Research Database
Displaying 1 - 20 of 1663
Exposure and carbon risk for mature and old-growth forests from severe wildfire in the Pacific Northwest, U.S.A.
Year: 2026
Mature and old-growth forests (MOG) provide essential ecosystem services, yet they face increasing threats. Currently, high-intensity, high-severity wildfires are the main driver for loss of MOG on federally managed forests across the United States. Quantifying MOG forests with greatest exposure to stand-replacing wildfires provides essential information for land managers. We integrated geospatial data from fire behavior simulations (fire intensity), fire refugia prediction (fire severity), forest type mapping, and carbon estimates to assess exposure of MOG forests to stand-replacing…
Publication Type: Journal Article
A collaborative, cloud-based decision support system for structured wildfire risk mitigation planning
Year: 2026
Multi-stakeholder planning and prioritization for ecosystem management and wildfire risk mitigation are complicated by the need to balance a multitude of values, goals, viewpoints, and interests across large landscapes. Doing so requires quantifying current conditions, defining management feasibility constraints, modeling complex system responses under different management and disturbance scenarios, quantifying outcomes in terms of social values, weighing and assessing tradeoffs, and identifying optimal strategies. Beginning in the 2010s, structured wildfire risk assessment tools were…
Publication Type: Journal Article
Gazing into the flames: A guide to assessing the impacts of climate change on landscape fire
Year: 2026
Widespread impacts of landscape fire on ecosystems, societies, and the climate system itself have heightened the need to understand the potential future trajectory of fire under continued climate change. However, the complexity of fire makes climate change impact assessment challenging. The climate system influences fire in many ways, including through vegetation, fuel dryness, fire weather, and ignition. Furthermore, fire’s impacts are highly diverse, spanning threats to human and ecological values and beneficial ecosystem and cultural services. Here, we discuss the art and science of…
Publication Type: Journal Article
A historical analysis of factors driving the daily prioritization of wildland fires in California
Year: 2026
During periods of heightened wildland fire activity in the United States, multiagency coordinating groups must prioritize among multiple on-going fires to allocate scarce suppression resources. While many studies have explored factors that influence wildfire suppression expenditures and personnel allocation, understanding the specific factors that affect daily wildfire prioritization has remained unexplored. In this study, we first examine wildfire reporting and ranking processes across different regions of the United States to provide insight into criteria used for fire ranking. We then…
Publication Type: Journal Article
Indoor and Outdoor Volatile Organic Compound Levels during and after the 2025 Los Angeles Wildfires
Year: 2026
The January 2025 Los Angeles wildfires released large amounts of air pollutants and exposed millions of residents to smoke containing hazardous volatile organic compounds (VOCs). To assess exposure risks, we conducted indoor and outdoor VOCs sampling at 22 households near the Palisades and Eaton Fires across three phases: active burning with less than 50% containment (January 8–15), active burning period with more than 50% containment (January 24–31), and postfire (February 11–18). Outdoor benzene concentrations peaked during Phase 1, with a median (interquartile range) of 0.38 (0.27) ppb,…
Publication Type: Journal Article
Diverse historical fire disturbance and successional dynamics in Douglas-fir forests of the western Oregon Cascades, USA
Year: 2026
We created the first annually resolved records of historical fire occurrence coupled with precise estimates of tree establishment for the northern half of the west slope of the Oregon Cascades, a region that is home to some of the most productive forests on earth. Our reconstructions at 36 randomly located sites document exceptional diversity in historical fire disturbance and successional dynamics. Most stands where we collected data appear to have initiated following stand-replacing fire between 200 and 750 years ago, although many sites exhibited evidence of moderate-severity fire that…
Publication Type: Journal Article
Assessing the effectiveness of prescribed burning in limiting the spread of future wildfires
Year: 2026
