Research Database
Displaying 201 - 220 of 223
Fuels and Fire Behavior Dynamics in Bark Beetle-Attacked Forests in Western North America and Implications for Fire Management
Year: 2012
Declining forest health attributed to associations between extensive bark beetle-caused tree mortality, accumulations of hazardous fuels, wildfire, and climate change have catalyzed changes in forest health and wildfire protection policies of land management agencies. These changes subsequently prompted research to investigate the extent to which bark beetle-altered fuel complexes affect fire behavior. Although not yet rigorously quantified, the results of the investigations, in addition to a growing body of operational experience and research, indicates that predictable changes in surface,…
Publication Type: Journal Article
Climate Change in Grasslands, Shrublands, and Deserts of the Interior American West: A Review and Needs Assessment
Year: 2012
Recent research and species distribution modeling predict large changes in the distributions of species and vegetation types in the western interior of the United States in response to climate change. This volume reviews existing climate models that predict species and vegetation changes in the western United States, and it synthesizes knowledge about climate change impacts on the native fauna and flora of grasslands, shrublands and deserts of the interior American West. Species' responses will depend not only on their physiological tolerances but also on their phenology, establishment…
Publication Type: Report
Climate Change and Disruptions to Global Fire Activity
Year: 2012
Future disruptions to fire activity will threaten ecosystems and human well-being throughout the world, yet there are few fire projections at global scales and almost none from a broad range of global climate models (GCMs). Here we integrate global fire datasets and environmental covariates to build spatial statistical models of fire probability at a 0.58 resolution and examine environmental controls on fire activity. Fire models are driven by climate norms from 16 GCMs (A2 emissions scenario) to assess the magnitude and direction of change over two time periods, 2010–2039 and 2070–2099. From…
Publication Type: Journal Article
Projecting future distributions of ecosystem climate niches: Uncertainties and management applications
Year: 2012
Projecting future distributions of ecosystems or species climate niches has widely been used to assess the potential impacts of climate change. However, variability in such projections for the future periods, particularly the variability arising from uncertain future climates, remains a critical challenge for incorporating these projections into climate change adaptation strategies. We combined the use of a robust statistical modeling technique with a simple consensus approach consolidating projected outcomes for multiple climate change scenarios, and exemplify how the results could guide…
Publication Type: Journal Article
Afternoon Rain More Likely Over Drier Soils
Year: 2012
Land surface properties, such as vegetation cover and soil moisture, influence the partitioning of radiative energy between latent and sensible heat fluxes in daytime hours. During dry periods, soil-water deficit can limit evapotranspiration, leading to warmer and drier conditions in the lower atmosphere. Soil moisture can influence the development of convective storms through such modifications of low-level atmospheric temperature and humidity, which in turn feeds back on soil moisture. Yet there is considerable uncertainty in how soil moisture affects convective storms across the world,…
Publication Type: Journal Article
Fourmile Canyon Fire Findings
Year: 2012
The Fourmile Canyon Fire burned in the fall of 2010 in the Rocky Mountain Front Range adjacent to Boulder, Colorado. The fire occurred in steep, rugged terrain, primarily on privately owned mixed ponderosa pine and Douglas-fir forests. The fire started on September 6 when the humidity of the air was very dry (≈ <7%) and the winds were steadily blowing in the range of 15 miles per hour and gusting to over 40 miles per hour. These conditions prevailed for most of the first day when the fire burned approximately 5,700 acres and destroyed 162 homes. Because of the windy conditions, aircraft…
Publication Type: Report
Pattern and process of prescribed fires influence effectiveness at reducing wildfire severity in dry coniferous forests
Year: 2012
We examined the effects of three early season (spring) prescribed fires on burn severity patterns of summer wildfires that occurred 1–3 years post- treatment in a mixed conifer forest in central Idaho. Wildfire and prescribed fire burn severities were estimated as the difference in normalized burn ratio (dNBR) using Landsat imagery. We used GIS derived vegetation, topography, and treatment variables to generate models predicting the wildfire burn severity of 1286–5500 30- m pixels within and around treated areas. We found that wildfire severity was significantly lower in treated areas than in…
