Here, we synthesized literature and conducted a survey of forest and fire managers to assess current understanding of how fire interacts with aspen stands, as well as to examine possible factors that influence fire occurrence, behavior, and severity in aspen communities. We found evidence that the presence of aspen reduces fire occurrence, fire behavior, and fire severity, but this effect is dependent on many factors, including the percentage of aspen vs conifers in the overstory, load and type of understory fuels, weather, and season. We did not find any quantitative management guidelines on how to create, maintain, or use aspen stands to reduce fire risk. The large gap between “common knowledge” and empirical evidence regarding aspen’s ability to inhibit fire requires further research.
The third webinar of the Forest Service’s Research and Development SCIENCEx FIRE week.
Wildland Fire Behavior and Ignition | Sara McAllister
3D Time-Dependent Fire Behavior Models: What They Do and the Need for Observational Datasets | Ruddy Mell
Fire Behavior Assessment Team (FBAT) and Wildfire Monitoring | Matt Dickinson
Better wildland fire governance is needed to protect biodiversity, foster carbon sequestration and healthy forests and assure they are providing goods and services that do not vanish in wildfire smoke.
As Chairman and on behalf of the Organizing Committee of the 8th International Wildland Fire Conference we invite you to come to Portugal with your knowledge, insights, and thoughts. We welcome you to contribute with your institutional or professional case study, your scientific work or your operational success or failure in tackling complexity and uncertainty when governing or managing wildfire risk.
At Porto, you will have a lifetime influencing professional experience, through the opportunity to meet with thousands of people coming from all over the world. We all share similar problems and are deeply committed to work on the solutions.
We will be honored to host you at Porto, to discuss and participate in defining Governance principles towards the development an international framework. We believe that your piece of the puzzle will matter to help your nation and all nations to be better prepared to deal with the challenges ahead of us and to build fire-resilient landscape and societies.
TIAGO MARTINS DE OLIVEIRA
Chairman of the AGIF Board of Directors
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On a dry winter morning between Christmas and New Year’s Eve 2021, the communities in Boulder County braced for the wind. The area lies at the base of the Front Range, made up of flat-topped mesas and open grasslands where creek bottoms are lined with cottonwood trees. On the outskirts of the communities are scattered homes and ranchettes. Farther east are established neighborhoods with mature landscaping and newer subdivisions sparsely planted with shrubs and ornamental hardwoods. Green corridors and trails run through the area.
This presentation discusses the results of 17 years of active fire data from Moderate Resolution Imaging Spectroradiometer (MODIS) to characterize the daytime and nighttime dynamics of wildfires across the continental US. Whereas daytime fire activity was widely detected regardless of fire type, nighttime fire activity was mainly detected inside wildfires and particularly within large wildfires in the western US. The analysis also found that as fuels dry, there is an increase in larger and more intense wildfires with higher chances that fire activity will persist overnight. Results indicate that increasing trends in nighttime wildfire activity have coincided with increasing wildfire sizes. Nighttime fire activity already poses additional risks to firefighters and communities, and this presentation discussed the probability that projected increases in the frequency of large wildfires will be accompanied by increases in the extent and intensity of nighttime fire activity.
Modeling fire spread in sagebrush steppe using FARSITE: Improving input data and simulation accuracy
Using RAP to inform pre-fire FBFM selection increased the accuracy of FARSITE simulations compared to parameterization with the standard LANDFIRE FBFM maps, in sagebrush steppe. Additionally, the crosswalk method appeared to have regional generalizability. Flanking and backfires were the primary source of disagreements between simulated and observed fire spread in FARSITE, which are sources of error that may require modeling of lateral heterogeneity in fuels and fire processes at finer scales than used here.
Historical wildfire ignition locations and NOAA’s hourly time series of surface weather at 2.5 km resolution are used to drive ELMFIRE to produce wildfire hazards representative of the 2022 and 2052 conditions at 30 m resolution, with the future weather conditions scaled to the IPCC CMIP5 RCP4.5 model ensemble predictions. Winds and vegetation were held constant between the 2022 and 2052 simulations, and climate change’s impacts on the future fuel conditions are the main contributors to the changes observed in the 2052 results. Non-zero wildfire exposure is estimated for 71.8 million out of 140 million properties across CONUS. Climate change impacts add another 11% properties to this non-zero exposure class over the next 30 years, with much of this change observed in the forested areas east of the Mississippi River. “Major” aggregate wildfire exposure of greater than 6% over the 30-year analysis period from 2022 to 2052 is estimated for 10.2 million properties. The FSF-WFM represents a notable contribution to the ability to produce property-specific, climate-adjusted wildfire risk assessments in the US.
2020 was a record year for wildfires in recent history, though the area burned was close to estimates of pre-suppression burning. We should expect more of these types of fire seasons in the future. Much of the burning was destructive rather than restorative and impacts to humans were severe.
Evidence for lack of a fuel effect on forest and shrubland fire rates of spread under elevated fire danger conditions: Implications for modelling and management
This review and analysis of the relevant scientific literature on the subject suggest that fuel characteristics have a gradual diminishing effect on the rate of fire spread in forest and shrubland fuel types with increasing fire danger, with the effect not being observable under extreme fire danger conditions. Empirical-based fire spread models with multiplicative fuel functions generally do not capture this effect adequately. The implications of this outcome on fire spread modelling and fuels management are discussed.
Climate-driven changes in global temperatures and aridity are directly correlated with the decreasing interval between high-elevation fires. Fire activity is increasingly disproportionate at higher elevations than that of lower elevation forests in the Western United States. Studies documented an upslope advance of high-elevation fires of roughly 7.6 m (25 ft) per year. An additional 81,500 km2 (31,500 miles2) of the western United States forested regions were exposed to fires due to increased aridity between 1984 and 2017.