- Changing fire regimes are profoundly impacting ecosystems and society, requiring rapid advancement in fire-related knowledge within and across disciplines. Given the influx of new disciplines into the fire field, a lack of transparent vocabulary for the application and interpretation of fire regime attributes and fire metrics impedes the capacity to scale ecological knowledge across ecosystems and continents.
- In this article, we acknowledge there are many ways to define or measure fire metrics, but demonstrate how precision and context are important for interpreting fire…
Research Database
Displaying 101 - 120 of 294
Fire in focus: Clarifying metrics and terminology for better ecological insight
Year: 2025
Publication Type: Journal Article
Wildfires will intensify in the wildland-urban interface under near-term warming
Year: 2025
Dangerous fire weather is increasing under climate change, but there is limited knowledge of how this will affect fire intensity, a critical determinant of the socioecological effects of wildfire. Here, we model relationships between satellite observations of fire radiative power (FRP) and contemporaneous fire weather index, and then we project how FRP is likely to change under near-term warming scenarios. The models project widespread growth in FRP, with increases expected across 88% of fire-prone areas worldwide under 1.5 °C warming. Projected increases in FRP were highest in the…
Publication Type: Journal Article
A novel methodology to assess fuel treatment effectiveness: application to California’s forests
Year: 2025
Background. Fuel treatments are increasingly used to mitigate wildfire risks. Aims. Proposing a novel, scalable and transferable methodology, this study investigates which treatment is (more) effective at a regional scale. Methods. This research evaluates the effectiveness of fuel treatments in California forests using the Fuel Treatment Effectiveness Monitoring (FTEM) database, which provides a binary (yes/no) assessment of treatment efficacy based on a structured subjective evaluation process. Proposed methodology enables scaling up site-specific treatment outcomes to the regional…
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
Mapping Community Capacity to Reduce Vulnerability to Wildfire in Colorado, USA
Year: 2025
Communities can face significant risk from wildfire, often compounded by climate change and legacies of industrial forest management. Policies and collaborative approaches for managing wildfire risk have evolved to include greater roles and responsibilities for these communities, yet local communities often lack the capacity to plan and implement actions to reduce risk of, respond to, and recover from wildfire. In this paper, we explore spatial patterns of local capacity relative to wildfire risk across the state of Colorado, USA, with the aim of informing efforts to reduce vulnerability.…
Publication Type: Journal Article
Contextualizing recent increases in Canadian boreal wildfire activity: decadal burn rates still within historical variability of the two past centuries
Year: 2025
With approximately 15 million hectares burned, the 2023 wildfire season in Canada was exceptional. However, it remains unclear whether such recent increases in burned areas exceed the range of variability observed over past centuries. The objective of this study was to leverage available dendrochronological reconstructions of decadal burn rates to contextualize their recent increase within their historical variability over the past two centuries. We compared decadal burn rate reconstructions based on dendrochronological data (1800s–2023) for five large eastern and western Canadian boreal…
Publication Type: Journal Article
Effect of Recent Prescribed Burning and Land Management on Wildfire Burn Severity and Smoke Emissions in the Western United States
Year: 2025
Wildfires in the western US increasingly threaten infrastructure, air quality, and public health. Prescribed (“Rx”) fire is often proposed to mitigate future wildfires, but treatments remain limited, and few studies quantify their effectiveness on recent major wildfires. We investigate the effects of Rx fire treatments on subsequent burn severity across western US ecoregions and particulate matter (PM2.5) emissions in California. Using high-resolution (30-m) satellite imagery, land management records, and fire emissions data, we employ a quasi-experimental design to compare Rx fire-treated…
Publication Type: Journal Article
Air Quality Impacts of the January 2025 Los Angeles Wildfires: Insights from Public Data Sources
Year: 2025