Publication Type: Journal Article
Advancing effects analysis for integrated, large-scale wildfire risk assessment
Year: 2011
In this article, we describe the design and development of a quantitative, geospatial risk assessment tool intended to facilitate monitoring trends in wildfire risk over time and to provide information useful in prioritizing fuels treatments and mitigation measures. The research effort is designed to develop, from a strategic view, a first approximation of how both fire likelihood and intensity influence risk to social, economic, and ecological values at regional and national scales. Three main components are required to generate wildfire risk outputs: (1) burn probability maps generated from…
Publication Type: Journal Article
Simulating fuel treatment effects in dry forests of the western United States: testing the principles of a fire-safe forest
Year: 2011
We used the Fire and Fuels Extension to the Forest Vegetation Simulator (FFE-FVS) to simulate fuel treatment effects on 45 1 62 stands in low- to midelevation dry forests (e.g., ponderosa pine (Pinus ponderosa Doug!. ex. P. & C. Laws.) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) of the western United States. We evaluated treatment effects on predicted post-treatment fire behavior (fire type) and fire hazard (torching index). FFE-FVS predicts that thinning and surface fuel treatments reduced crown fire behavior relative to no treatment; a large proportion of stands were…
Publication Type: Journal Article
Synthesis of Knowledge of Extreme Fire Behavior: Volume I for Fire Managers
Year: 2011
The National Wildfire Coordinating Group definition of extreme fire behavior (EFB) indicates a level of fire behavior characteristics that ordinarily precludes methods of direct control action. One or more of the following is usually involved: high rate of spread, prolific crowning/spotting, presence of fire whirls, and strong convection column. Predictability is difficult because such fires often exercise some degree of influence on their environment and behave erratically, sometimes dangerously. Alternate terms include “blow up” and “fire storm.” Fire managers examining fires over the last…
Publication Type: Report
Northwest Forest Plan -- The First 15 Years: Status and Trends of Northern Spotted Owl Populations and Habitats
Year: 2011
This is the second in a series of periodic monitoring reports on northern spotted owl (Strix occidentalis caurina) population and habitat trends on federally administered lands since implementation of the Northwest Forest Plan in 1994.Here we summarize results from a population analysis that included data from long-term demographic studies during 1985–2008. This data was analyzed separately by study area, and also in a meta-analysis across all study areas to assess temporal and spatial patterns in fecundity, apparent survival, recruitment, and annual rates of population change. Estimated…
Publication Type: Report
Wildfire Risk Management on a Landscape with Public and Private Ownership: Who Pays for Protection?
Year: 2010
Wildfire, like many natural hazards, affects large landscapes with many landowners and the risk individual owners face depends on both individual and collective protective actions. In this study, we develop a spatially explicit game theoretic model to examine the strategic interaction between landowners’ hazard mitigation decisions on a landscape with public and private ownership. We find that in areas where ownership is mixed, the private landowner performs too little fuel treatment as they ‘‘free ride’’—capture benefits without incurring the costs—on public protection, while areas with…
Publication Type: Journal Article
Introducing FuelCalc: A New Tool that Helps Turn Static Inventory Data into Actionable Information
Year: 2010
Fuel and fire managers perform fuel treatments to manage and restore ecosystems and protect resources. In order to plan effective fuel treatments that accomplish objectives, managers need to analyze fuel conditions and document the expected fire behavior and fire effects both before and after fuel treatment. To help accomplish these goals, a new software tool named FuelCalc was created. FuelCalc facilitates use of a wide range of inventory data and fuel characteristics to help calculate fuel quantities and qualities to estimate potential fire behavior, fire effects, and smoke production. By…
Publication Type: Report
FOFEM: The First-Order Fire Effects Model Adapts to the 21st Century
Year: 2009
