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Wildfires are an essential part of a healthy ecosystem, yet the expansion of the wildland-urban interface, combined with climatic changes and other anthropogenic activities, have led to the rise of wildfire hazards in the past few decades. Managing future wildfires and their multi-dimensional impacts requires moving from traditional reactive response to deploying proactive policies, strategies, and interventional programs to reduce wildfire risk to wildland-urban interface communities. Existing risk assessment frameworks lack a unified analytical method that properly captures uncertainties and the impact of decisions across social, ecological, and technical systems, hindering effective decision-making related to risk reduction investments. In this paper, a conceptual probabilistic wildfire risk assessment framework that propagates modeling uncertainties is presented. The framework characterizes the dynamic risk through spatial probability density functions of loss, where loss can include different decision variables, such as physical, social, economic, environmental, and health impacts, depending on the stakeholder needs and jurisdiction. The proposed approach consists of a computational framework to propagate and integrate uncertainties in the fire scenarios, propagation of fire in the wildland and urban areas, damage, and loss analyses. Elements of this framework that require further research are identified, and the complexity in characterizing wildfire losses and the need for an analytical-deliberative process to include the perspectives of the spectrum of stakeholders are discussed.
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This content will become publicly available on January 12, 2027
Cluster-Based Active-Learning Scenario Reduction Framework for Probabilistic Wildfire Risk Assessment
Wildfires pose an escalating risk to communities and infrastructure, especially in regions undergoing increased fuel dryness and temperature extremes driven by climate change, as well as continued expansion into the wildland-urban interface (WUI). Probabilistic wildfire risk assessment provides a rigorous means of quantifying potential impacts, but its application is often hindered by the high computational cost of working with hundreds of thousands of complex wildfire scenarios. This study introduces a novel scenario reduction framework tailored to the unique characteristics of wildfire hazards, which often lack standard intensity metrics and exhibit highly nonlinear, spatially distributed behavior. The proposed framework selects a subset of scenarios that best represent the spatial and statistical diversity of the full dataset, thereby greatly reducing computational costs while accounting for uncertainties. This is achieved by mapping complex wildfire scenarios into a high-dimensional feature space, enabling similarity assessments based on spatial consequence patterns rather than standard intensity metrics. A k-medoids clustering approach is then used to identify a representative subset of scenarios, while an active-learning-based outlier selection procedure incorporates rare but high-impact events without inflating computational demands. The framework was first demonstrated using a simple illustrative example to show how its performance responds to different data characteristics. To further demonstrate the practicality of the framework, it was used for wildfire risk assessment in Spokane County, Washington, where the full dataset (1000 scenarios) was reduced to 41 representative scenarios while preserving the spatial patterns of burn probability and building damage with high fidelity. The results demonstrated that the framework significantly improves computational efficiency and accuracy compared to traditional scenario reduction methods, offering a scalable and flexible tool for probabilistic wildfire risk assessment.
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- Award ID(s):
- 2438985
- PAR ID:
- 10659052
- Publisher / Repository:
- ASCE (American Society of Civil Engineers)
- Date Published:
- Journal Name:
- ASCE-ASME Journal of Risk and Uncertainty in Engineering Systems, Part A: Civil Engineering
- ISSN:
- 2376-7642
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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