Sensitivity Analysis of a Fire Spread Model in a Chaparral Landscape
Sensitivity Analysis of a Fire Spread Model in a Chaparral Landscape
复制标题
丛林景观中火灾蔓延模型的敏感性分析
DOI：
10.4996/fireecology.0401001
复制
发表时间：
2008
期刊：
影响因子：
5.1
通讯作者：
Max A. Moritz
中科院分区：
文献类型：
--
作者：
R. Clark;Allen Hope;Stefano Tarantola;Debora Gatelli;P. Dennison;Max A. Moritz
由于环境条件的独特组合，加州南部的查帕拉尔灌木丛容易发生大而强烈的野火。火灾研究界正在进行工作，以确定燃料积累或天气条件是否是大查帕拉尔火灾发生率的决定因素。本研究介绍了一个框架，有助于建模的角度来理解这些替代假设。由于模型使我们对火灾蔓延的物理过程的理解形式化，模型对气象和燃料输入的敏感性应该是其相对重要性的指标。基于Rothermel扩散方程，对HFire进行了全局敏感性分析（GSA），HFire是一个空间显式栅格模型，用于模拟查帕拉尔燃料中的火灾蔓延。GSA提供了一个定量测量的重要性，每个模型输入的预测火灾规模。结果表明，在极端天气条件下，风速对预测火灾规模的影响是任何其他单一模型输入的三倍以上。这一发现支持了这样一种观点，即在圣安娜条件下燃烧的火灾主要是由高风速驱动的。未来的研究将涉及扩展的GSA方法来量化这些投入的相对重要性，长期火灾制度在查帕拉尔生态系统。
Due to a unique combination of environmental conditions, the chaparral shrublands of southern California are prone to large, intense wildland fires. There is ongoing work in the fire research community to establish whether fuel accumulation or weather conditions are the determining factor in the prevalence of large chaparral fires. This study introduces a framework for contributing a modeling perspective to understanding these alternative hypotheses. As models formalize our understanding of the physical process of fire spread, the sensitivity of the models to the meteorological and fuel inputs should be indicators of their relative importance. A global sensitivity analysis (GSA) was conducted on HFire, a spatially explicit raster model developed for modeling fire spread in chaparral fuels, based on the Rothermel spread equations. The GSA provided a quantitative measure of the importance of each of the model inputs on the predicted fire size. The results indicate that, under extreme weather conditions, wind speed was over three times more influential on predicted fire sizes than any other single model input. This finding supports the idea that fires burning under Santa Ana conditions are primarily driven by high wind speeds. Future research will involve extending the GSA methodology to quantify the relative importance of these inputs in terms of the long-term fire regime in chaparral ecosystems.