Wildfire Risk to Communities Burn Probability (Image Service)

The data included in this publication depict the 2024 version of components of wildfire risk for all lands in the United States that: 1) are landscape-wide (i.e., measurable at every pixel across the landscape); and 2) represent in situ risk - risk at the location where the adverse effects take place on the landscape.National wildfire hazard datasets of annual burn probability and fire intensity, generated by the USDA Forest Service, Rocky Mountain Research Station and Pyrologix LLC, form the foundation of the Wildfire Risk to Communities data. Vegetation and wildland fuels data from LANDFIRE 2020 (version 2.2.0) were used as input to two different but related geospatial fire simulation systems. Annual burn probability was produced with the USFS geospatial fire simulator (FSim) at a relatively coarse cell size of 270 meters (m). To bring the burn probability raster data down to a finer resolution more useful for assessing hazard and risk to communities, we upsampled them to the native 30 m resolution of the LANDFIRE fuel and vegetation data. In this upsampling process, we also spread values of modeled burn probability into developed areas represented in LANDFIRE fuels data as non-burnable. Burn probability rasters represent landscape conditions as of the end of 2020. Fire intensity characteristics were modeled at 30 m resolution using a process that performs a comprehensive set of FlamMap runs spanning the full range of weather-related characteristics that occur during a fire season and then integrates those runs into a variety of results based on the likelihood of those weather types occurring. Before the fire intensity modeling, the LANDFIRE 2020 data were updated to reflect fuels disturbances occurring in 2021 and 2022. As such, the fire intensity datasets represent landscape conditions as of the end of 2022. Additional methodology documentation is provided in a methods document (\Supplements\WRC_V2_Methods_Landscape-wideRisk.pdf) packaged in the data download.The specific raster datasets in this publication include:Risk to Potential Structures (RPS): A measure that integrates wildfire likelihood and intensity with generalized consequences to a home on every pixel. For every place on the landscape, it poses the hypothetical question, "What would be the relative risk to a house if one existed here?" This allows comparison of wildfire risk in places where homes already exist to places where new construction may be proposed. This dataset is referred to as Risk to Homes in the Wildfire Risk to Communities web application.Conditional Risk to Potential Structures (cRPS): The potential consequences of fire to a home at a given location, if a fire occurs there and if a home were located there. Referred to as Wildfire Consequence in the Wildfire Risk to Communities web application.Exposure Type: Exposure is the spatial coincidence of wildfire likelihood and intensity with communities. This layer delineates where homes are directly exposed to wildfire from adjacent wildland vegetation, indirectly exposed to wildfire from indirect sources such as embers and home-to-home ignition, or not exposed to wildfire due to distance from direct and indirect ignition sources.Burn Probability (BP): The annual probability of wildfire burning in a specific location. Referred to as Wildfire Likelihood in the Wildfire Risk to Communities web application.Conditional Flame Length (CFL): The mean flame length for a fire burning in the direction of maximum spread (headfire) at a given location if a fire were to occur; an average measure of wildfire intensity.Flame Length Exceedance Probability - 4 ft (FLEP4): The conditional probability that flame length at a pixel will exceed 4 feet if a fire occurs; indicates the potential for moderate to high wildfire intensity.Flame Length Exceedance Probability - 8 ft (FLEP8): the conditional probability that flame length at a pixel will exceed 8 feet if a fire occurs; indicates the potential for high wildfire intensity.Wildfire Hazard Potential (WHP): An index that quantifies the relative potential for wildfire that may be difficult to manage, used as a measure to help prioritize where fuel treatments may be needed.Additional methodology documentation is provided with the data publication download. Metadata and Downloads.Note: Pixel values in this image service have been altered from the original raster dataset due to data requirements in web services. The service is intended primarily for data visualization. Relative values and spatial patterns have been largely preserved in the service, but users are encouraged to download the source data for quantitative analysis.This record was taken from the USDA Enterprise Data Inventory that feeds into the https://data.gov catalog. Data for this record includes the following resources: ISO-19139 metadata ArcGIS Hub Dataset ArcGIS GeoService For complete information, please visit https://data.gov.

