Wildfire Risk to Communities Housing Unit Density (Image Service)

The data included in this publication depict components of wildfire risk specifically for populated areas in the United States. These datasets represent where people live in the United States and the in situ risk from wildfire, i.e., the risk at the location where the adverse effects take place.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. The data products in this publication that represent where people live, reflect 2021 estimates of housing unit and population counts from the U.S. Census Bureau, combined with building footprint data from Onegeo and USA Structures, both reflecting 2022 conditions.The specific raster datasets included in this publication include:Building Count: Building Count is a 30-m raster representing the count of buildings in the building footprint dataset located within each 30-m pixel.Building Density: Building Density is a 30-m raster representing the density of buildings in the building footprint dataset (buildings per square kilometer [km²]).Building Coverage: Building Coverage is a 30-m raster depicting the percentage of habitable land area covered by building footprints.Population Count (PopCount): PopCount is a 30-m raster with pixel values representing residential population count (persons) in each pixel.Population Density (PopDen): PopDen is a 30-m raster of residential population density (people/km²).Housing Unit Count (HUCount): HUCount is a 30-m raster representing the number of housing units in each pixel.Housing Unit Density (HUDen): HUDen is a 30-m raster of housing-unit density (housing units/km²).Housing Unit Exposure (HUExposure): HUExposure is a 30-m raster that represents the expected number of housing units within a pixel potentially exposed to wildfire in a year. This is a long-term annual average and not intended to represent the actual number of housing units exposed in any specific year.Housing Unit Impact (HUImpact): HUImpact is a 30-m raster that represents the relative potential impact of fire to housing units at any pixel, if a fire were to occur. It is an index that incorporates the general consequences of fire on a home as a function of fire intensity and uses flame length probabilities from wildfire modeling to capture likely intensity of fire.Housing Unit Risk (HURisk): HURisk is a 30-m raster that integrates all four primary elements of wildfire risk - likelihood, intensity, susceptibility, and exposure - on pixels where housing unit density is greater than zero.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集描绘了针对美国人口密集区域的森林火灾风险组成部分。这些数据集展示了美国居民的居住分布以及现场火灾风险，即不利影响发生的地点的风险。由美国农业部森林服务局、落基山研究站和Pyrologix LLC生成的年度燃烧概率和火强度国家森林火灾危害数据集构成了社区森林火灾风险数据集的基础。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。年度燃烧概率通过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（米）单元格大小生成。为了将燃烧概率栅格数据下采样至更细的分辨率，以便于评估危害和社区风险，我们将数据上采样至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扩散到LANDFIRE燃料数据中代表的城市化区域，作为不可燃烧区域。燃烧概率栅格数据代表了截至2020年末的景观条件。通过执行涵盖火灾季节中发生的全部天气相关特性的综合FlamMap运行过程，并在基于这些天气类型发生可能性的各种结果中进行整合，以30米分辨率的精度对火强度特性进行建模。在火强度建模之前，LANDFIRE 2020数据已更新以反映2021年和2022年发生的燃料扰动。因此，火强度数据集代表了截至2022年末的景观条件。本出版物中代表居民居住位置的数据产品反映了2021年美国人口普查局对住宅单位和人口数量的估计，以及来自Onegeo和USA Structures的建筑物足迹数据，这两者均反映了2022年的情况。本出版物中包含的特定栅格数据集包括：建筑物数量：建筑物数量是表示每个30米像素内建筑物足迹数据集中建筑物数量的30米栅格。建筑物密度：建筑物密度是表示建筑物足迹数据集中建筑物密度的30米栅格（每平方公里建筑物数量 [km²]）。建筑物覆盖率：建筑物覆盖率是表示建筑物足迹覆盖的宜居土地面积的百分比的30米栅格。人口数量（PopCount）：PopCount是像素值代表每个像素内住宅人口数量的30米栅格。人口密度（PopDen）：PopDen是表示住宅人口密度的30米栅格（人/平方公里）。住宅单位数量（HUCount）：HUCount是表示每个像素内住宅单位数量的30米栅格。住宅单位密度（HUDen）：HUDen是表示住宅单位密度的30米栅格（住宅单位/平方公里）。住宅单位暴露度（HUExposure）：HUExposure是表示每个像素内预计每年可能暴露于森林火灾的住宅单位数量的30米栅格。这是一个长期年度平均值，并不旨在代表任何特定年份实际暴露的住宅单位数量。住宅单位影响（HUImpact）：HUImpact是表示任何像素内住宅单位相对于火灾潜在影响的30米栅格，如果发生火灾。这是一个综合指标，它将火灾对房屋的一般后果作为火灾强度和火焰长度概率的函数，并利用森林火灾建模捕获可能强度。住宅单位风险（HURisk）：HURisk是整合了四个主要森林火灾风险要素——可能性、强度、易损性和暴露性——的30米栅格，这些要素在住宅单位密度大于零的像素上。与数据集一起提供的方法论文档。有关下载数据及元数据信息，请参阅数据出版物的下载内容。请注意：由于网络服务的数据需求，该图像服务中的像素值已从原始栅格数据集中进行了调整。该服务主要面向数据可视化。相对值和空间模式在服务中得到了很大程度的保留，但用户应下载源数据以进行定量分析。本记录来自向https://data.gov目录馈入的美国农业部企业数据目录。本记录的数据包括以下资源：ISO-19139元数据、ArcGIS Hub数据集、ArcGIS GeoService。欲获取完整信息，请访问https://data.gov。