Research Database
Displaying 1 - 20 of 91
Spatiotemporal Synchrony of Climate and Fire Occurrence Across North American Forests (1750–1880)
Year: 2025
Aim: Increasing aridity has driven widespread synchronous fire occurrence in recent decades across North America. The lack of historical (pre-1880) fire records limits our ability to understand long-term continental fire-climate dynamics. The goal of this study is to use tree-ring reconstructions to determine the relationships between spatiotemporal patterns in historical climate and widespread fire occurrence in North American forests, and whether they are stable through time. This information will address a major knowledge gap required to inform projections of future fire.Location: North…
Publication Type: Journal Article
Equity in resilience: a case study of community resilience to wildfire in southwestern Oregon, United States
Year: 2025
In the fire-prone and fire-adapted landscape of the Rogue River Basin of southwestern Oregon, communities mobilize to prepare, respond, and recover from wildfire while modifying the current social and ecological system. Marginalized communities are often most affected and least prepared for disturbances of this kind, where racism, colonialism, and structural equities prevent meaningful inclusion and equitable allocation of resources. This research centers these voices in an empirical study of the situated resilience of the Rogue River Basin, rooted in the work of community-based organizations…
Publication Type: Journal Article
Bridging scales for landscape-level wildfire adaptation: A case study of the Kittitas Fire Adapted Communities Coalition
Year: 2024
Federal-level strategies or guidance for addressing wildfire risk encourage adaptation activities that span progressively larger scales, often focusing on landscape-level action that necessitates coordination between decision-makers and socially diverse communities. Collaborative organizations are increasingly explored as one approach for coordinating local efforts that address wildfire risk and adaptation, offering a platform for scaling and adjusting federal and state guidance that align with the needs of local landscapes. We conducted semi-structured interviews with members and supporters…
Publication Type: Journal Article
Fire history in northern Sierra Nevada mixed conifer forests across a distinct gradient in productivity
Year: 2024
BackgroundUnderstanding the role of fire in forested landscapes is fundamental to fire reintroduction efforts, yet few studies have examined how fire dynamics vary in response to interactions between local conditions, such as soil productivity, and more broadscale changes in climate. In this study, we examined historical fire frequency, seasonality, and spatial patterning in mixed conifer forests across a distinct gradient of soil productivity in the northern Sierra Nevada. We cross-dated 46 different wood samples containing 377 fire scars from 6 paired sites, located on and off of…
Publication Type: Journal Article
Increasing prevalence of hot drought across western North America since the 16th century
Year: 2024
Across western North America (WNA), 20th-21st century anthropogenic warming has increased the prevalence and severity of concurrent drought and heat events, also termed hot droughts. However, the lack of independent spatial reconstructions of both soil moisture and temperature limits the potential to identify these events in the past and to place them in a long-term context. We develop the Western North American Temperature Atlas (WNATA), a data-independent 0.5° gridded reconstruction of summer maximum temperatures back to the 16th century. Our evaluation of the WNATA with existing…
Publication Type: Journal Article
Application of Participatory Process Mapping to Evaluate Environmental Decision-Making and Implementation
Year: 2024
Environmental governance outcomes hinge on the design and implementation of management decisions. Yet, available research methodologies can be limited in their ability to capture the complexity of decision-making and implementation processes and in turn predict and explain environmental governance outcomes. We present participatory process mapping as a method for examining the pathways that emerge and evolve over time that result in natural resource management decisions and on-the-ground outcomes, as perceived by participants in collaborative processes. The approach leverages a large-N…
Publication Type: Journal Article
Managing fire-prone forests in a time of decreasing carbon carrying capacity
Year: 2024
Changing climatic conditions are increasing overstory tree mortality in forests globally. This restructuring of the distribution of biomass is making already flammable forests more combustible, posing a major challenge for managing the transition to a lower biomass state. In western US dry conifer forests, tree density resulting from over a century of fire-exclusion practices has increased the risk of high-severity wildfire and susceptibility to climate-driven mortality. Reducing dead fuel loads will require new approaches to mitigate risk to the remaining live trees by preparing forests to…
Publication Type: Journal Article
Prefire Drought Intensity Drives Postfire Recovery and Mortality in Pinus monticola and Pseudotsuga menziesii Saplings
Year: 2024
Increasing frequency of droughts and wildfire are sparking concerns that these compounded disturbance events are pushing forested ecosystems beyond recovery. An improved understanding of how compounded events affect tree physiology and mortality is needed given the reliance of fire management planning on accurate estimates of postfire tree mortality. In this study, we use a toxicological dose-response approach to quantify the impact of variable-intensity drought and fire on the physiology and mortality of Pinus monticola and Pseudotsuga menziesii saplings. We show that the…
Publication Type: Journal Article
Drought before fire increases tree mortality after fire
Year: 2024
Fire and drought are expected to increase in frequency and severity in temperate forests due to climate change. To evaluate whether drought increases the likelihood of post-fire tree mortality, we used a large database of tree survival and mortality from 32 years of wildland fires covering four dominant western North American conifers. We used Bayesian hierarchical modeling to predict the probability of individual tree mortality after fire based on species—Pinus contorta (lodgepole pine), Abies concolor (white fir), Pseudotsuga menziesii (Douglas-fir), and Pinus…
Publication Type: Journal Article
Drought triggers and sustains overnight fires in North America
Year: 2024
Overnight fires are emerging in North America with previously unknown drivers and implications. This notable phenomenon challenges the traditional understanding of the ‘active day, quiet night’ model of the diurnal fire cycle1,2,3 and current fire management practices4,…
Publication Type: Journal Article
An optimization model to prioritize fuel treatments within a landscape fuel break network
Year: 2024
We present a mixed integer programming model for prioritizing fuel treatments within a landscape fuel break network to maximize protection against wildfires, measured by the total fire size reduction or the sum of Wildland Urban Interface areas avoided from burning. This model uses a large dataset of simulated wildfires in a large landscape to inform fuel break treatment decisions. Its mathematical formulation is concise and computationally efficient, allowing for customization and expansion to address more complex and challenging fuel break management problems in diverse landscapes. We…
Publication Type: Journal Article
Factors influencing wildfire management decisions after the 2009 US federal policy update
Year: 2024
Background
The decision making process undertaken during wildfire responses is complex and prone to uncertainty. In the US, decisions federal land managers make are influenced by numerous and often competing factors.
