing serious risks to farming, ranching, and food systems. We conducted a survey of 505 California farmers and ranchers affected by wildfires between 2017 and 2023. Main findings show that wildfires’ impacts on producers are extensive and range from mild to catastrophic, with both short and long-term repercussions, regardless of their exposure level. Producers play a central role in community emergency wildfire risk response and management by reducing fuel loads, creating defensible space, and leveraging their fire management…
Publication Type: Journal Article
Patterns and trends of heat and wildfire smoke indicators across rural–urban and social vulnerability gradients in Idaho
Year: 2025
Climate change poses a grave threat to human health with disparate impacts across society. While populations with high social vulnerability generally bear a larger burden of exposure to and impact from environmental hazards; such patterns and trends are less explored at the confluence of social vulnerability and rural–urban gradients. We show that in rural regions in Idaho, low vulnerability populations had both the highest long-term average and the highest increase rate of exposure to heatwaves from 2002–2020, coincident with a higher population density in low—as compared to high—…
Publication Type: Journal Article
Trees in Fire-Maintained Forests Have Similar Growth Responses to Drought, but Greater Stomatal Conductance Than Trees in Fire-Excluded Forests
Year: 2025
In the western US, increased tree density in dry conifer forests from fire exclusion has caused tree growth declines, which is being compounded by hotter multi-year droughts. The reintroduction of frequent, low-severity wildfire reduces forest density by removing fire-intolerant trees, which can reduce competition for water and improve tree growth response to drought. We assessed how lower forest density following frequent, low-severity wildfire affected tree stomatal conductance and growth response to drought by coring and measuring competition surrounding ponderosa pines (Pinus…
Publication Type: Journal Article
Can ‘‘Fire Safe’’ Cigarettes (FSCs) Start Wildfires?
Year: 2025
Over the last 20 years, all states within the US have required all cigarettes sold to be ‘‘fire safe’’ or ‘‘fire standards compliant’’ meaning that they must pass ASTM standard E2187. Though these cigarettes are designed to self-extinguish, there have been recent studies suggesting that these ‘‘fire safe’’ cigarettes (FSCs) can still ignite mattresses and other furnishings, but there has been no guidance for fire investigators whether FSCs can ignite natural fuels, such as duff and needles, that can be the source of a wildland fire. This work sets out to investigate whether FSCs can indeed be…
Publication Type: Journal Article
How bureaucracies interact with Indigenous Fire Stewardship (IFS): a conceptual framework
Year: 2024
BackgroundIndigenous Fire Stewardship (IFS) is contested within settler-colonial contexts, where its development is shaped by complex and dynamic socio-cultural, legal, and political factors. This manuscript draws from the policy sciences to sketch out a “zone of interaction” between IFS and the state’s wildfire policy system. Drawing from the strategies of bureaucracies, our goal is to illustrate the patterns in this “zone of interaction,” and to identify the implications for IFS, as well as for Indigenous Peoples and landscapes.ResultsDrawing insights from the Australian and Canadian…
Publication Type: Journal Article
The influence of wildfire risk reduction programs and practices on recreation visitation
Year: 2024
Background: The increasing extent and severity of uncharacteristic wildfire has prompted numerous policies and programs promoting landscape-scale fuels reduction. Aims: We used novel data sources to measure how recreation was influenced by fuels reduction efforts under the US Forest Service Collaborative Forest Landscape Restoration (CFLR) Program. Methods: We used posts to four social media platforms to estimate the number of social media user-days within CFLR landscapes and asked: (1) did visitation within CFLR Program landscapes between…
Publication Type: Journal Article
Ladder fuels rather than canopy volumes consistently predict wildfire severity even in extreme topographic-weather conditions
Year: 2024
Drivers of forest wildfire severity include fuels, topography and weather. However, because only fuels can be actively managed, quantifying their effects on severity has become an urgent research priority. Here we employed GEDI spaceborne lidar to consistently assess how pre-fire forest fuel structure affected wildfire severity across 42 California wildfires between 2019–2021. Using a spatial-hierarchical modeling framework, we found a positive concave-down relationship between GEDI-derived fuel structure and wildfire severity, marked by increasing severity with greater fuel loads until a…
Publication Type: Journal Article
Coexisting with wildfire: strengthening collective capacity by changing the status quo
Year: 2024
