Summary: Wildfires are becoming more destructive as burned area increases and as more homes are built in the wildland-urban interface, but it is unclear how these patterns are affected by changing wildfire behavior in different fuel types. To better understand changing patterns of wildfire destruction, we mapped buildings exposed to and destroyed by wildfires in the conterminous U.S. from 2000-2020. From these maps, we determined that the probability of an exposed building being destroyed by wildfire has more than tripled over the past two decades, and that more wildfire destruction is occurring in forests relative to grass and shrublands. Understanding these changing patterns can help us design more effective strategies to mitigate risk.
Title: Fire and Water: What determines water-quality response after wildfire?
Speaker: Sheila Murphy, Research Hydrologist, USGS Water Resources Mission Area
Summary: Wildfires can increase the risk of flooding, erosion, and degraded water quality, which can damage infrastructure, increase treatment costs for drinking water providers, and impair stream ecosystems. However, the reported nature and extent of water-quality effects after wildfire have varied widely, from massive increases in the amount of sediment, nutrients, and metals delivered to downstream waters to no noticeable change. Given the wide range of potential post-wildfire effects on water supplies, water providers and land managers need accurate guidance on what to expect in their watersheds to enable plans for minimizing impacts on water supplies. This presentation will describe selected USGS work linking post-wildfire water-quality response to climate, land cover, geology, catchment hydrology, and other factors. Given the predicted ongoing risk of wildfire to water supplies, it is imperative to develop capacity to predict, monitor, and mitigate wildfire effects on our water resources.
Date: June 26, 2024, at 2-3 pm Eastern Time
Title: Fire, flood, and mud: Assessing postfire debris-flow hazards across the western U.S.
Speaker: Jason Kean, Research Hydrologist, Landslide Hazards Program
Summary: The western U.S. has a history of damaging debris flows after wildfire, and it is facing expanded postfire risk due to increased wildfire activity and development in susceptible areas. After a wildfire, emergency managers need rapid answers to the questions: Where in the burn area are debris flows likely? How much rain will it take to trigger a debris flow? And how big will that debris flow be? Using examples of recent postfire events, we describe how the USGS and research partners have worked to improve the answers to those questions over the last twenty-five years. We also describe current work to improve debris-flow hazard assessments with new tools to answer the questions: Where will debris flows travel? How long it will take the burn area to recover? And what are the risks from future fires?
Date: Tuesday, October 10 at 3 pm ET
Title: Multi-fidelity Coupled Fire/Atmosphere Modeling to Support Proactive Approaches to Wildland Fire
Speaker: Dr. Rod Linn, Team Leader, Atmospheric Modeling and Weapons Phenomenology, Los Alamos National Laboratory
Summary: As the fire community looks towards proactive approaches to manage the growing challenges of wildland fire, the importance of science-based decision support is increasing. In wildland fire and land management, the decision space is different when determining proactive management strategies compared with reactive crisis management, just as they are in any field. There is an expectation that decision makers have weighed the pros and cons of their action (or lack of action) and are optimizing their actions to meet objectives, reducing costs (not just monetary costs), and avoiding unintended consequences. Whether it is assessing possible benefits of fuels treatments or planning and analyzing prescribed fires, next generation coupled fire atmosphere models can contribute to the science basis for land management decisions. The requirements on these models are that they capture the influences of the heterogenous fire environment on fire behavior with sufficient detail to enable decision makers to understand the consequences of the various possible decisions. Continual improvement of the science basis and availability of decision support requires a multi-fidelity modeling approach where detailed models can continuously help us increase our understanding of the relationship between fire behavior and its environment in current or future climate scenarios, and faster running tools can encompass this understanding in an accessible tool.
Summary: Wildfire burned area is increasing, creating challenges for federal agencies to reduce the negative impacts of wildfires on society while balancing their benefits to ecosystems. The Bipartisan Infrastructure Law (BIL) provided funding to help address this challenge but directed agencies to prioritize mitigation actions on lands with very high wildfire hazard potential. To help meet monitoring, maintenance, and treatment plan requirements under the BIL, the USGS inventoried existing wildfire hazard and risk assessments and created an interactive web application, or clearinghouse, to navigate the inventory. The inventory and clearinghouse document the variation among assessments and that no assessment perfectly represents all lands or values at risk. They also provide baseline information to evaluate and identify existing hazard and risk assessment gaps. This presentation highlights the inventory and clearinghouse, reviews the existing wildfire hazard and risk assessments, identifies gaps in the assessments, and opportunities to fill those gaps.
Title: The Wildland Fire Trends Tool: A web-based data visualization tool for displaying wildfire trends and patterns in the western United States
Speakers:
Douglas J. Shinneman, Research Ecologist, USGS Forest and Rangeland Ecosystem Science Center
Michelle I Jeffries, Ecologist, USGS Forest and Rangeland Ecosystem Science Center
Description: Accurately assessing recent and historical wildfire activity is critical for numerous agencies who manage fire-prone landscapes. The Wildland Fire Trends Tool (WFTT) is a data visualization and analysis tool that calculates and displays wildfire trends and patterns for the western U.S. based on user-selected regions of interest, time periods, and ecosystem types. For instance, users can determine whether the area burned by wildfire is increasing or decreasing over time for a specific ecoregion or for land ownership types of interest. The tool is available via a web application and generates a variety of maps, graphs, and tabular data that provide useful information for fire science and management objectives, as well as for the interested public.