Surface Fire Research Articles

Woody charcoal with traces of pre-charring decay from the Late Oligocene (Chattian) of Norken (Westerwald, Rhineland-Palatinate, W Germany)

A variety of traces of pre-charring decay are described from coniferous charcoals from the Norken locality, stratigraphically positioned within the Breitscheid Formation (Late Oligocene, Chattian) of the Westerwald area (Rhineland-Palatinate; W Germany). The traces include three-dimensionally preserved as well as collapsed fungal hyphae, collapsed filamentous structures (maybe related to ascomycetes), so-called shot-like holes of different diameters in cell walls of tracheids, as well as crater-like structures on the surface of tracheid walls. The latter occur on tracheids with bordered pits, in the direct vicinity of charred phloem (so far only rarely reported from pre-Quaternary charcoal). These observations, together with evidence that some of the charcoal fragments originated from wood that dried out prior to charring, point to a surface fire as the most likely source of the charcoal, although it cannot totally be ruled out that (partly) dead but still standing trees were affected during a crown fire. The data from the Late Oligocene of Norken provide further evidence that pre-Quaternary charcoal can be used as an additional, so far largely underutilized source for additional information about plant– microorganism interactions in deep time.

Physics-Based Simulations of Flow and Fire Development Downstream of a Canopy

The behavior of a grassland fire propagating downstream of a forest canopy has been simulated numerically using the fully physics-based wildfire model FIRESTAR3D. This configuration reproduces quite accurately the situation encountered when a wildfire spreads from a forest to an open grassland, as can be the case in a fuel break or a clearing, or during a prescribed burning operation. One of the objectives of this study was to evaluate the impact of the presence of a canopy upstream of a grassfire, especially the modifications of the local wind conditions before and inside a clearing or a fuel break. The knowledge of this kind of information constitutes a major element in improving the safety conditions of forest managers and firefighters in charge of firefighting or prescribed burning operations in such configurations. Another objective was to study the behavior of the fire under realistic turbulent flow conditions, i.e., flow resulting from the interaction between an atmospheric boundary layer (ABL) with a surrounding canopy. Therefore, the study was divided into two phases. The first phase consisted of generating an ABL/canopy turbulent flow above a pine forest (10 m high, 200 m long) using periodic boundary conditions along the streamwise direction. Large Eddy Simulations (LES) were carried out for a sufficiently long time to achieve a quasi-fully developed turbulence. The second phase consisted of simulating the propagation of a surface fire through a grassland, bordered upstream by a forest section (having the same characteristics used for the first step), while imposing the turbulent flow obtained from the first step as a dynamic inlet condition to the domain. The simulations were carried out for a wind speed that ranged between 1 and 12 m/s; these values have allowed the simulations to cover the two regimes of propagation of surfaces fires, namely plume-dominated and wind-driven fires.

New Approach Evaluating Peatland Fires in Indonesian Factors

Until 2018, the El Niño–Southern Oscillation (ENSO) was used as an explanation for fires in Indonesia’s peatlands. However, when the 2019 fires occurred independently of El Niño, more suitable indicators and methods were required to (a) analyze, (b) evaluate and (c) forecast peatland fires. In this study, we introduced the OLR–MC index—one of the rain-related indices derived from OLR (outgoing longwave radiation) in MC (maritime continent) area in Indonesia. This index showed stronger correlation with active peatland fires than the conventional ENSO index, and is likely to be able to respond to heat and dry weather supposed to be under climate-change conditions. We then analyzed peatland fires in the top six fire years from 2002 to 2018 and showed that peatland fires occurred in three stages—surface fire, shallow peatland fire and deep peatland fire. To explain each stage, we proposed a one-dimensional groundwater level (GWL) prediction model (named as MODEL-0). MODEL-0 predicts GWL from daily rainfall. Analysis using MODEL-0 showed the GWL thresholds for the three fire stages were between -300 mm and -500 mm; peatland fire activities during the three fire stages were dependent on these GWL values. The validity of MODEL-0 was shown by comparison with the measured values of GWL in the top three fire years.