Smoke from the Los Angeles (LA) wildfires that started on January 7, 2025 caused severe air quality impacts across the region. Government agencies released guidance on assessing personal risk, pointing to publicly available data platforms that present information from monitoring networks and smoke plume outlines. Additional satellite-based products provide supporting information during dynamic wildfire smoke events. We evaluate the regional air quality impacts of the fires through publicly available fine particulate matter (PM2.5) and nitrogen dioxide (NO2) observations from regulatory…
Publication Type: Journal Article
The Marshall Fire: Scientific and policy needs for water system disaster response
Year: 2023
The 2021 Marshall Fire was the costliest fire in Colorado's history and destroyed more than 1,000 homes and businesses. The disaster displaced over 40,000 people and damaged six public drinking water systems. A case study was developed to better understand decisions, resources, expertise, and response limitations during and after the wildfire. The fire caused all water systems to lose power. Power loss was sometimes coupled with structure destruction, distribution depressurization, and the failure of backup power systems. These consequences jeopardized fire-fighting support and allowed for…
Publication Type: Journal Article
Different approaches make comparing studies of burn severity challenging: a review of methods used to link remotely sensed data with the Composite Burn Index
Year: 2023
The Composite Burn Index (CBI) is commonly linked to remotely sensed data to understand spatial and temporal patterns of burn severity. However, a comprehensive understanding of the tradeoffs between different methods used to model CBI with remotely sensed data is lacking. To help understand the current state of the science, provide a blueprint towards conducting broad- scale meta-analyses, and identify key decision points and potential rationale, we conducted a review of studies that linked remotely sensed data to continuous estimates of burn severity measured with the CBI and related…
Publication Type: Journal Article
Conifer encroachment increases foliar moisture content in a northwestern California oak woodland
Year: 2023
Foliar moisture content influences crown fire ignition and behaviour. Some spatial variation in foliar moisture is attributable to differences in stand conditions but evidence describing this role is lacking or contradicting. Aims. To examine the role of stand conditions on tree physiology and foliar moisture content in Oregon white oak (Quercus garryana) and Douglas-fir (Pseudotsuga menziesii). Methods. We monitored foliar moisture content in both species, and tree physiology (stomatal conductance and leaf water potential) in oak, across three stand conditions, including intact stands (…
Publication Type: Journal Article
Examining the influence of mid-tropospheric conditions and surface wind changes on extremely large fires and fire growth days
Year: 2023
Background: Previous work by the author and others has examined weather associated with growth of exceptionally large fires (‘Fires of Unusual Size’, or FOUS), looking at three of four factors associated with critical fire weather patterns: antecedent drying, high wind and low humidity. However, the authors did not examine atmospheric stability, the fourth factor. Aims: This study examined the relationships of mid-tropospheric stability and dryness used in the Haines Index, and changes in surface wind speed or direction, to growth of FOUS. Methods. Weather measures were paired with daily…
Publication Type: Journal Article
Environmental justice analysis of wildfire-related PM2.5 exposure using low-cost sensors in California
Year: 2023
Highlights • Wildfire may exacerbate health disparities & environmental justice concerns. • Low-cost PM2.5 sensors improve wildfire impact assessment. • Increases in PM2.5 correlate with wildfire activity (within 30 km). • Indoor increases in PM2.5 concentrations mimic outdoor PM2.5 increase patterns. The increasing number and severity of wildfires is negatively impacting air quality for millions of California residents each year. Community exposure to PM2.5 in two main population centers (San Francisco Bay area and Los Angeles County area) was assessed using the low-cost PurpleAir sensor…
Publication Type: Journal Article
High-severity burned area and proportion exceed historic conditions in Sierra Nevada, California, and adjacent ranges
Year: 2023
Although fire is a fundamental ecological process in western North American forests, climate warming and accumulating forest fuels due to fire suppression have led to wildfires that burn at high severity across larger fractions of their footprint than were historically typical. These trends have spiked upwards in recent years and are particularly pronounced in the Sierra Nevada–Southern Cascades ecoregion of California, USA, and neighboring states. We assessed annual area burned (AAB) and percentage of area burned at high and low-to-moderate severity for seven major forest types in this…