This article is the fuller written version of the invited closing plenary given by the author at the 10th International Fire Ecology and Management Congress. The article provides a consideration of our capacity to cope, care, and coexist in a fiery world from a social and structural point of view. It focuses on privilege as the root cause of a long and troublesome history within the wildfire profession of not valuing all generational knowledge equally, not treating all cultures with the same respect, not embracing diversity and inclusion, and not affording the same status to all…
Publication Type: Conference Proceedings
Socially vulnerable US Pacific Northwest communities are more likely to experience wildfires
Year: 2024
Quantitative wildfire risk assessments increasingly are used to prioritize areas for investments in wildfire risk mitigation actions. However, current assessments of wildfire risk derived from fire models built primarily on biophysical data do not account for socioeconomic contexts that influence community vulnerability to wildfire. Research indicates that despite accounting for only a small proportion of high wildfire hazard areas, communities with fewer socioeconomic resources to devote to wildfire prevention and response may experience outsized exposure and impacts. We examined the…
Publication Type: Journal Article
The Efficacy of Red Flag Warnings in Mitigating Human-Caused Wildfires across the Western United States
Year: 2024
Red flag warnings (RFWs) are issued by the U.S. National Weather Service to alert fire and emergency response agencies of weather conditions that are conducive to extreme wildfire growth. Distinct from most weather warnings that aim to reduce exposure to anticipated hazards, RFWs may also mitigate hazards by reducing the occurrence of new ignitions. We examined the efficacy of RFWs as a means of limiting human-caused wildfire ignitions. From 2006 to 2020, approximately 8% of wildfires across the western United States and 19% of large wildfires (≥40 ha) occurred on days with RFWs. Although the…
Publication Type: Journal Article
Repeated fuel treatments fall short of fire-adapted regeneration objectives in a Sierra Nevada mixed conifer forest, USA
Year: 2024
Fire exclusion over the last two centuries has driven a significant fire deficit in the forests of western North America, leading to widespread changes in the composition and structure of these historically fire-adapted ecosystems. Fuel treatments have been increasingly applied over the last few decades to mitigate fire hazard, yet it is unclear whether these fuel-focused treatments restore the fire-adapted conditions and species that will allow forests to persist into the future. A vital prerequisite of restoring fire-adaptedness is ongoing establishment of fire-tolerant tree species, and…
Publication Type: Journal Article
Fire branding: Why do new residents make a burn scar their home?
Year: 2024
Researchers have sought to understand why wildland urban interface areas continue to expand in the United States despite increasing riskand loss to those areas. Using the case of the Camp Fire in northern California, which destroyed the town of Paradise and surrounding communities in the fall of 2018, this article explores how new arrivals to this area interact with rebuild institutions to evaluate their risk of future wildfires. The paper builds off of concepts of “disaster machine” (Pais and Elliott in Soc Forces 86(4):1415–1453, 2008) and “resilience gentrification” (Gould and Lewis, 2021…
Publication Type: Journal Article
Informing proactive wildfire management that benefits vulnerable communities and ecological values
Year: 2024
- In response to mounting wildfire risks, land managers across the country will need to dramatically increase proactive wildfire management (e.g. fuel and forest health treatments). While human communities vary widely in their vulnerability to the impacts of fire, these discrepancies have rarely informed prioritizations for wildfire mitigation treatments. The ecological values and ecosystem services provided by forests have also typically been secondary considerations.
- To identify locations across the conterminous US where proactive wildfire management is likely to be effective…
Publication Type: Journal Article
Exploring How Community Context Informs Variations in Local Perceptions of Forest Disturbance and Land Management in Colorado Over Time
Year: 2024
Placed-based socio-economic and biophysical context has been viewed as an essential driver in shaping perceptions of forest risks and land management. Growing evidence of the importance of diverse community context in forested landscapes sets the stage to further consider how people’s understandings of their local environment influence natural resource management preferences. However, research to date largely lacks considerations of how community context informs social responses to long-term environmental change over time. Using the mountain pine beetle (MPB) outbreak in Colorado, we analyze…
Publication Type: Journal Article