Wildfire Risk Extreme USA

The potential for wildfire exposure is a growing hazard as temperatures rise, wildland fuels accumulate, and people continue to build structures in areas of elevated wildfire risk. Wildfire Risk Extreme provides an up-to-date, scientific model that accurately captures wildfire risk under severe conditions, for every location in the United States. This sample data set is limited to the Marin County, CA area.

Wildfire Risk Extreme was designed as a companion product to Precisely's existing Wildfire Risk. Wildfire Risk Extreme includes temperature, relative humidity, and maximum wind speeds under fire conditions that occur only 1 percent of the time. Additionally, the direction of predominant winds in an area provides insight provides insight into where communities may be vulnerable. Also, for the first time, the threat from urban conflagration (fires that are no longer carried by wildland fuel but by the ignition of structures by other structures) is modeled. This new product offers a nationwide wildfire hazard and risk assessment tool that incorporates the predicted severity (hazard) and predicted frequency (risk) or wildfire at a given location.

Many wildfire-related datasets are delivered in a format that divides the landscape into square grids. A square has very little relation to how a fire burns and the variation from square to square can be difficult to interpret. Wildfire Risk Extreme takes a different approach: All the datasets Wildfire Risk Extreme uses to create a final analysis – many of which come in a grid format – are integrated into polygons that reflect the landscape and how wildfires would actually burn within that landscape. Wildfire Risk Extreme divides the data into firesheds that are based on the topography (hills and valleys) of the landscape. These firesheds correlate to vegetation or wildland fuels and determine how a fire might burn and behave. This means that firesheds are more likely to divide geography into landscape-based units that exhibit similarities in vegetation, slope, and resultant fire behavior. The [Wildland](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/IWx8BZabTu5rZylF7Ss00A) and [Intermix](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/Kmal0pyr4ggiuOfeqF7ALw) modules in Wildfire Risk Extreme use the concept of firesheds to aggregate the landscape.

Wildfire Risk Extreme also accounts for the fact that firesheds are impacted by wildfire effects from outside of their boundaries. A fireshed may be mostly covered by a meadow but surrounded by volatile timber or chaparral (a California reference). If a structure exists in the meadow, it is not only subject from the grass fuel in the fireshed, but also to fire embers in the surrounding firesheds' vegetation. To account for this, Wildfire Risk Extreme incorporates adjacent fireshed values into the threat profile for every fireshed, providing a more realistic definition of the fire environment.

Wildfire Risk Extreme uses the concept of dividing the landscape into relative amounts of built environment (structures, roads, and other infrastructure) versus pure wildland fuels. The rationale for this distinction is that wildland fires behave differently when burning in pure wildland areas than when burning through fuel that is interrupted by structures and roads. Similarly, suppression of wildland fires is conducted differently – and with varying degrees of success – in remote areas compared to densely populated areas. Wildfire Risk Extreme captures these differences by categorizing the landscape into four separate wildfire risk types, each of which modeled with its own set of inputs and methodology:

- [Wildland](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/IWx8BZabTu5rZylF7Ss00A)
- [Intermix](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/Kmal0pyr4ggiuOfeqF7ALw)
- [Interface](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/2Av~UbjeAuleD4pb2DxOMA)
- [Ember/Flame Impingement Zone](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/NXvJvBCGiYLQfQzb9tZ_xA)

This is a subset of the full product’s geographic extent. The full commercial offering features geographic coverage of the entire United States. If you are interested in licensing the full product, please contact Precisely at: [e-mail]

随着气温攀升、林地燃料持续累积，且人类持续在野火风险偏高区域兴建建构筑物，野火暴露风险已演变为日益严峻的灾害隐患。野火风险极境（Wildfire Risk Extreme）提供了一套与时俱进的科学模型，可精准捕捉美国全境任意区域极端条件下的野火风险。本次示例数据集仅限加利福尼亚州马林县（Marin County, CA）范围。

Wildfire Risk Extreme 是作为 Precisely 公司现有野火风险产品的配套工具开发而成。该产品涵盖仅在1%概率下才会发生的火灾场景下的气温、相对湿度与最大风速数据。此外，区域主导风向可为社区潜在脆弱区域的研判提供关键参考。本次产品还首次实现了对城市跨建筑火灾蔓延风险的建模——此类火灾不再依托林地燃料传播，而是通过相邻建构筑物间的相互引燃持续扩散。这款全新产品可提供覆盖全美范围的野火灾害与风险评估工具，整合了特定位置野火的预测烈度（灾害等级）与预测发生频率（风险水平）。

当前多数野火相关数据集采用将地表划分为方形网格的格式进行交付，但方形网格与野火实际燃烧路径的关联性极弱，且网格间的风险差异也难以直观解读。Wildfire Risk Extreme 采用了截然不同的建模思路：其用于生成最终分析结果的全部数据集（其中多数本为网格格式）均被整合为贴合地表形态、并能反映野火在该区域实际燃烧行为的多边形单元。该产品基于地表地形（山丘与山谷）将数据划分为火灾流域（firesheds），这些火灾流域与植被类型或林地燃料分布相匹配，可用于推演野火的燃烧路径与行为特征。换言之，火灾流域更倾向于按照植被、坡度及野火行为特征的相似性进行地理分区。Wildfire Risk Extreme 内置的[Wildland](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/IWx8BZabTu5rZylF7Ss00A)与[Intermix](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/Kmal0pyr4ggiuOfeqF7ALw)模块，即通过火灾流域概念实现地表区域聚合。

Wildfire Risk Extreme 同时考虑了火灾流域边界外的野火影响对其造成的冲击。某一火灾流域可能主体为草甸，但周边环绕着易燃林木或加州典型灌丛。若该草甸内存在建构筑物，其面临的野火风险不仅来自本流域内的草地燃料，还包括周边火灾流域植被产生的火烬。为还原真实的火灾环境，该产品将相邻火灾流域的风险值纳入每个流域的威胁评估体系，从而更精准地刻画区域火灾环境。

Wildfire Risk Extreme 还引入了将地表划分为建成环境（建构筑物、道路与其他基础设施）与纯林地燃料相对占比的分类思路。其核心理由在于，野火在纯林地区域的燃烧行为与在被建构筑物、道路阻断的燃料区域的燃烧行为存在显著差异。同理，偏远区域与人口密集区域的野火扑救策略与成效也各不相同。该产品通过将地表划分为四类野火风险类型，并分别采用专属的输入参数与建模方法实现风险评估：
- [Wildland](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/IWx8BZabTu5rZylF7Ss00A)
- [Intermix](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/Kmal0pyr4ggiuOfeqF7ALw)
- [Interface](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/2Av~UbjeAuleD4pb2DxOMA)
- [Ember/Flame Impingement Zone](https://help.precisely.com/r/OhmEbpQTUxYR9oe0m9v7vA/NXvJvBCGiYLQfQzb9tZ_xA)

本次提供的数据集为完整产品地理覆盖范围的子集。该商业完整版可覆盖美国全境。若您有意获取完整产品授权，请联系 Precisely 官方邮箱：[e-mail]

搜集汇总

背景与挑战

背景概述

Wildfire Risk Extreme USA是一个美国野火极端风险评估数据集，采用基于地形和植被的'fireshed'多边形方法（而非传统网格）来模拟真实火势行为，并整合极端气象条件和城市大火威胁模型。该数据集将景观分为四种风险类型，以提供更精准的全国性野火危害和风险分析，示例数据限于加州马林县区域。