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Title: Systems for Environmental Management (SEM) / SEM
Language: English
Description: Systems for Environmental Management (SEM) is a Montana nonprofit research and educational corporation. They are specialized in issues concerning wildland fire planning, behavior, fuel, weather, and effects. Publications and software packages developed in cooperation with the Fire Sciences Laboratory of the USDA Forest Service Rocky Mountain Research Station are posted on the website. All items are freely available to download and use.
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Title: Universidad de Trás-os-Montes a Alto Douro (UTAD), Grupo de Fogos Florestais / Universidad de Trás-os-Montes a Alto Douro (UTAD), Forest Fire Group
Language: Portuguese
Description: The Forest Fire Group is an activity of the Department of Forest and Landscape at the Universidad de Trás-os-Montes e Alto Douro (UTAD). The Forest Fire Group was established in 1983 and has undertaken research in fuel and fire behavior modeling, fire risk and fire danger index, preventive silviculture and fuel management, controlled fire, adaptation and vulnerability of forests to fire.
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Title: Fire Star: a decision support system for fuel management and fire hazard reduction in mediterranean wildland-urban interfaces / Fire Star
Language: EnglishFrenchPortugueseSpanish
Description: Fire star is a decision support system for fuel management and fire hazard reduction in Mediterranean wildland-urban interfaces. It allows foresters, fire-fighters and engineering offices to assess the fire risk for exposed targets (people and houses) on these interfaces, and to test the preventive efficiency of the wildland fuel reduction. The predictions of advanced models of wildland fire behaviour and effects are the bases of the content of the Fire Star system. The researchers also pursued the following scientific objectives: to improve the methods of wildland fuel description and to develop Mediterranean fuel models, to enhance the predictive ability of the wildland fire behaviour model, and to improve the knowledge of wildland fire effects on the exposed targets. The project ran from 2002 to 2005.
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Title: Euromediterranean Wildland Fire Laboratory - EUFIRELAB / EUFIRELAB
Language: EnglishFinnishFrenchGreekItalianPortugueseSpanish
Description: The EUFIRELAB is a wall-less laboratory for wildland fire sciences and technologies in the euromediterranean region that enables knowledge and data exchange. The research units are divided into fuel description and modelling; wildland fire behavior modelling; fire ecology; socio-economy; decision support tools; meteorology; fire risks; fire suppression and wildland urban interfaces management. It aims to provide up-dated states of the art, to develop common methodologies and to propose answers to end-users. The products provided on the website are an E-library, E-observatories, news, forums, deliverables, jobs and CV, and specific studies related to wildland fire. The project ran from 2002 to 2006.
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Title: Prescribed burning demonstration site_UK_Dalwhinnie /
Language: English
Description: Provides a summary of a prescribed burn in Dalwhinnie, United Kingdom: purpose of treatment, location, burn conditions, site description and supporting documents of the demonstration site. The purpose of the treatment was experimental fires for determination of fire behaviour characteristics in heather.
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Title: Prescribed burning demonstration site_UK_Pentland Hills /
Language: English
Description: Provides a summary of a prescribed burn in Pentland Hills, United Kingdom: purpose of treatment, location, burn conditions, site description and supporting documents of the demonstration site. The purpose of the treatment was validation and further development of empirical fire behaviour models for FireBeaters project in heathland.
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Title: Fire, Fuel, and Smoke Science Program (FFS) / FFS
Language: English
Description: The Fire, Fuel, and Smoke Science Program of the Rocky Mountain Research Station is located at the Missoula Fire Sciences Laboratory in Missoula, Montana. The Program conducts international, cutting edge work in wildland fire research from fire physics to fire ecology. The Program performs work under its national charter to conduct fundamental and applied research relating to wildland fire processes, terrestrial and atmospheric effects of fire, and ecological adaptations to fire. In addition, the Program develops associated knowledge tools and applications for both managers and scientists. Original research includes: fire behavior prediction modeling, soil heating modeling and effects, landscape fire ecosystem dynamics, smoke emissions and dispersion modeling, and fire danger rating.
