Research Database
Displaying 121 - 140 of 240
The hot-dry-windy index: A new tool for forecasting fire weather
Year: 2020
Accurate predictions of how weather may affect a wildfire’s behavior are needed to protect crews on the line and efficiently allocate firefighting resources. Since 1988, fire meteorologists have used a tool called the Haines Index to predict days when the weather will exacerbate a wildfire. Although the Haines Index is widely believed to have value, it never received rigorous testing on the line. Even Don Haines, the U.S. Forest Service meteorologist who developed the index, has said the Haines Index needs further refinement. Recognizing that a new fire weather prediction tool was needed, a…
Publication Type: Report
Potential COVID-19 Outbreak in Fire Camp: Modeling Scenarios and Interventions
Year: 2020
The global COVID-19 pandemic will pose unique challenges to the management of wildlandfire in 2020. Fire camps may provide an ideal setting for the transmission of SARS-CoV-2, the virusthat causes COVID-19. However, intervention strategies can help minimize disease spread andreduce the risk to the firefighting community. We developed a COVID-19 epidemic model tohighlight the risks posed by the disease during wildland fire incidents. Our model accounts forthe transient nature of the population on a wildland fire incident, which poses unique risks to themanagement of communicable diseases in…
Publication Type: Journal Article
Prescribed fire science: the case for a refined research agenda
Year: 2020
The realm of wildland fire science encompasses both wild and prescribed fires. Most of the research in the broader field has focused on wildfires, however, despite the prevalence of prescribed fires and demonstrated need for science to guide its application. We argue that prescribed fire science requires a fundamentally different approach to connecting related disciplines of physical, natural, and social sciences. We also posit that research aimed at questions relevant to prescribed fire will improve overall wildland fire science and stimulate the development of useful knowledge about managed…
Publication Type: Journal Article
The Role of Previous Fires in the Management and Expenditures of Subsequent Large Wildfires
Year: 2019
Previously burned areas can influence the occurrence, extent, and severity of subsequent wildfires, which may influence expenditures on large fires. We develop a conceptual model of how interactions of fires with previously burned areas may influence fire management, fire behavior, expenditures, and test hypotheses using regression models of wildfire size and suppression expenditures. Using a sample of 722 large fires from the western United States, we observe whether a fire interacted with a previous fire, the percent area of fires burned by previous fires, and the percent perimeter overlap…
Publication Type: Journal Article
Evaluating Model Predictions of Fire Induced Tree Mortality Using Wildfire-Affected Forest Inventory Measurements
Year: 2019
Forest land managers rely on predictions of tree mortality generated from fire behavior models to identify stands for post-fire salvage and to design fuel reduction treatments that reduce mortality. A key challenge in improving the accuracy of these predictions is selecting appropriate wind and fuel moisture inputs. Our objective was to evaluate postfire mortality predictions using the Forest Vegetation Simulator Fire and Fuels Extension (FVS-FFE) to determine if using representative fire-weather data would improve prediction accuracy over two default weather scenarios. We used pre- and post-…
Publication Type: Journal Article
A Classification of US Wildland Firefighter Entrapments Based on Coincident Fuels, Weather, and Topography
Year: 2019
Previous attempts to identify the environmental factors associated with firefighter entrapments in the United States have suggested that there are several common denominators. Despite the widespread acceptance of the assumed commonalities, few studies have quantified how often entrapments actually meet these criteria. An analysis of the environmental conditions at the times and locations of 166 firefighter entrapments involving 1202 people and 117 fatalities that occurred between 1981 and 2017 in the conterminous United States revealed some surprising results. Contrary to general assumptions…
Publication Type: Journal Article
Factors Associated with Structure Loss in the 2013–2018 California Wildfires
Year: 2019
Tens of thousands of structures and hundreds of human lives have been lost in recent fire events throughout California. Given the potential for these types of wildfires to continue, the need to understand why and how structures are being destroyed has taken on a new level of urgency. We compiled and analyzed an extensive dataset of building inspectors’ reports documenting homeowner mitigation practices for more than 40,000 wildfire-exposed structures from 2013–2018. Comparing homes that survived fires to homes that were destroyed, we investigated the role of defensible space distance,…