Role of Horizontal Eddy Diffusivity within the Canopy on Fire Spread

Wind profile observations are used to estimate turbulent mixing in the atmospheric boundary layer from 1 m up to 300 m height in two locations of pine forests characteristic of the southeast US region, and to 30 m height at one location in the northeast. Basic turbulence characteristics of the boundary layers above and within the canopy were measured near prescribed fires for time periods spanning the burns. Together with theoretical models for the mean horizontal velocity and empirical relations between mean flow and variance, we derive the lateral diffusivity using Taylor’s frozen turbulence hypothesis in the thin surface-fuel layer. This parameter is used in a simple 1D model to predict the spread of surface fires in different wind conditions. Initial assessments of sensitivity of the fire spread rates to the lateral diffusivity are made. The lateral diffusivity with and without fire-induced wind is estimated and associated fire spread rates are explored. Our results support the conceptual framework that eddy dynamics in the fuel layer is set by larger eddies developed in the canopy layer aloft. The presence of fire modifies the wind, hence spread rate, depending on the fire intensity.

Пожежостійкість і постпірогенний відпад соснових лісів лівобережної частини Харківської області за різних рівнів пожежної небезпеки за умовами погоди

Пожежі є одними з найнебезпечніших чинників дестабілізації лісів. Визначення особливостей постпірогенного розвитку сосняків дає змогу пом’якшити негативні наслідки, спричинені лісовими пожежами, та допомогти в прийнятті рішень стосовно ведення господарства в таких лісах. Виявлено, що санітарний стан насаджень залежав від значення комплексного показника пожежної небезпеки (КППН) на момент пожежі та погіршувався у міру його збільшення (r = 0,71; p = 0,05). За вищих значень КППН підвищуються інтенсивність тепловиділення під час пожежі та ступінь вигорання лісової підстилки. Встановлено, що за КППН від 1 500 до 3 000 балів індекс санітарного стану насаджень варіює від II,0 до III,9; частка відпаду сягає 20 %. За подальшого збільшення значень КППН понад 5 000 балів індекс стану насадження через рік після пожежі становить III,5–V,0. З’ясовано, що висота полум’я та висота нагару на стовбурах достовірно не залежать від рівня пожежної небезпеки за умовами погоди. Вдосконалено підходи до прогнозування постпірогенного відпаду на рівні насадження з урахуванням характеристик пожежонебезпечного сезону, ступеня пошкодження дерев у насадженні та його таксаційних характеристик.

Effects of human-related and biotic landscape features on the occurrence and size of modern forest fires in Sweden

The influence of landscape features on the occurrence and size of forest fires in Northern Europe has not been well-studied. In this paper, we analyzed the impact of human-related landscape properties (road and human population density), biotic features (amount of firebreak area and vegetation zone) and fire weather indices (Buildup Index, BUI and Initial Spread Index, ISI) on the occurrence and size of forest fires in Sweden from 1998 to 2017. To analyze the environmental controls of fire occurrence and fire size under different levels of climatological fire hazard, we divided the data into two subsets: (1) large fire years (LFY), defined as the years with the total amount of burned area being higher than the dataset-wide average (2002, 2003, 2006, 2008 and 2014), and (2) the remaining years (nLFY). Our analytical approach was based on spatial models using Integrated Nested Laplace Approximations (INLA). Models built on both LFY and nLFY subsets suggested a strong human influence on fire occurrence: road density, the number of firebreaks, and population density, all were positively associated with fire occurrence, suggesting an important role of human-related ignitions. The southernmost vegetation zones in Sweden (boreo-nemoral and nemoral) exhibited the highest fire occurrence (LFY), a pattern potentially related to a higher population density in combination with weather more conducive for fires in this part of the country. The patterns that emerged from the fire size models pointed to the climate as the main factor controlling fire size, irrespective of the type of years analyzed. Road density, number of firebreaks and population density showed a negative association with fire size, possibly indicating higher efficiency of fire suppression in the areas with higher human presence. Vegetation zones were selected as an informative predictor, indicating that the fire activity varies across the zones, with those in mid-Sweden being the most prone to large events. The ISI correlated strongly and positively with fire size in both subsets (LFY and nLFY), pointing to the role of weather conditions favorable for fire spread, primarily that of surface fires. The BUI showed a weak negative correlation to fire size, indicating that dryness of organic horizon, specifically its deeper layers, is less relevant for predicting fire size. Contemporary fire activity in Sweden is driven by a combination of human-related ignitions, and weather conditions controlling fire spread with a moderate effect of vegetation composition and generally efficient fire suppression. Human-related landscape features (roads and population density) play a major role in shaping ignition patterns, whereas climate (ISI) and vegetation properties appear informative as predictors of fire size, even under a modern fire suppression effort.

Organic fragments newly released from heat-treated peat soils create synergies with dissolved organic carbon to enhance Cr(VI) removal.