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Title: CSIRO Bushfire Team / Commonwealth Scientific and Industrial Research Organisation
Language: English
Description: CSIRO bushfire research is improving the understanding of fire, and improving technologies and strategies to save lives and limit damage. CSIRO has been involved in bushfire research for more than forty years. This has focused on: understanding and predicting bushfire behavior; the impact of bushfires on infrastructure; ecological responses to fire; the impact of climate change on bushfire risk; and pollutants and greenhouse gases as a result of bushfires.
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Title: D2.2-1 3D-Modelling of fire behaviour and effects /
Language: English
Description: This work is carried out within the context of the European integrated project “FIRE PARADOX”, the aim of this particular work package is to obtain a full-physical three-dimensional model of forest fire behaviour. The proposed approach accounts for the main physical phenomena involved in a forest fire by solving the conservation equations of physics applied to a medium composed of solid phases (vegetation) and gas mixture (combustion gases and the ambient air). The model consists in coupling the main mechanisms of thermal degradation (drying, pyrolysis and combustion) and of transfer (convection, diffusion, radiation, turbulence, etc.) taking place during forest fire propagation [1]. This multiphase complete physical approach already exists in 2D approximation [2] and consists in solving the described model in a vertical plane defined by the direction of fire propagation. The 3D extension of the existing model will enable to render the 3D effects observed in real fires and to represent the real heterogeneous structure of the vegetation. The parallelized CFD code under development is currently at the stage of predicting turbulent gas flows (within and above a forest canopy) and has been validated on several benchmarks of natural, forced and mixed convection.
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Title: D2.2-2 How to account for the heterogeneity of vegetation on fire behaviour and effects modelling /
Language: English
Description: The main objective of the present study was to evaluate the magnitude of vegetation heterogeneity effects on radiative transfer in forest fires. Especially we wanted to determine which heterogeneity sizes were important to consider either fuel description or fire modelling. We first considered these effects at shoot level (variations within several tens of centimetres) to identify which parameters describing needles distribution in pine shoots cause a significant departure from the usual extinction coefficient ( ). A study based on a shoot modelling approach (Stenberg 1996; Stenberg et al. 2001; Smolander & Stenberg 2001; Cescatti & Zorer 2003; Smolander & Stenberg 2003) was used for a computation of the STAR parameter based on architecture measurements for Pinus halepensis. Then we considered the effects of heterogeneity in patchy Mediterranean shrub land or tree canopies (Pinus halepensis, Pinus pinaster) at the scale of a clump of plants (variations within several meters), using field measurements and detailed tree architecture models (Caraglio et al. 1996; Barczi et al. 1997; Caraglio et al. 2006). For this purpose, the methodology used for solar radiation was adapted to fire radiation. In particular we investigated the effects of heterogeneity size and cover fraction for different bulk densities, on the heating of vegetation by radiation from a flaming zone of assumed dimensions. The results were analysed in terms of appropriate scale for fuel description and physical modelling, and specific method for physical modelling.
