Research Database
Displaying 201 - 220 of 240
Defining extreme wildland fires using geospatial and ancillary metrics
Year: 2014
There is a growing professional and public perception that ‘extreme’ wildland fires are becoming more common due to changing climatic conditions. This concern is heightened in the wildland–urban interface where social and ecological effects converge. ‘Mega-fires’, ‘conflagrations’, ‘extreme’ and ‘catastrophic’ are descriptors interchangeably used increasingly to describe fires in recent decades in the US and globally. It is necessary to have consistent, meaningful and quantitative metrics to define these perceived ‘extreme’ fires, given studies predict an increased frequency of large and…
Publication Type: Journal Article
Wildland fire emissions, carbon, and climate: Modeling fuel consumption
Year: 2014
Fuel consumption specifies the amount of vegetative biomass consumed during wildland fire. It is a two-stage process of pyrolysis and combustion that occurs simultaneously and at different rates depending on the characteristics and condition of the fuel, weather, topography, and in the case of prescribed fire, ignition rate and pattern. Fuel consumption is the basic process that leads to heat absorbing emissions called greenhouse gas and other aerosol emissions that can impact atmospheric and ecosystem processes, carbon stocks, and land surface reflectance. It is a critical requirement for…
Publication Type: Journal Article
Modeling Regional-Scale Wildland Fire Emissions with the Wildland Fire Emissions Information System
Year: 2014
As carbon modeling tools become more comprehensive, spatial data are needed to improve quantitative maps of carbon emissions from fire.The Wildland Fire Emissions Information System (WFEIS) provides mapped estimates of carbon emissions from historical forest fires in the United States through a web browser. WFEIS improves access to data and provides a consistent approach to estimating emissions at landscape, regional, and continental scales. The system taps into data and tools developed by the U.S. Forest Serviceto describe fuels, fuel loadings, and fuel consumption and merges information…
Publication Type: Journal Article
Wildland firefighter safety zones: a review of past science and summary of future needs
Year: 2014
Current wildland firefighter safety zone guidelines are based on studies that assume flat terrain, radiant heating, finite flame width, constant flame temperature and high flame emissivity. Firefighter entrapments and injuries occur across a broad range of vegetation, terrain and atmospheric conditions generally when they are within two flame heights of the fire. Injury is not confined to radiant heating or flat terrain; consequently, convective heating should be considered as a potential heating mode. Current understanding of energy transport in wildland fires is briefly summarised, followed…
Publication Type: Journal Article
The role of defensible space for residential structure protection during wildfires
Year: 2014
With the potential for worsening fire conditions, discussion is escalating over how to best reduce effects on urban communities. A widely supported strategy is the creation of defensible space immediately surrounding homes and other structures. Although state and local governments publish specific guidelines and requirements, there is little empirical evidence to suggest how much vegetation modification is needed to provide significant benefits. We analysed the role of defensible space by mapping and measuring a suite of variables on modern pre-fire aerial photography for 1000 destroyed and…
Publication Type: Journal Article
Understanding evacuation preferences and wildfire mitigations among Northwest Montana residents
Year: 2014
There is currently insufficient information in the United States about residents’ planned evacuation actions during wildfire events, including any intent to remain at or near home during fire events. This is incompatible with growing evidence that select populations at risk from wildfire are considering alternatives to evacuation. This study explores the evacuation preferences of wildland–urban interface residents in Flathead County, Montana, USA. We compare the performance of wildfire mitigation and fuel reduction actions across groups of residents with different primary evacuation…
Publication Type: Journal Article
Briefing: Climate and Wildfire in Western U.S. Forests
Year: 2014
Wildfire in western U.S. federally managed forests has increased substantially in recent decades, with large (>1000 acre) fires in the decade through 2012 over five times as frequent (450 percent increase) and burned area over ten times as great (930 percent increase) as the 1970s and early 1980s. These changes are closely linked to increased temperatures and a greater frequency and intensity of drought. Projected additional future warming implies that wildfire activity may continue to increase in western forests. However, the interaction of changes in climate, fire and other disturbances…
Publication Type: Conference Proceedings
Correlations between components of the water balance and burned area reveal insights for predicting forest fire area in the southwest United States
Year: 2014
We related measurements of annual burned area in the southwest United States during 1984–2013 to records of climate variability. Within forests, annual burned area correlated at least as strongly with spring–summer vapour pressure deficit (VPD) as with 14 other drought-related metrics, including more complex metrics that explicitly represent fuel moisture. Particularly strong correlations with VPD arise partly because this term dictates the atmospheric moisture demand. Additionally, VPD responds to moisture supply, which is difficult to measure and model regionally due to complex…
Publication Type: Journal Article
Fuel treatment prescriptions alter spatial patterns of fire severity around the wildland-urban interface during the Wallow Fire, Arizona, USA
Year: 2014
Fuel reduction treatments are implemented in the forest surrounding the wildland–urban interface (WUI) to provide defensible space and safe opportunity for the protection of homes during a wildfire. The 2011 Wallow Fire in Arizona USA burned through recently implemented fuel treatments in the wildland surrounding residential communities in the WUI, and those fuel treatments have been credited with providing firefighter opportunities to protect residences during the Wallow Fire and thereby preventing the loss of homes that otherwise would have been burned. To characterize the spatial pattern…
Publication Type: Journal Article
Mathematical model and sensor development for measuring energy transfer from wildland fires
Year: 2014
Current practices for measuring high heat flux in scenarios such as wildland forest fires use expensive, thermopile-based sensors, coupled with mathematical models based on a semi-infinite-length scale. Although these sensors are acceptable for experimental testing in laboratories, high error rates or the need for water cooling limits their applications in field experiments. Therefore, a one-dimensional, finite-length scale, transient-heat conduction model was developed and combined with an inexpensive, thermocouple-based rectangular sensor, to create a rapidly deployable, non-cooled sensor…