本出版物所包含的数据描绘了美国所有土地上2024版本的森林火灾风险组成部分，包括：1）景观范围内的数据（即在景观的每个像素上均可测量）；2）表示现场风险——即在景观上发生不利影响的位置所面临的风险。美国国家森林火灾危害数据集，包括年度燃烧概率和火灾强度，由美国农业部森林服务局、落基山脉研究站和Pyrologix LLC生成，构成了社区森林火灾风险数据的基础。LANDFIRE 2020（版本2.2.0）中的植被和野地燃料数据被用作两个不同但相关的地理空间火灾模拟系统的输入。年度燃烧概率使用美国森林服务局的地理空间火灾模拟器（FSim）以相对较粗的270米（m）单元格大小生成。为了将燃烧概率栅格数据提升至更细的分辨率，以便更有效地评估灾害和风险，我们将它们上采样到LANDFIRE燃料和植被数据的原生30米分辨率。在此上采样过程中，我们还把模拟的燃烧概率值传播到LANDFIRE燃料数据中代表的不燃开发区域。燃烧概率栅格数据表示截至2020年底的景观条件。使用一个执行一系列FlamMap运行的过程，该过程覆盖了火灾季节中发生的所有与天气相关的特征的全范围，并将这些运行整合到基于这些天气类型发生概率的各种结果中，以30米分辨率的精度模拟了火灾强度特征。在火灾强度建模之前，LANDFIRE 2020数据已更新以反映2021年和2022年发生的燃料扰动。因此，火灾强度数据集表示截至2022年底的景观条件。附加的方法论文档包含在数据下载中的方法文档（SupplementsWRC_V2_Methods_Landscape-wideRisk.pdf）。本出版物中的特定栅格数据集包括：潜在结构风险（RPS）：一个综合森林火灾可能性和强度以及每个像素上住宅的广义后果的度量。对于景观上的每个地方，它提出一个假设性问题：“如果在这里存在一栋房子，那么相对风险会是多少？”这允许比较现有住宅的森林火灾风险与可能提议新建筑的地方的森林火灾风险。该数据集在社区森林火灾风险网络应用中被称作房屋风险。条件潜在结构风险（cRPS）：在给定位置，如果发生火灾并且该位置有住宅，火灾对住宅可能造成的潜在后果。在社区森林火灾风险网络应用中被称为森林火灾后果。暴露类型：暴露是森林火灾可能性和强度与社区的时空巧合。这一层描绘了住宅直接暴露于邻近的野地植被引发的森林火灾，间接暴露于来自如火星和住宅间引燃等间接源的森林火灾，或者由于与直接和间接点火源的距离而未暴露于森林火灾的情况。燃烧概率（BP）：在特定地点发生森林火灾的年度概率。在社区森林火灾风险网络应用中被称作森林火灾可能性。条件火焰长度（CFL）：如果发生火灾，在给定位置沿着最大蔓延方向（前锋）燃烧的火焰的平均长度；是森林火灾强度的平均度量。火焰长度超过概率 - 4英尺（FLEP4）：如果发生火灾，像素处的火焰长度超过4英尺的条件概率；表明中等到高森林火灾强度的可能性。火焰长度超过概率 - 8英尺（FLEP8）：如果发生火灾，像素处的火焰长度超过8英尺的条件概率；表明高森林火灾强度的可能性。森林火灾危害潜力（WHP）：一个量化难以管理的森林火灾相对潜力的指数，用作确定燃料处理可能需要的优先级的度量。数据出版时还提供了附加的方法论文档。元数据和下载。注意：由于网络服务的数据要求，此图像服务中的像素值已从原始栅格数据集中修改。该服务主要旨在数据可视化。服务中保留了相对值和空间模式，但鼓励用户下载源数据以进行定量分析。此记录取自为https://data.gov目录提供数据的美国农业部企业数据库存。此记录的数据包括以下资源：ISO-19139元数据、ArcGIS Hub数据集、ArcGIS GeoService。如需完整信息，请访问https://data.gov。