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Title: D2.2-2 How to account for the heterogeneity of vegetation on fire behaviour and effects modelling /
Language: English
Description: Wildland fires spread through vegetation which is a medium that can be very heterogeneous at several scales (Campbell & Norman 1997). The smallest scale is at shoot level, when needles or leaves are clumped around the shoot. The second scale is at branch level, when shoots are aggregated around a branch. The third one is at tree or shrub level. It defines the contour of vegetation. The last scale is the one of the stand. Energy budget dynamics under forest canopies are strongly influenced by the effects of spatial variability within the canopy on radiative and turbulent transfers (Hardy et al. 2004). In the wildland fire context, we assume that both radiative and convective transfer, as well as the combustion process, may be affected by fuel heterogeneity. Physically-based models for fire propagation are able to use vegetation spatial patterns described at a fine level in the mesh of solid phase (Dupuy & Morvan 2005; Linn et al. 2002) and to study how spatial patterns affect propagation (Linn et al. 2005). However, mesh size in calculation does not always entail to consider all kinds of heterogeneity, especially in shoot aggregation and understorey description. Moreover, mesh refinement is maybe not an appropriate objective because of plant fractal geometry (De Reffye et al. 1991; Knyazikhin et al. 1998). In addition, describing vegetation at these levels can be very time consuming (Cohen et al. 2004). Hence we could wonder whether or not details in vegetation patterns affect significantly fire behaviour, at least through radiation transfer. Indeed, radiation transfer in fires is a quite short distance heating, directly affected by the transmission by vegetation itself. For this reason, it is likely to be affected on average by small scale heterogeneity. Like in solar radiation transfer, the computation of radiation transfer in theoretical fire models is based on turbid media approximation (Albini 1985; Grishin 1997; Linn 1997; Morvan & Dupuy 2001; Cruz et al. 2006; see also Reviews by Pastor et al. 2003 and Sullivan et al. 2003), that is valid for a distribution of small planar elements, with negligible area and thickness. We will consider the effects of heterogeneity at both a shoot level and a plant clump level on radiation transfer in section 2. The convective transfer is the transfer of heat between the vegetation and the gaseous phase that results from the flow of air or hot gases over solid elements of vegetation, when the two media (fluid or vegetation) have different temperatures. The basic process of heat exchange is conduction (i.e. a very small scale process), but it is usually modelled at a macroscopic scale through a convection heat transfer coefficient, which depends on the flow properties and on geometrical properties of vegetation elements (Reynolds number). Any spatial variation in vegetation properties may cause variations of the fluid flow and in turn on the convective heat transfer, because it may affect the flow directly (through drag forces) or the heat transfer coefficient (through Reynolds number). Studies of wind flow over plant canopies in the atmospheric boundary layer have already shown that the smallest details of vegetation distribution (i.e. shoot level for pine tree) are not relevant to explain observed wind and turbulent variables profiles (Shaw & Patton, 2003). Indeed computations of wind flow based on the solution of Navier-Stokes equations can render observed profiles using a cell mesh an order of magnitude greater than these details. Typically, for tree canopies of at least 10 m height, using cells of 2 m side is enough. We also verified this assertion using the HIGRAD/FIRETEC model for fire behaviour that can be used to compute wind flows (see Appendix) We did not investigate the effects of small scale heterogeneity on the convective heat transfer coefficient, although for example strong clumping of needles in pine shoot may change significantly the local heat transfer coefficient as compared to a random distribution of ‘isolated’ needles. Indeed Michaletz and Johnson (2006a) showed that the tree foliage of conifers changes the heat transfer coefficient with respect to the one of ‘isolated’ elements But only the finest elements of vegetation participate in the propagation of fire and are characterized by a short response time (order of 1s or less) to a change in the fluid temperature. We expect that the response time be at most one order of magnitude higher with clumped needles (lower heat transfer coefficient). This should not affect significantly the temperature evolution of the finest elements of vegetation. Michaletz and Johnson (2006b) reached a similar conclusion, investigating crown sorch of several conifers, for foliage. They showed in addition that the conclusion is no longer valid for vegetative buds. Hence the details of vegetation elements should be considered for the purpose of predicting fire effects on trees. Due to small scale vegetation heterogeneity (tens of centimetres) is unlikely to produce significant effects on the structure of the flow we rather focused on the effects of larger scales like the one of tree crowns (a few meters). Moreover we only considered the effects of large scale heterogeneity on the overall fire behaviour as predicted by the HIGRAD/FIRETEC fire model (section 3) (i.e. including radiative and convective heat transfer, as well as combustion processes). Testing of the separate effect on convective transfer is an ongoing work. But due to we assume that radiation is much more a short distance process in fires (confirmed in section 2), we expect that the observed effects were mainly related to the effects on the flow. We derived recommendations for both fire behaviour modelling and vegetation description, which are proposed in section 4.
