We developed the WULFFSS, a stochastic monthly gridded forest-fire model for the western United States (US). Operating at 12 km resolution, WULFFSS calculates monthly probabilities of fires that burn at least 100 ha of forest area as well as the forest area burned per fire.
Accurate prediction of forest fire spread is a critical management and scientific challenge as the world adapts to rapidly changing fire regimes. We reconstructed 5,400 daily burned area progression maps for 196 U.S. Northern Rocky Mountain wildfires (2012–2021) and used machine learning to estimate daily fire growth given local weather, hydroclimate, fuels and topography.
Rural communities are increasingly impacted by smoke produced by wildfires and forest management activties. Understanding local influences on smoke adaptation and mitigation is critical to social adaptation as fire risk continues to rise.
Background. Prescribed burning is a widely-used fire management strategy for maintaining socioeconomic and ecological resilience by mitigating the impacts of wildfires. Monitoring the effectiveness of prescribed burns on future fire spread, however, is challenged by limited data availability and quality.
We created the first annually resolved records of historical fire occurrence coupled with precise estimates of tree establishment for the northern half of the west slope of the Oregon Cascades, a region that is home to some of the most productive forests on earth.
Fire is strongly linked to outdoor recreation in the United States. Recreational uses of fires, whether in designated campgrounds or the backcountry, include warmth, cooking, and fostering a comfortable atmosphere. However, through inattention, negligence, or bad luck, recreational fires sometimes ignite wildfires. From 1992 through 2020, such ignitions accounted for an estimated 12% of human-caused wildfires and 8% of the area burned by those wildfires in Washington, Oregon, and California. 76% of the recreation-caused ignitions occurred on public lands: 50% on lands managed by the U.S. Forest Service, 15% on other federal lands, and 11% on state, county, or local lands.
With the aim of informing strategies to limit the risk of recreation-caused ignitions, we evaluated whether the density of wildfires ignited by recreation or ceremony on U.S. Forest Service lands, and the size of such wildfires, is influenced by proximity to designated campgrounds, visitor density, previous and current drought conditions, and the type of vegetation surrounding the ignition point. With respect to recreation-caused ignitions, we tested the common assumption that large wildfires tend to be enabled by wet conditions in the prior growing season where vegetation is not continuous, and by dry conditions in the current growing season where vegetation is abundant and the climate generally limits flammability. We accounted for the potential effects of ecoregion on these associations given that vegetation composition, climate, and historical fire-return intervals and sizes vary among ecoregions.
Post-wildfire debris flows (PFDFs) frequently threaten life, property and infrastructure in California. To date, there is no comprehensive assessment of their spatial distribution, seasonality, atmospheric drivers and interannual variability across the state.