Surface fires occur naturally or anthropogenically and can raise the temperature at the soil surface up to 600°C. The heat derived from the surface fire can be subsequently transferred into CO2-enriched subsoils. As a result, the chemical compositions of soil organic matter (SOM) may be altered in fire-impacted anaerobic environments, indirectly influencing the redox transformations of pollutants, such as Cr(VI). In this study, a peat soil was heated up to 600°C with limited air flow to simulate the effects of heat on the SOM during surface fire events. Then, Cr(VI) removal, including reduction and sorption, by the heat-treated peat soils was determined in relation to changes in the soil organic components. The results showed that the amount of O-containing functional groups, -CH2/-CH3 units of aliphatic groups, and dissolved organic carbon (DOC) in the SOM gradually decreased with an increase in the heating temperature. The removal of 0.1932mM Cr(VI) did not exhibit a consistent decline along with the changes in these soil components. The heating temperatures of 200 and 250°C were the thresholds that led to the decomposition of temperature-sensitive soil organic components such as lignin and other labile SOM. Such newly released organic fragments synergized lignin-like substances and carboxyl groups, resulting in up to 99% removal of the initially added Cr(VI). As the heating temperatures were increased from 300 to 600°C, Cr(VI) reduction decreased from 66% to 20%. The black carbon-like materials and/or aromatic-containing moieties were the major components responsible for Cr(VI) reduction in 600°C-treated peat soils.

Pine Species That Support Crown Fire Regimes Have Lower Leaf-Level Terpene Contents Than Those Native to Surface Fire Regimes

Fire is increasingly being recognised as an important evolutionary driver in fire-prone environments. Biochemical traits such as terpene (volatile isoprenoid) concentration are assumed to influence plant flammability but have often been overlooked as fire adaptations. We have measured the leaf-level flammability and terpene content of a selection of Pinus species native to environments with differing fire regimes (crown fire, surface fire and no fire). We demonstrate that this biochemical trait is associated with leaf-level flammability which likely links to fire-proneness and we suggest that this contributes to post-fire seedling survival. We find that surface-fire species have the highest terpene abundance and are intrinsically the most flammable, compared to crown-fire species. We suggest that the biochemical traits of surface fire species may have been under selective pressure to modify the fire environment at the leaf and litter scale to moderate fire spread and intensity. We indicate that litter flammability is driven not only by packing ratios and bulk density, but also by terpene content.

Fuel characteristics and fire behavior in mixed deciduous forest areas with different fire frequencies in Doi Suthep-Pui National Park, Northern Thailand

Fires are commonly used as part of the livelihood of local people in Thailand. However, population growth is causing serious problems with agricultural expansion, forest encroachment, and illegal settlement in protected areas. Human activities are causing fires in deciduous forests increasingly frequently. Understanding the fuel characteristics and fire behavior in mixed deciduous forest areas with different fire frequencies in Doi Suthep-Pui National Park will help in developing a suitable fire management plan for this area. Twenty quadrats, each 1 × 1 m, were used to collect data regarding fuel characteristics, and 50 × 50 m quadrats were used to study fire behavior in low and high fire-frequency areas. The fuel-load data were collected every month for a period of 1 year. The results indicated that in the two fire-frequency areas, the main fuel component in this forest type was litter (leaves). Fire consumed approximately 60–70% of the total fuel loads, and fuel recovery to the original level was predicted to take around 2 years. All the fire behavior features in the LFA and the HFA showed similar characteristics, and the fire type in both areas was defined as surface fire with low intensity, which usually occurs in deciduous forests of Thailand. The heat from the fire only affected the surface soil layer and did not cause any problems in deeper layers.

Spatial modelling of anthropogenic based peat land fire case study of the Kepulauan Meranti District

Forest fires in Indonesia are 99% due to human intentional factors. The practice of burning forests is done because it is easy, fast, and inexpensive, and the assumption that the ashes produced will fertilize the soil. The practice of burning forests is done primarily for the purpose of clearing agricultural land and plantations. Land and forest fires will be even worse if they occur on peat lands. Fires on peat lands consist of crown fire, surface fire, and ground fire which have a more severe impact on environmental, social and economic impacts. In terms of management, it is also more difficult and longer than fires on mineral land. On the other hand, pea tlands in Indonesia, 30%, are peat lands that have the potential for agricultural and plantation cultivation. The main objective of this paper is to use spatial modeling to provide an early warning system for forest fires on peat lands based on anthropogenic aspects in the Meranti Islands Regency, Riau Province. Data compiled based on anthropogenic aspects include: accessibility, population distribution, land clearing patterns, land use, and land status. Spatial analysis was carried out on anthropogenic aspects and the distribution of hotspots that had a level of confident (c> 80%). The results of the paper indicate that anthropogenic aspects that are dominant in the occurrence of forest fires are accessibility of road than river.