Publication Type: Journal Article
Fire behaviour and smoke modelling: model improvement and measurement needs for next-generation smoke research and forecasting systems
Year: 2019
There is an urgent need for next-generation smoke research and forecasting (SRF) systems to meet the challenges of the growing air quality, health and safety concerns associated with wildland fire emissions. This review paper presents simulations and experiments of hypothetical prescribed burns with a suite of selected fire behaviour and smoke models and identifies major issues for model improvement and the most critical observational needs. The results are used to understand the new and improved capability required for the next-generation SRF systems and to support the design of the Fire and…
Publication Type: Journal Article
Wildland Fire Science Needs in Oregon and Washington: Local and regional research availability, applications, and gaps
Year: 2019
The Northwest Fire Science Consortium (Consortium) works to accelerate the awareness, understanding, and adoption of wildland fire science by connecting users in the Pacific Northwest with the most useful resources available. These efforts require an ongoing understanding of how users access wildland fire science, the challenges and opportunities that they experience in using different types of research, and topics where more information is needed. Previous research, including a prior assessment by the Consortium in 2011,1 has highlighted the importance of local or regionally-relevant…
Publication Type: Report
Assessing relative differences in smoke exposure from prescribed, managed, and full suppression wildland fire
Year: 2019
A novel approach is presented to analyze smoke exposure and provide a metric to quantify health-related impacts. Our results support the current understanding that managing low-intensity fire for ecological benefit reduces exposure when compared to a high-intensity full suppression fire in the Sierra Nevada of California. More frequent use of fire provides an opportunity to mitigate smoke exposure for both individual events and future emission scenarios. The differences in relative exposure between high-intensity, low-intensity, and prescribed burn were significant (P value < 0.01).…
Publication Type: Journal Article
Historical patterns of fire severity and forest structure and composition in a landscape structured by frequent large fires: Pumice Plateau ecoregion, Oregon, USA
Year: 2019
Context Lack of quantitative observations of extent, frequency, and severity of large historical fires constrains awareness of departure of contemporary conditions from those that demonstrated resistance and resilience to frequent fire and recurring drought. Objectives Compare historical and contemporary fire and forest conditions for a dry forest landscape with few barriers to fire spread. Methods Quantify differences in (1) historical (1700–1918) and contemporary (1985–2015) fire extent, fire rotation, and stand-replacing fire and (2) historical (1914–1924) and contemporary (2012) forest…
Publication Type: Journal Article
Fuel Characteristic Classification System (FCCS) field sampling and fuelbed development guide
Year: 2019
The Fuel Characteristic Classification System (FCCS) was designed to store and archive wildland fuel characteristics within fuelbeds, defined as the inherent physical characteristics of fuels that contribute to fire behavior and effects. The FCCS represents fuel characteristics in six strata including canopy, shrubs, herbaceous fuels, downed wood, litter-lichen-moss, and ground fuels. Each stratum is further divided into one or more categories and subcategories to represent the complexity of wildland and managed fuels. A variety of techniques to measure and summarize fuelbed data are detailed…
Publication Type: Report
Designing Operationally Relevant Daily Large Fire Containment Strategies Using Risk Assessment Results
Year: 2019
In this study, we aim to advance the optimization of daily large fire containment strategies for ground-based suppression resources by leveraging fire risk assessment results commonly used by fire managers in the western USA. We begin from an existing decision framework that spatially overlays fire risk assessment results with pre-identified potential wildland fire operational delineations (PODs), and then clusters PODs into a response POD (rPOD) using a mixed integer program (MIP) model to minimize expected loss. We improve and expand upon this decision framework through enhanced fire…
Publication Type: Journal Article
The influence of fire history on soil nutrients and vegetation cover in mixed-severity fire regime forests of the eastern Olympic Peninsula, Washington, USA
Year: 2018