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Title: D2.4-1 Simulations of wildfire behaviour: 2D results /
Language: English
Description: This work is carried out within the context of the European integrated project “FIRE PARADOX”, aiming to obtain a fully physical three-dimensional model of forest fire behaviour. The development of this 3D code constitutes an extension of the 2D fire behaviour model FIRESTAR developed during a previous European project (EVG1-CT-2001). In this preliminary task, some physical sub-models have been modified, such as the turbulence and the combustion modelling, to improve the capability of this tool to reproduce the main characteristics observed during the propagation of a surface fire through a solid fuel layer. After a short introduction and a brief presentation of the set of equations constituting the physical model, some numerical results obtained in 2D for a surface fire propagating through an homogeneous (grassland) and an heterogeneous (shrubland) fuel layer, are analysed and compared with experimental and empirical data from the literature.
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Title: D2.4-2 Simulations of fire impact on tree foliage: 2D results /
Language: English
Description: The aim of the WP2.4 workpackage (activity 3) is to study numerically crown scorch and crown fire ignition as the effects of a fire line spreading through surface fuel under a tree canopy. Here we report a preliminary study performed with the FIRESTAR 2D model. The objective was to assess the usual assumptions made when one uses the Van Wagner criteria, based on plume theory, to estimate crown scorch or crown ignition. The Van Wagner criteria indeed are simple predictive models for crown scorch height or crown fire initiation occurrence. For this purpose we simulated the fire line by heat source put on the ground and mainly investigated the temperature field. As a first step we tested the sensitivity of the predictions to the mode of heat input and to the selected parameters of the k- turbulence model used in FIRESTAR. As a second step we ran computations of thermal plumes with no-wind and with no canopy, for first comparison to plume theory. The influence of crown existence to the temperature field above the heat source and, so way, to the crown scorch and fire ignition conditions, was then investigated. In the last part we show and discuss some results obtained in the presence of a wind.
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Title: Comportamiento del fuego en un pastizal del sitio ecológico ‘media loma’, región chaqueña occidental (Argentina) / Fire behaviour in grassland ecological site 'media loma', western Chaco region (Argentina)
Language: Spanish
Description: Fire behavior, considered a part of fire ecology, is together with fire prevention one of the two components of the ´fire triangle´ currently used as a basis for fire management and control. We assessed the fire behavior in a grassland located in the midland range ecological site in the Chaco region, northwestern Argentina. The site of the experiments was the ´La María´Experimental ranch, INTA Santiago del Estero Research Station, (28º 03’ S 64º 15’ E). Fire was applied in two study sites in 6 plots each. Fine fuel load, botanical composition, and fine fuel bulk density were estimated by sampling. Fire behavior was assessed by estimating forward rate of spread and flame length. These data were analysed using ANOVA with study site as independent variable. Correlation among variables was assessed using the Kendall’s ô correlation coefficient. Study sites presented a different botanical composition: plots were either dominated by Trichloris pluriflora (E.) Fournier, or by Pappophorum pappipherum (Lam.) Kuntze. Plant of these species possess different proportion of stems and leaves. These facts significantly affected fine fuel load, bulk density (p > F = 0,0001 in both cases) and the forward rate of spread (p > F = 0.0001). The latter was 27,62 m*min-1 in study site 1, where the first species dominated; and 21 m*.min-1 in study site 2, where the second dominated, respectively. Average flame length was 3,5 m, but reached 6 m when volatile shrubs ignited and participated in the propagation of fire. Correlations among forward rate of spread and fuel load with bulk density was positive and significant (p < 0,0001), but was not significant in the case of flame length. Fires were of high intensity and move fast and need blacklines or other indirect measures for control.
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