Damage assessment and reinforcement measures of prestress concrete bridge after fire

In order to provide reasonable advice for the maintenance and reinforcement of Bridges after fire, it is necessary to assess the damage of Bridges after fire. In this paper, the damage area of a fire-damaged concrete highway bridge is divided according to the concrete apparent detection, and the damage degree of different parts is determined. Carbonization depth and springback detection were used to determine the area and depth affected by fire. Based on the analysis of the surface fire temperature of components in different areas and the internal temperature of concrete, the degradation of the mechanical properties of concrete and steel bars is further deduced, and the damage assessment of the bridge performance is finally carried out.

Geospatial Modeling of Containment Probability for Escaped Wildfires in a Mediterranean Region.

Despite escalating expenditures in firefighting, extreme fire events continue to pose a major threat to ecosystem services and human communities in Mediterranean areas. Developing a safe and effective fire response is paramount to efficiently restrict fire spread, reduce negative effects to natural values, prevent residential housing losses, and avoid causalties. Though current fire policies in most countries demand full suppression, few studies have attempted to identify the strategic locations where firefighting efforts would likely contain catastrophic fire events. The success in containing those fires that escape initial attack is determined by diverse structural factors such as ground accessibility, airborne support, barriers to surface fire spread, and vegetation impedance. In this study, we predicted the success in fire containment across Catalonia (northeastern Spain) using a model generated with random forest from detailed geospatial data and a set of 73 fire perimeters for the period 2008-2016. The model attained a high predictive performance (AUC = 0.88), and the results were provided at fine resolution (25 m) for the entire study area (32,108 km2 ). The highest success rates were found in agricultural plains along the nonburnable barriers such as major road corridors and largest rivers. Low levels of containment likelihood were predicted for dense forest lands and steep-relief mountainous areas. The results can assist in suppression resource pre-positioning and extended attack decision making, but also in strategic fuels management oriented at creating defensive locations and fragmenting the landscape in operational firefighting areas. Our modeling workflow and methods may serve as a baseline to generate locally adapted models in fire-prone areas elsewhere.

Restoration Treatments Improve Overstory Tree Resistance Attributes and Growth in a Ponderosa Pine/Douglas-Fir Forest

Research Highlights: This study provides much needed insight into the development of resistance to disturbance and growth dynamics of overstory trees in response to restoration-based fuel reduction, and will be useful to scientists and managers attempting to better grasp the relative merits of restoration treatment types. Background and Objectives: Restoration-based fuel reduction treatments are common in dry, fire-prone forests of the western United States. The primary objective of such treatments is to immediately reduce a stand’s crown fire hazard. However, the impact of these treatments on residual trees is relevant to assess their longevity and resistance to future disturbances. In this study, we evaluate the effects of restoration on retained overstory ponderosa pine (Pinus ponderosa Lawson & C. Lawson) and Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees in western Montana, where treatments were experimentally implemented 13 years prior as part of the national Fire and Fire Surrogate study. Materials and Methods: We examined tree attributes in response to the following replicated treatments: thin-only, burn-only, thin + burn, and a no-action control. We analyzed three different tree attributes that confer resistance to common disturbances: height-to-diameter ratio (resistance to wind), bark thickness (resistance to surface fire), and growth efficiency (resistance to bark beetles). Results: Our models suggest that thinning (with or without burning) alters tree attributes relative to the control in a manner that may increase tree resistance to wind and snow breakage, surface fire, and biotic agents such as bark beetles. Further analysis of annual growth of ponderosa pine and Douglas-fir varied by treatment type: thinning-based restoration (thin-only and thin + burn) increased diameter growth for both species, crown length and width in ponderosa pine, and crown length in Douglas-fir relative to unthinned treatments. Burning (burn-only and thin + burn) did not significantly affect tree growth relative to unburned treatments. Conclusions: While low-severity prescribed burning treatments are often used for restoration and have various ecosystem benefits, this study demonstrates that thinning (alone or in addition to burning) produces more measureable, beneficial results to overstory tree disturbance resistance metrics and growth.