Background. Prescribed burning is a widely-used fire management strategy for maintaining socioeconomic and ecological resilience by mitigating the impacts of wildfires. Monitoring the effectiveness of prescribed burns on future fire spread, however, is challenged by limited data availability and quality. Aims. We seek to create a simple, replicable approach to assess the likelihood of an unplanned fire being limited or contained by a previous fire using only feature boundaries. Methods. We first present methods to calculate the percentage of the back half of a feature boundary that…
Publication Type: Journal Article
Three-decade record of contiguous-U.S. national forest wildfires indicates increased density of ignitions near roads
Year: 2026
BackgroundRoads play an important role in managing fire on the national forests. But roads also are known to increase ignitions and damage ecosystems. Roads may limit the size of wildfires, which may be viewed as desirable where fires endanger human life and property or undesirable if roadlessness allows more land to experience the ecological benefits of fire. In this paper, we examine a large, nationwide dataset to determine whether roads on the national forests are associated with higher ignition density, and we examine patterns of fire size to see whether wilderness and…
Publication Type: Journal Article
Understanding rural adaptation to smoke from wildfires and forest management: insights for aligning approaches with community contexts
Year: 2026
BackgroundRural communities are increasingly impacted by smoke produced by wildfires and forest management activties. Understanding local influences on smoke adaptation and mitigation is critical to social adaptation as fire risk continues to rise.AimsWe sought to determine the role of local social context in smoke adaptation and gauge interest in adaptation strategies that might reduce exposure.MethodsWe conducted 46 semi-structured interviews with 56 residents and professionals in Parks, Arizona, USA, a rural community adjacent to public…
Publication Type: Journal Article
Environmental health hazards and wildland firefighting: a qualitative analysis
Year: 2026
BackgroundDespite growing attention to wildland firefighter safety, little is known about the full scope of environmental health hazards experienced occupationally. Previous research has documented exposures to carcinogens and combustion byproducts from smoke, dust, ash, engine exhaust, ignition devices, and location-specific chemical and radiological hazards. With growing attention to firefighters’ health outcomes, more research is needed on the environmental health hazards that they experience routinely and non-routinely. Qualitative research is well suited for exploratory…
Publication Type: Journal Article
The Western United States Large Forest-Fire Stochastic Simulator (WULFFSS) 1.0: a monthly gridded forest-fire model using interpretable statistics
Year: 2026
We developed the WULFFSS, a stochastic monthly gridded forest-fire model for the western United States (US). Operating at 12 km resolution, WULFFSS calculates monthly probabilities of fires that burn at least 100 ha of forest area as well as the forest area burned per fire. The model is forced by variables related to vegetation, topographic, anthropogenic, and climate factors, organized into three indices representing spatial, annual-cycle, and lower frequency temporal domains. These indices can interact, so variables promoting fire in one domain amplify fire-promoting effects in another.…
Publication Type: Journal Article
Beyond average: a new approach to calculating fire regime departures applied to Western United States forests
Year: 2026
BackgroundChanges in climate and vegetation, in combination with fire exclusion, are altering and homogenizing fire regime attributes compared to historical conditions. Fire regime changes are commonly quantified using departure metrics based on differences in measures of central tendency (i.e., means) between time periods. These metrics can mischaracterize complex changes to fire regime attributes because the distributions underlying these attributes are often not well described by parameters.ResultsWe developed a non-parametric index of fire regime…
Publication Type: Journal Article
Prenatal Exposure to Wildfire and Autism in Children
Year: 2026
Chronic health effects of wildfire PM2.5 on neurodevelopmental outcomes are largely unknown. Therefore, the effects of wildfire PM2.5 on autism were assessed in a southern California-based pregnancy cohort using Cox proportional hazard models. Exposure was estimated from 2006 to 2014 at maternal addresses across pregnancy and individual trimesters using three metrics: (1) mean wildfire PM2.5 concentration, (2) number of days of smoke exposure, and (3) number of waves of smoke exposure. Analysis was restricted to days over specific PM2.5 concentration thresholds (3 and 5 μg/m3). Nonmovers…
Publication Type: Journal Article
Fighting Fire With Fires: The Fire-Fuel Feedback Effect in Canadian Forests
Year: 2026