Technology is playing an increasingly pivotal role in the efficiency and effectiveness of fire management. The First Order Fire Effects Model (FOFEM) is a widely used computer application that predicts the immediate or ‘first-order’ effects of fire: fuel consumption, tree mortality, emissions, and soil heating. FOFEM’s simple operation and comprehensive features have made it a workhorse for fire and resource professionals who need to be able to predict, assess and plan for fire’s effects. Over the last decade FOFEM has undergone several upgrades as developers continue to improve function and…
Publication Type: Report
Consume 3.0 -- A Software Tool for Computing Fuel Consumption
Year: 2009
Knowing when, where and how fire should be applied is critical for land managers planning to use fire prescriptively for land management goals, or allowing fires ignited naturally to burn. Myriad variables need to be taken into consideration to determine how fire will consume different fuels. Consume, version 3.0 is a user-friendly software that incorporates the Fuel Characteristic Classification System (FCCS) to predict fuel consumption, pollutant emissions, and heat release. A flexible tool, Consume 3.0 makes these calculations based on fuel loadings, fuel moisture and other environmental…
Publication Type: Report
ArcFuels: Integrating Wildfire Models and Risk Analysis into Landscape Fuels Management
Year: 2009
That risk from wildfire continues to grow across the United States is not a new problem. Managing forest fuels in the real world—such as thinning and burning prescriptively—to reduce fuel loads have been used effectively to reduce the risk of severe wildfire. These actions have been helped by a variety of software tools that assist managers in planning and evaluating fuel treatments to ensure they are cost effective in terms of impeding the growth of future large, severe wildfires. While many landscape planning tools do a fine job within the scope of their capabilities, the process of fine…
Publication Type: Report
Assessing fuel treatment effectiveness using satellite imagery and spatial statistics
Year: 2009
Understanding the influences of forest management practices on wildfire severity is critical in fire-prone ecosystems of the western United States. Newly available geospatial data sets characterizing vegetation, fuels, topography, and burn severity offer new opportunities for studying fuel treatment effectiveness at regional to national scales. In this study, we used ordinary least-squares (OLS) regression and sequential autoregression (SAR) to analyze fuel treatment effects on burn severity for three recent wildfires: the Camp 32 fire in western Montana, the School fire in southeastern…
Publication Type: Journal Article
The evaluation of meta-analysis techniques for quantifying prescribed fire effects on fuel loadings
Year: 2009
Models and effect-size metrics for meta-analysis were compared in four separate meta-analyses quantifying surface fuels after prescribed fires in ponderosa pine (Pinus ponderosa Dougl. ex Laws.) forests of the Western United States. An aggregated data set was compiled from 8 published reports that contained data from 65 fire treatment units. Downed woody and organic fuels were partitioned into five classes, and four meta-analyses were performed on each in a 2 by 2 factorial combination of fixed-effects vs. mixed-effects models with a difference-based metric (Hedges’ d) vs. a ratio-based…
Publication Type: Report
Has Fire Suppression Increased the Amount of Carbon Stored in Western US Forests?
Year: 2008
Active 20th century fire suppression in western US forests, and a resulting increase in stem density, is thought to account for a significant fraction of the NorthAmerican carbon sink. We compared California forest inventories from the 1930s with inventories from the 1990s to quantify changes in aboveground biomass. Stem density in mid-montane conifer forests increased by 34%, while live aboveground carbon stocks decreased by 26%. Increased stem density reflected an increase in the number of small trees and a net loss of large trees. Large trees contain a disproportionate amount of carbon,…
Publication Type: Journal Article
Behavior Modification: Tempering Fire at the Landscape Level
Year: 2008
With a history of management choices that have suppressed fire in the West, ecosystems in which fire would play a vital role have developed tremendous fuel loads. As a result, conditions are prime for fires to grow large, escape attack measures, and become catastrophic conflagrations that damage watersheds, forest resources, and homes. With a quiver of treatment options, land managers have successfully used prescribed burning and thinning to modify landscapes at the stand level. But planning treatments to modify fuel build up on a patch of forest is vastly different than planning treatments…
Publication Type: Report