Research Database
Displaying 101 - 106 of 106
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
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
The relationship of large fire occurrence with drought and fire danger indices in the western USA, 1984-2008: the role of temporal scale
Year: 2013
The relationship between large fire occurrence and drought has important implications for fire prediction under current and future climates. This study’s primary objective was to evaluate correlations between drought and fire-danger-rating indices representing short- and long-term drought, to determine which had the strongest relationships with large fire occurrence at the scale of the western United States during the years 1984–2008. We combined 4–8-km gridded drought and fire-danger-rating indices with information on fires greater than 404.7 ha (1000 acres). To account for differences in…
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