Publication Type: Journal Article
Learning to coexist with wildfire
Year: 2014
The impacts of escalating wildfire in many regions — the lives and homes lost, the expense of suppression and the damage to ecosystem services — necessitate a more sustainable coexistence with wildfire. Climate change and continued development on fire-prone landscapes will only compound current problems. Emerging strategies for managing ecosystems and mitigating risks to human communities provide some hope, although greater recognition of their inherent variation and links is crucial. Without a more integrated framework, fire will never operate as a natural ecosystem process, and the impact…
Publication Type: Journal Article
Wildfire evacuation and its alternatives: perspectives from four United States' communities
Year: 2014
Recent years have seen growing interest within the United States fire management community in exploring alternatives to the standard approach of evacuating entire populations that are threatened by a wildfire. There has been particular interest in what can be learned from the Australian approach, whereby residents choose whether or not to evacuate under the ‘prepare, stay and defend or leave early’ approach, also called Stay or Go. Given these developments, it is useful to understand what elements are taken into consideration by those who would be most affected by a new approach when they…
Publication Type: Journal Article
Allowing a wildfire to burn: estimating the effect on future suppression costs
Year: 2013
Where a legacy of aggressive wildland fire suppression has left forests in need of fuel reduction, allowing wildland fire to burn may provide fuel treatment benefits, thereby reducing suppression costs from subsequent fires. The least-cost-plus-net-value-change model of wildland fire economics includes benefits of wildfire in a framework for evaluating suppression options. In this study, we estimated one component of that benefit – the expected present value of the reduction in suppression costs for subsequent fires arising from the fuel treatment effect of a current fire. To that end, we…
Publication Type: Journal Article
Social Science at the WUI: A Compendium of Research Results to Create Fire-Adapted Communities
Year: 2013
Over the past decade, a growing body of research has been conducted on the human dimensions of wildland fire. Building on a relatively small number of foundational studies, this research now addresses a wide range of topics including mitigation activities on private lands, fuels reduction treatments on public land, community impacts and resident behaviors during fire, acceptance of approaches to postfire restoration and recovery, and fire management policy and decision making. As this research has matured, there has been a recognition of the need to examine the full body of resulting…
Publication Type: Report
Wildland Fire management: Are actively managed forests more resilient than passively managed forests?
Year: 2013
Large areas of federal lands in the western states are currently at high risk of severe wildfire and have many insect and disease problems, indicating a significant decline in forest health and resilience. Although research studies have not been done that would measure whether actively managed forests are more resilient to wildfires than passively managed forests, results from studies of hazardous fuels treatment effectiveness and the economic benefits from avoided costs of future wildfire suppression due to fuels treatment can be used to support an affirmative reply to the question. If a…
Publication Type: Report
Modelling conditional burn probability patterns for large wildland fires
Year: 2013
We present a technique for modelling conditional burn probability patterns in two dimensions for large wildland fires. The intended use for the model is strategic program planning when information about future fire weather and event durations is unavailable and estimates of the average probabilistic shape and extent of large fires on a landscape are needed. To model average conditional burn probability patterns, we organised historical fire data from Yellowstone National Park, USA, into a set of grids; one grid per fire. We captured various spatial relationships inherent in the gridded data…
Publication Type: Journal Article
Lessons Learned from Waldo Canyon: FAC mitigation assessment team report
Year: 2013
The Waldo Canyon fire presented the first opportunity for partners in the national Fire Adapted Communities (FAC) Coalition to collectively assess the performance of mitigation practices in Colorado Springs in a post-fire environment and to compare the results to the mitigation strategy recommended by the Fire Adapted Communities program. The assessment was conducted from July 18-20, 2012, by a FAC Wildfire Mitigation Assessment Team, which included two sets of researchers: structural assessment and forestry experts and social science and public education experts, accompanied by staff from…
Publication Type: Report
Overcoming barriers to firewise actions by residents
Year: 2013
Encouraging the public to take action (e.g., creating defensible space) that can reduce the likelihood of wildfire damage and decrease the likelihood of injury is a common approach to increasing wildfire safety and damage mitigation. This study was designed to improve our understanding of both individual and community actions that homeowners currently do or might take to protect their home or property, and the barriers that impede homeowners from completing firewise treatments to their home or property.
Publication Type: Report
Wildland firefighter entrapment avoidance: modelling evacuation triggers
Year: 2013
Wildland firefighters are often called on to make tactical decisions under stressful conditions in order to suppress a fire. These decisions can be hindered by human factors such as insufficient knowledge of surroundings and conditions, lack of experience, overextension of resources or loss of situational awareness. One potential tool for assisting fire managers in situations where human factors can hinder decision-making is the Wildland–Urban Interface Evacuation (WUIVAC) model, which models fire minimum travel times to create geographic trigger buffers for evacuation recommendations.…
Publication Type: Journal Article
Wildfire, Wildlands, and People: Understanding and preparing for wildfire in the wildland-urban interface
Year: 2013
Fire has historically played a fundamental ecological role in many of America’s wildland areas. However, the rising number of homes in the wildland-urban interface (WUI), associated impacts on lives and property from wildfire, and escalating costs of wildfire management have led to an urgent need for communities to become "fire-adapted." We present maps of the conterminous United States that illustrate historical natural fire regimes, the wildland-urban interface, and the number and location of structures burned since 1999. We outline a sampler of actions, programs, and community planning and…
Publication Type: Report