Publication Type: Journal Article
High-severity fire drives persistent floristic homogenization in human-altered forests
Year: 2023
Ecological disturbance regimes across the globe are being altered via direct and indirect human influences. Biodiversity loss at multiple scales can be a direct outcome of these shifts. Fire, especially in dry forests, is an ecological disturbance that is experiencing dramatic changes due to climate change, fire suppression, increased human population in fire-prone areas, and alterations to vegetation composition and structure. Dry western conifer forests that historically experienced frequent, low-severity fires are now increasingly burning at high severity. Relatively little work has been…
Publication Type: Journal Article
Fuel Profiles and Biomass Carbon Following Bark Beetle Outbreaks: Insights for Disturbance Interactions from a Historical Silvicultural Experiment
Year: 2023
Anticipating consequences of disturbance interactions on ecosystem structure and function is a critical management priority as disturbance activity increases with warming climate. Across the Northern Hemisphere, extensive tree mortality from recent bark beetle outbreaks raises concerns about potential fire behavior and post-fire forest function. Silvicultural treatments (that is, partial or complete cutting of forest stands) may reduce outbreak severity and subsequent fuel loads, but longevity of pre-outbreak treatment effects on outbreak severity and post-outbreak fuel profiles remains…
Publication Type: Journal Article
Forecasting natural regeneration of sagebrush after wildfires using population models and spatial matching
Year: 2023
Context Addressing ecosystem degradation in the Anthropocene will require ecological restoration across large spatial extents. Identifying areas where natural regeneration will occur without direct resource investment will improve scalability of restoration actions. Objectives An ecoregion in need of large scale restoration is the Great Basin of the Western US, where increasingly large and frequent wildfires threaten ecosystem integrity and its foundational shrub species. We develop a framework to forecast where post-wildfire regeneration of sagebrush cover (Artemisia spp.) is likely to occur…
Publication Type: Journal Article
Lizards' response to the sound of fire is modified by fire history
Year: 2023
Highlights • Lizards surviving wildfires are more alert to fire sound than those in unburned areas. • Lizards living in urban areas reacted to fire sound similarly to wildfire survivors. • Both natural and human-driven disturbances can shape the behaviour of animals. • Fires are likely to be an important selective pressure on animal behaviour. Many animals survive wildfires; however, the mechanisms used to detect and respond to fire have been poorly studied. Sensory cues like sight and sound are used to recognize threats (e.g. predators) and elicit escape responses in prey. Similarly, these…
Publication Type: Journal Article
Prescribed fire after thinning increased resistance of sub-Mediterranean pine forests to drought events and wildfires
Year: 2023
Vegetation structure affects the vulnerability of a forest to drought events and wildfires. Management decisions, such as thinning intensity and type of understory treatment, influence competition for water resources and amount of fuel available. While heavy thinning effectively reduces tree water stress and intensity of a crown fire, the duration of these benefits may be limited by a fast growth response of the understory. Our aim was to study the effect of forest structure on pine forests vulnerability to extreme drought events and on the potential wildfire behaviour after management, with…
Publication Type: Journal Article
The outsized role of California’s largest wildfires in changing forest burn patterns and coarsening ecosystem scale
Year: 2023
Highlights • We evaluated trends for 1,809 fires that burned 1985–2020 across California forests. • Top 1% of fires by size burned 47% of total area burned across the study period. • Top 1% (18 fires) produced 58% of high and 42% of low-moderate severity area. • Top 1% created novel landscape patterns of large burn severity patches. • These large fires create new opportunities for managing forest resilience. Although recent large wildfires in California forests are well publicized in media and scientific literature, their cumulative effects on forest structure and implications for forest…
Publication Type: Journal Article