Effectiveness of Restoration Treatments for Reducing Fuels and Increasing Understory Diversity in Shrubby Mixed-Conifer Forests of the Southern Rocky Mountains, USA

Exclusion of natural surface fires in warm/dry mixed-conifer forests of the western U.S. has increased potential for stand-replacing crown fires and reduced resilience of these systems to other disturbances, such as drought and insect attack. Tree thinning and the application of prescribed fire are commonly used to restore more resilient ecological conditions, but currently, there is a lack of long-term data with which to evaluate restoration treatment effectiveness in forest types where resprouting shrubs dominate understory communities. At a mixed-conifer site in southwestern Colorado, we compared forest structure and understory vegetation responses to three restoration treatments (thin/burn, burn, and control) over 10 years in a completely randomized and replicated experiment. Forest density, canopy cover, and crown fuel loads were consistently lower, and crown base height was higher, in thin/burn than burn or controls, but the effects diminished over time. Ten years following treatment, >99% of all plant species within both treatments and the control were native in origin. There were no differences between treatments in understory richness, diversity, cover, or surface fuels, but graminoid cover more than doubled in all treatments over the 15-year monitoring period. Similarly, there was more than a 250% increase post-treatment in shrub density, with the greatest increases in the thin/burn treatment. In addition, we saw an increase in the average shrub height for both treatments and the control, with shrub stems >80 cm becoming the dominant size class in the thin/burn treatment. Conifer seedling density was significantly lower in thin/burn compared with burn and control treatments after 10 years. Taken together, these conditions create challenges for managers aiming to reestablish natural fire patterns and sustain mixed-conifer forests. To limit the dominance of resprouting shrubs and facilitate conifer regeneration after overstory thinning and prescribed fire, managers may need to consider new or more intensive approaches to forest restoration, particularly given current and projected climate change.

Estimation of the surface area-to-volume ratios of litter components of the Brazilian rainforest and their impact on litter fire rate of spread and flammability

The surface-area-to-volume ratio (SAV) is a significant parameter in vegetation description, although different researchers have presented diverging estimates for forest litter. However, considering litter as a unique entity and disregarding the SAV of its components provides a misleading fire rate of spread. Undoubtedly, the leaves are more relevant than the twigs for the rate of spread of surface fires, as the former has a higher SAV. Therefore, based on the proven hyperdominance of tree species in the Brazilian rainforest, this work presents an accurate method to estimate the SAV. Furthermore, it demonstrates the critical role played by the SAV in the litter flammability and fire rate of spread assessments and shows that the leaf moisture content does not influence its SAV. Besides, comparing SAV data using the methodology presented herein with other authors’ assessments, the results differ by up to 49%. Finally, using the Brazilian rainforest litter in the methodologies of two distinct authors showed a difference of at least 36% in the results. The primary outcome of this study is the estimation of the SAV of leaves and thin, medium, and thick twigs, representative of the Brazilian rainforest, at 12,680 m−1, 1360 m−1, 620 m−1, and 310 m−1, respectively. The estimated SAV values are essential input data to numerical simulation models, and for comparison purposes with other authors’ work, the litter SAV is 8460 m−1.

Beyond slash‐and‐burn: The roles of human activities, altered hydrology and fuels in peat fires in Central Kalimantan, Indonesia

Near‐annual landscape‐scale fires in Indonesia's peatlands have caused severe air pollution, economic losses, and health impacts for millions of Southeast Asia residents. While the extent of fires across the peatland surface has been widely attributed to widespread peatland drainage for plantation agriculture, fires that transition from surface into sub‐surface soil‐based fires are the source of the most dangerous air pollution. Yet the mechanisms by which this transition occurs have rarely been considered, particularly in diversely managed landscapes. Integrating physical geography methods, including active fire scene evaluations and hydrological monitoring, with qualitative methods such as retrospective fire scene evaluations and semi‐structured interviews, this article discusses how and why sub‐surface peat fire transition occurs in an intensively altered peatland ecosystem in Indonesia's Central Kalimantan province. We demonstrate that variable water table levels and flammable surface vegetation (fire fuels) are co‐produced socio‐political and biophysical phenomena that enable the conditions in which surface fire is likely to transition into peat fire and increase landscape vulnerability to ongoing, uncontrollable annual fires. This localized understanding of peat fire transition counters normative causal narratives of tropical fire such as ‘slash‐and‐burn’, with implications for the management of new fire regimes in inhabited landscapes.