AimClimate-driven fire increases could be modified by fire-fuel feedback, as recent fires reduce burnable fuels for future fires. Knowing the effects of fire-fuel feedback is essential for more accurate projection of fire activity, which, however, has often been overlooked due to the challenge in its quantification. This study aims to project future fire activity under the changing climates with consideration for fire-fuel feedback effects across Canada.LocationCanadian forests.Time Period1981–2100.Major Taxa StudiedTrees.MethodsWe projected future changes in a full set of fire activity…
Publication Type: Journal Article
Health Impact Analysis of Wildfire Smoke-PM2.5 in Canada (2019–2023)
Year: 2026
Wildfires are a source of air pollution, including PM2.5. Exposure to PM2.5 from wildfire smoke is associated with adverse health effects including premature death and respiratory morbidity. Air quality modeling was performed to quantify seasonal wildfire-PM2.5 exposure across Canada for 2019–2023, and the annual acute and chronic health impacts and economic valuation due to wildfire-PM2.5 exposure were estimated. Exposure to wildfire-PM2.5 varied geospatially and temporally. For 2019–2023, the annual premature deaths attributable to wildfire-PM2.5 ranged from 49 (95% CI: 0–73) to 400 (95% CI…
Publication Type: Journal Article
An Assessment of Aerial Firefighting Response Times Between Agencies During the 2020 Fire Season in California
Year: 2026
Rapid, well‑coordinated aerial response can be an effective way to limit wildfire growth during the initial‑response period. To date, most studies of wildland fire aviation effectiveness have relied on data from aircraft provided by the United States Forest Service, while other agencies aircraft have received less attention. This study leverages open ADS‑B data to reconstruct second‑by‑second aircraft movements for both the CAL FIRE and USFS aircraft during the 2020 California fire season, allowing a comparison between use of different agency aircraft for the first time. This study…
Publication Type: Journal Article
Understanding unmet needs during community wildfire recovery: A case study of smoke damage impacts after the 2021 Marshall Fire
Year: 2026
Efforts to understand, assess, and address diversifying recovery needs have growing relevance as wildfires continue to impact communities. However, little is known about social experiences navigating gaps in assistance funding and support or “unmet needs” in post-fire spaces, particularly for indirect impacts like smoke damage. Determining how affected residents access available information and make decisions related to unmet needs can aid the development of resources and programs that support rapid identification of, and response to, emergent or undocumented impacts during recovery processes…
Publication Type: Journal Article
Wildfire research and mental health: impacts, reflections, and a call to action
Year: 2026
BackgroundIn response to record-breaking wildfire seasons worldwide, wildfire researchers are increasingly called upon to conduct research to better understand the drivers and impacts of “megafires.” However, there is limited attention to the mental health risks and potentially traumatizing experiences of working in these disaster-affected social-ecological landscapes, or the implications of this on our ability to conduct collaborative and trauma-informed research. In this forum, we seek to raise awareness and catalyze action within the wildfire community to sustain the…
Publication Type: Journal Article
Impact of Wildland Fire Smoke PM2.5 on Birth Weight in California
Year: 2026
The increase in the frequency, duration, and intensity of wildland fires is a significant source of air pollution that can impact perinatal outcomes. This study assessed associations between wildfire fine particulate matter <2.5 μm (PM2.5) and adverse birth weight outcomes among singleton term births in California for 2007–2018. Exposure was assessed using bias-corrected Community Multiscale Air Quality Model, linked to residence at delivery. Logistic and linear regression models estimated associations between average daily wildfire PM2.5 and birth weight outcomes, adjusting for individual…
Publication Type: Journal Article
Predictive Understanding of Wildfire Ignitions Across the Western United States
Year: 2026
Wildfires have increasingly affected human and natural systems across the western United States (WUS) in recent decades. Given that the majority of ignitions are human-caused and potentially preventable, improving the ability to predict fire occurrence is critical for effective wildfire prevention and risk mitigation. We used over 500,000 wildfire ignition records from 2000 to 2020 to develop machine learning models that predict daily ignition probability across the WUS and incorporate a wide range of physical, biological, social, and administrative variables. A key innovation of this work is…
Publication Type: Journal Article