The rain shadow forests of the Olympic Peninsula exemplify a mixed-severity fire regime class in the midst of a highly productive landscape where spatial heterogeneity of fire severity may have significant implications for below and aboveground post-fire recovery. The purpose of this study was to quantify the impacts of wildfire on forest soil carbon (C) and nitrogen (N) pools and assess the relationship of pyrogenic carbon (PyC) to soil processes in this mixed-severity ecosystem. We established a 112-year fire chronosequence with nine similar forest stands ranging in time since lastfire (TSF…
Publication Type: Journal Article
The Weather Conditions for Desired Smoke Plumes at a FASMEE Burn Site
Year: 2018
Weather is an important factor that determines smoke development, which is essential information for planning smoke field measurements. This study identifies the synoptic systems that would favor to produce the desired smoke plumes for the Fire and Smoke Model Evaluation Experiment (FASMEE). Daysmoke and PB-Piedmont (PB-P) models are used to simulate smoke plume evolution during the day time and smoke drainage and fog formation during the nighttime for hypothetical prescribed burns on 5–8 February 2011 at the Stewart Army Base in the southeastern United States. Daysmoke simulation is…
Publication Type: Journal Article
Long-Term Effects of Fire on Vegetation Structure and Predicted Fire Behavior in Wyoming Big Sagebrush Ecosystems
Year: 2018
Fire historically occurred across the sagebrush steppe, but little is known about how patterns of post-fire fuel accumulation influence future fire in Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) communities. To quantify change in fuel composition and structure in intact sagebrush ecosystems, we sampled 17 years following prescribed fire in eight approximately 400 ha plots (4 burned, 4 unburned control) at Hart Mountain National Antelope Refuge, OR, USA. Fuels data were used to model potential fire behavior in burn and control plots across four environmental scenarios that…
Publication Type: Journal Article
High-severity fire: Evaluating its key drivers and mapping its probability across western US forests
Year: 2018
Wildland fire is a critical process in forests of the western United States (US). Variation in fire behavior, which is heavily influenced by fuel loading, terrain, weather, and vegetation type, leads to heterogeneity in fire severity across landscapes. The relative influence of these factors in driving fire severity, however, is poorly understood. Here, we explore the drivers of high-severity fire for forested ecoregions in the western US over the period 2002–2015. Fire severity was quantified using a satellite-inferred index of severity, the relativized burn ratio. For each ecoregion, we…
Publication Type: Journal Article
Evidence for scale‐dependent topographic controls on wildfire spread
Year: 2018
Wildfire ecosystems are thought to be self‐regulated through pattern–process interactions between ignition frequency and location, and patterns of burned and recovering vegetation. Yet, recent increases in the frequency of large wildfires call into question the application of self‐organization theory to landscape resilience. Topography represents a stable bottom‐up template upon which fire interacts as both a physical and an ecological process. However, it is unclear how topographic control changes geographically and across spatial scales. We analyzed fire perimeter and topography data from…
Publication Type: Journal Article
Advancing the Science of Wildland Fire Dynamics Using Process-Based Models
Year: 2018
As scientists and managers seek to understand fire behavior in conditions that extend beyond the limits of our current empirical models and prior experiences, they will need new tools that foster a more mechanistic understanding of the processes driving fire dynamics and effects. Here we suggest that process-based models are powerful research tools that are useful for investigating a large number of emerging questions in wildland fire sciences. These models can play a particularly important role in advancing our understanding, in part, because they allow their users to evaluate the potential…
Publication Type: Journal Article
Pyro-Ecophysiology: Shifting the Paradigm of Live Wildland Fuel Research
Year: 2018
The most destructive wildland fires occur in mixtures of living and dead vegetation, yet very little attention has been given to the fundamental differences between factors that control their flammability. Historically, moisture content has been used to evaluate the relative flammability of live and dead fuels without considering major, unreported differences in the factors that control their variations across seasons and years. Physiological changes at both the leaf and whole plant level have the potential to explain ignition and fire behavior phenomena in live fuels that have been poorly…
Publication Type: Journal Article