Research Database
Displaying 81 - 86 of 86
Topography, fuels, and fire exclusion drive fire severity of the Rim Fire in an old-growth mixed-conifer forest, Yosemite National Park, USA
Year: 2015
The number of large, high-severity fires has increased in the western United States over the past 30 years due to climate change and increasing tree density from fire suppression. Fuel quantity, topography, and weather during a burn control fire severity, and the relative contributions of these controls in mixed-severity fires in mountainous terrain are poorly understood. In 2013, the Rim Fire burned a previously studied 2125 ha area of mixed-conifer forest in Yosemite National Park. Data from 84 plots sampled in 2002 revealed increases in tree density, basal area, and fuel buildup since 1899…
Publication Type: Journal Article
Operational wildfire suppression modelling: a review evaluating development, state of the art and future directions
Year: 2015
Wildfires are an inherent part of the landscape in many parts of the world; however, they often impose substantial economic burdens on human populations where they occur, both in terms of impacts and of management costs. As wildfires burn towards human assets, a universal response has been to deploy fire suppression resources (crews, vehicles and aircraft) to extinguish them, and limit their spread or impacts. The determination of the appropriate levels of investment, resource allocation and suppression tactics is a challenge for managers. As suppression expenses account for a substantial…
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
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
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 resultingincrease in stem density, is thought to account for a significant fraction of the NorthAmerican carbon sink. We compared California forest inventories from the 1930s withinventories from the 1990s to quantify changes in aboveground biomass. Stem density inmid-montane conifer forests increased by 34%, while live aboveground carbon stocksdecreased by 26%. Increased stem density reflected an increase in the number of smalltrees and a net loss of large trees. Large trees contain a disproportionate amount ofcarbon, and the…
Publication Type: Journal Article
Smoke on the hill: A comparative study of wildfire and two communities
Year: 2003
Wildfire represents a serious challenge to communities in the rural West. After decades of fire suppression, land managers now perceive a greater role for wildfire in the ecosystem. In the meantime, migration patterns from urban to rural settings have increased the number of people living in forested areas throughout the West, therefore; wildfires are a threat to more homes than ever in the region. This study focuses on two communities’ response to wildfires during the intense fire season of 1994. Through qualitative research methods, the study analyzes these diverse responses in the context…
Publication Type: Journal Article