Aims
To assess and validate the presence of decision factors relevant to the wildfire decision making context that were previously known and to identify those that have emerged since the US federal wildfire policy was updated in 2009.
Methods
Interviews were conducted across the US while wildfires were actively burning to elucidate time-of-fire decision factors. Data…
Publication Type: Journal Article
Anthropogenic climate change has reduced drought recovery probabilities across the western US
Year: 2024
During drought, resource managers want to know when the drought will end to make informed management decisions. However, as anthropogenic climate change has intensified drought conditions, we hypothesize it has affected drought recovery. Here, we leverage monthly self-calibrating Palmer Drought Severity Index data across the western US derived from observations and climate models, and quantify the probability of drought recovery following severe drought. We find that the probability of drought recovery is ~25–50% lower in recent decades (2000–2021) than in the historical record (1901–1980),…
Publication Type: Journal Article
The impacts of rising vapour pressure deficit in natural and managed ecosystems
Year: 2024
An exponential rise in the atmospheric vapour pressure deficit (VPD) is among the most consequential impacts of climate change in terrestrial ecosystems. Rising VPD has negative and cascading effects on nearly all aspects of plant function including photosynthesis, water status, growth and survival. These responses are exacerbated by land–atmosphere interactions that couple VPD to soil water and govern the evolution of drought, affecting a range of ecosystem services including carbon uptake, biodiversity, the provisioning of water resources and crop yields. However, despite the…
Publication Type: Journal Article
Demand for Information for Wildland Fire Management
Year: 2024
Significant resources have been devoted to increasing the supply of data and information products for wildland fire management. There has been comparatively less emphasis on understanding the demand for these products. There are large differences in the number of information sources that fire managers use in decision making. We developed a value-of-information model for wildland fire managers to formulate hypotheses about what factors drive these differences. Data from a comprehensive internet survey targeting a well-defined population of the Southwest wildland fire managers are used to test…
Publication Type: Journal Article
Human and climatic influences on wildfires ignited by recreational activities in national forests in Washington, Oregon, and California
Year: 2023
In Washington, Oregon, and California, ignitions from recreational activities accounted for 12% of human-caused wildfires, and 8% of the area burned, from 1992–2020. Wildfires ignited by recreational activities not only increase fire suppression expenditures but have the potential to limit recreational activities traditionally associated with use of fire, such as camping. From 1992–2020, 50% of recreation-caused ignitions in these three states occurred on lands managed by the U.S. Forest Service. The mean annual number of recreation-caused ignitions on national forests in the three states…
Publication Type: Journal Article
A data‐driven analysis and optimization of the impact of prescribed fire programs on wildfire risk in different regions of the USA
Year: 2023
In the current century, wildfires have shown an increasing trend, causing a huge amount of direct and indirect losses in society. Different methods and efforts have been employed to reduce the frequency and intensity of the damages, one of which is implementing prescribed fires. Previous works have established that prescribed fires are effective at reducing the damage caused by wildfires. However, the actual impact of prescribed fire programs is dependent on factors such as where and when prescribed fires are conducted. In this paper, we propose a novel data-driven model studying the impact…
Publication Type: Journal Article
Recent Douglas-fir Mortality in the Klamath Mountains Ecoregion of Oregon: Evidence for a Decline Spiral
Year: 2023
Recent increases in Douglas-fir (Psuedotsuga menziesii var. menziesii) mortality in the Klamath Mountains ecoregion raise concerns about the long-term resilience of Douglas-fir in the ecoregion and increased potential for uncharacteristic wildfire. We used data from the USDA Forest Service Aerial Detection Survey and ninety-six field plots to explore the relationships between physiographic and climate variables and Douglas-fir mortality. Our results provide strong evidence for a decline spiral in which Douglas-fir growing on hot, dry sites (predisposing factor) are further stressed by drought…
Publication Type: Journal Article
Quantifying the contribution of major carbon producers to increases in vapor pressure deficit and burned area in western US and southwestern Canadian forests
Year: 2023
Increases in burned forest area across the western United States and southwestern Canada over the last several decades have been partially driven by a rise in vapor pressure deficit (VPD), a measure of the atmosphere’s drying power that is significantly influenced by human-caused climate change. Previous research has quantified the contribution of carbon emissions traced back to a set of 88 major fossil fuel producers and cement manufacturers to historical global mean temperature rise. In this study, we extend that research into the domain of forest fires. We use a global energy balance…
Publication Type: Journal Article
The Fire Adapted Communities Pathways Tool: Facilitating Social Learning and a Science of Practice
Year: 2023
Wildfire science, policy, and practice lack systematic means for “tailoring” fire adaptation practices to socially diverse human populations and in ways that aggregate existing lessons. This article outlines the development and initial operationalization of the Fire Adapted Communities Pathways Tool, an inductive set of processes that help facilitate dialogue about needs and priorities for wildfire adaptation strategies across ownership boundaries or partners. We outline the stages and considerations organized by the tool, including how its components build from decades of social science and…
Communicating about Fire, Public Perceptions of Fire and Smoke, Social and Community Impacts of Fire
Publication Type: Journal Article