Landscape-Level Measurements of and Controls on Wildfire Spread Rates

国家科学基础地理空间科学(GSS)进展这项研究项目将为野火的传播、其传播的物理机制以及风、地形和燃料特性如何影响其传播贡献新的知识。观察和分析野火锋面移动的速度是具有挑战性的，因为野火的短暂、危险的性质以及它们发生的空间不均匀条件。该项目将通过开发一种新的方法，从精确排列的机载热红外图像中划定火锋并测量其运动，从而增强推断火势蔓延速度和风速的能力。这些对火灾蔓延速度的测量和分析不可能达到了解火灾行为及其与燃料特性、地形和风等因素的关系所需的规模。这项研究的结果将支持更可持续的火灾实践。测量和生成有关野火蔓延速度和控制的知识将使火灾科学和火灾管理界以及世界各地的应急响应管理人员受益。野火蔓延速度是灭火和疏散的关键信息要求。它们的测量和预测构成了一个关键的科学挑战。观察和分析野火锋面的移动速度是具有挑战性的，因为野火的瞬变、危险的性质，以及它们发生的空间不均匀条件。为了应对这些挑战，调查人员将使用机载热红外成像技术，频繁而详细地跟踪南加州查帕尔植被区域内移动的火焰锋面。飞行线将沿着最大扩散区附近的火焰锋面方向排列。沿着飞行路线拍摄的频繁、连续的图像将使人们能够通过图像流动分析技术来估计风速。将使用空间统计和地理可视化方法分析火线段，以经验地建立野火传播率与景观尺度上植被燃料、地形和风的特征或条件之间的关系。对更广泛社区的项目好处将包括更好的工具来评估火灾行为，以及更好地估计野火对燃料条件和处理的反应。

NATIONAL SCIENCE FOUNDATIONGEOGRAPHY SPATIAL SCIENCES (GSS) PROGRAMABSTRACTThis research project will contribute new knowledge regarding wildfires spread, the physical mechanisms through which they spread, and how wind, topography, and fuel properties affect their propagation. Observation and analyses of how fast a wildfire front travels is challenging because of the transient, hazardous nature of wildfires and the spatially heterogeneous conditions in which they occur. The project will enhance capabilities for inferring fire-spread rates and wind speeds by developing a new approach for delineating fire fronts and measuring their movements from precisely aligned airborne thermal infrared images. These measurements and analyses of fire-spread rates have not been possible at scales that are needed to understand fire behavior and its relationship to factors like fuel properties, topography, and wind. Outcomes from this research will support more sustainable fire practices. Measuring and generating knowledge about rates of and controls on wildfire spread will benefit the fire-science and fire-management communities as well as emergency response managers throughout the world.Wildfire-spread rates are key information requirements for fire suppression and evacuations. Their measurement and prediction pose a critical scientific challenge. Observing and analyzing how fast a wildfire front is traveling is challenging due to the transient, hazardous nature of wildfires and the spatially heterogeneous conditions in which they occur. To address these challenges, the investigators will use airborne thermal infrared imaging to acquire frequent and detailed tracking of moving flaming fronts for an area of chaparral vegetation in southern California. The flight lines will be aligned along the direction of the flaming front in the vicinity of the maximum spread zone. Frequent, sequential images captured along flight lines will enable wind speeds to be estimated through image flow analysis techniques. Segments of the fire line will be analyzed using spatial statistical and geovisualization methods to empirically establish the relationships between the rate of wildfire spread and characteristics or conditions of the vegetation fuels, terrain, and wind at the landscape scale. Project benefits to the broader community will include better tools to evaluate fire behavior and better estimates of the response of wildfires to fuel conditions and treatments.