20230615 18150200 1.0 TRUE 150000000 5000 ItemDescription The purpose of the Pacific Northwest Wildfire Hazard Assessment (PNRA) is to provide foundational information about wildfire hazard across the Pacific Northwest Region (which encompasses the states of Oregon and Washington). Such information supports both wildfire and vegetation management planning and provides a defensible, robust suite of analytics that are used by numerous partners across Oregon and Washington. The PNRA modeling provides spatially resolved information about wildfire likelihood and intensity across the Region. Modified results of this hazard assessment were used to update the previously completed Quantitative Wildfire Risk Assessment (QWRA). A QWRA considers several different components, each resolved spatially across the region, including: • likelihood of a fire burning, • the intensity of a fire if one should occur, • the exposure of assets and resources based on their locations, and • the susceptibility of those assets and resources <DIV STYLE="text-align:Left;"><DIV><DIV>WildEST – Wildfire Exposure Simulation ToolWildEST is a scripted geospatial process used for simulating potential fire behavior characteristics that addresses two shortcomings of current methods. WildEST performs multiple deterministic simulations under a range of weather types (wind speed, wind direction, fuel moisture content). Rather than weighting results solely according to the temporal relative frequencies of the weather scenarios, the WildEST process integrates results by weighting them according to their weather type probabilities (WTP), which appropriately weights high-spread conditions into the calculations.Most WildEST results apply to the head of the fire. For fire-effects calculations, WildEST also generates flame-length probability rasters that incorporate non-heading spread directions, for which fire intensity is considerably lower than at the head of the fire. These “NVC” FLPs are analogous to FLP rasters produced by FSim. These WildEST results were completed on the 2022 current-condition fuelscape (derived from LANDFIRE), which reflects fuelscape conditions for the year 2022 and includes all historical fuel disturbances through 2021. WildEST results were modified for risk calculations in the QWRA using an irrigated agriculture mask to assign FLPs to pixels which are likely to be irrigated during fire season. An irrigated agriculture mask was created from LANDFIRE 2.2.0 Fire Behavior Fuel Models (where the model = “NB3”), and data collected from IrrMapper (Ketchum et al., 2020). All NB3 pixels as well as pixels that were classified as irrigated in three of the most recent five years in IrrMapper were included in the irrigated agriculture mask. Pixels in the irrigated agriculture mask were assigned an FLP of 0.75 for flame lengths between 0 – 2 feet, 0.25 for flame lengths 2 – 4 feet, and an FLP of 0 for all intensity values greater than 4 feet. This fire-effects flame-length probability (FLP) dataset represents the probability of 2 - 4 feet flame lengths for a given pixel in the fuelscape, incorporating both heading and non-heading spread directions. Fire-effects flame-length probability rasters are used for effects analysis in a landscape wildfire risk assessment, as described in USFS GTR-315. Probability is calculated using non-heading fire behavior and is weighted according to WTP, incorporating both temporal frequencies and the influence of high-spread conditions. Raster resolution is 30m. Data finalized 11/17/2022.Ketchum, D., Jencso, K., Maneta, M.P., Melton, F., Jones, M.O., Huntington, J., 2020. IrrMapper: A Machine Learning Approach for High Resolution Mapping of Irrigated Agriculture Across the Western U.S. Remote Sensing 12, 2328. <A href="https://doi.org/10.3390/rs12142328" STYLE="text-decoration:underline;">https://doi.org/10.3390/rs12142328</A></DIV></DIV></DIV> Primary data contact: Ian Rickert (Regional Fire Management Planning Specialist) ian.rickert@usda.gov This dataset was developed for The USFS Pacific Northwest Region (R6) by Pyrologix LLC (www.pyrologix.com), and modified for use in the QWRA by Oregon State University, College of Forestry (andy.mcevoy@oregonstate.edu). Fire Intensity Level 2 QWRA Region 6 PNW HVRA <DIV STYLE="text-align:Left;">The user must be aware of data conditions and must ultimately bear responsibility for the appropriate use of the information with respect to possible errors, possible omissions, map scale, data collection methodology, data currency, and other conditions specific to certain data.</DIV> 20230629