Tracking Pyrometeors With Meteorological Radar Using Unsupervised Machine Learning

AbstractPyrometeors are the large (>2 mm) debris lofted above wildfires that are composed of the by‐products of combustion of the fuels. One speciation of pyrometeor is firebrands, which are burning debris that lead to ignitions ahead of the surface fire and can be the dominant mechanism of fire spread and structure loss. Pyrometeors are observed by meteorological radar. To date, there have been no investigations into identification of pyrometeor speciation with radar. Here we present an unsupervised machine learning method (Gaussian mixture model) to classify pyrometeor modes using X‐band radar data. The coherent features of the mode of pyrometeor identified most likely to transport firebrands were tracked in time and space. The radar classification and tracking method shows that wildfires do produce signatures in radar returns that could be used for spot fire risk prediction. In wildfires, different types of debris (known as pyrometeors) are lofted in the smoke plumes and transported downwind. Some types of pyrometeors may, when in the air, still be burning and capable of starting new wildfires. Here we investigate the potential for meteorological radar to classify different types of pyrometeors and to track them to determine their potential for starting new fires downwind of the main fire front.

La mineralogía en la estimación de las temperaturas de los incendios forestales y sus efectos inmediatos en Andosoles, Estado de México

El fuego es un fenómeno natural e indispensable dentro de los ciclos biogeoquímicos de los suelos, sobre todo aquellos que sustentan una vegetación forestal como los Andosoles. No obstante, poco se conoce sobre las temperaturas que se alcanzan en el suelo y su efecto inmediato sobre sus propiedades edáficas. En 2017 se realizaron recorridos de campo en Texcoco, Estado de México, dos días después de que ocurrió un incendio forestal en Quercus sp y Pinus sp. Muestras de suelo compuestas e inalteradas se colectaron en los primeros 5 cm de suelo para el análisis de sus propiedades edáficas y micro-morfológicas. La estimación de la temperatura se realizó a través de un experimento térmico y análisis mineralógico. Con base en la destrucción, formación y dominancia principalmente de óxidos, ferromagnesianos y pseudoarenas, las temperaturas alcanzadas en los incendios forestales se agruparon en: < 250 °C en incendios superficiales y de copa de cualquier tipo de vegetación y 250 °C - 500 °C cuando árboles caídos y raíces de árboles continuaron incinerándose. Materia orgánica, pH, capacidad de intercambio catiónico, P, K+ y Na+ y textura muestran tendencias directas e indirectas de acuerdo con el tipo de cenizas y temperatura y no con la severidad y tipo de vegetación. Los incendios superficiales y de copa modificaron de inmediato las propiedades de los Andosoles y mejoraron su calidad, mientras que, en aquellos puntos donde se alcanzaron temperaturas más altas, el suelo se vio afectado, pero esta perturbación se considera de menor impacto por presentarse en áreas reducidas.

Analyzing of the Situation with Forest Fires in the Primorsky Region

Forest fire is a terrible disaster. Even a surface fire, leads to the fact that the forest planting passes into the stage of weakened, unproductive, which requires centuries to recover, as a result of the fire, the undergrowth dies, the habitats of animals and birds are destroyed, and the CO2 emission into the atmosphere grows. Currently, information is increasingly being received that many countries suffer from forest fires, Russia among them. The situation with fires in the Primorsky Territory is complicated due to the small number of forest protection, landscape, the large number of abandoned agricultural land and the presence of a large number of forest fund tenants. There is no well-coordinated work on fire detection, patrolling the territory with a small number of forest guards is impossible, satellite monitoring allows you to detect a fire when a deflagration is already gaining strength and it is difficult to determine the accessibility, and often the possibility of access to the fire, by coordinates. Most of the region’s state forest fund has been leased, tenants do not always have good neighborly relations with local residents, if all kinds of conflicts arise, then revenge or set fire to become synonymous with words. And often hiding a crime scene in the forest with a fire is a way to avoid punishment.

Parameter Estimation for the Forest Fire Propagation Model

Abstract This paper first gives a brief overview of the Lagrangian forest fire propagation model [Ambroz, M.—Balažovjech, M.—Medl’a, M.—Mikula, K.: Numerical modeling of wildland surface fire propagation by evolving surface curves, Adv. Comput. Math. 45 (2019), no. 2, 1067–1103], which we apply to grass-field areas. Then, we aim to estimate the optimal model parameters. To achieve this goal, we use data assimilation of the measured data. From the data, we are able to estimate the normal velocity of the fire front (rate of spread), dominant wind direction and selected model parameters. In the data assimilation process, we use the Hausdorff distance as well as the Mean Hausdorff distance as a criterion. Moreover, we predict the fire propagation in small time intervals.