Wildland Fire

Integral to the reproductive processes of the biota of several forest, shrub, and grassland biome-types, wildfire ignites some 3,400,000km2 of Earth’s vegetated surface annually. Though a highly complex phenomena coupled with not one, but several Earth systems, human actions are both directly and indirectly changing wildfire frequencies, intensities, severities, and behaviours, and to the detriment of both environment and society. Nowhere is this felt more so than the wildland urban interface, which home to roughly 1/3 of the nation’s populous and 40% of its housing stock, is the fastest-growing land-use type in the conterminous United States. A place where fire-averse architectures meet increasingly fire-prone lands, loss of lives, properties, and livelihoods to a series of wildfire complexes of proportions unprecedented in living memory have rendered there an urgent need to reconsider the challenge of living with wildfire as a vital landscape process. The product of a transdisciplinary study which converged state-of-the-knowledge from fields as diverse as the fire, ecological, and wider Earth sciences; information, communication, computing, and related technologies, both digital and biological; evolutionary, smart and living materials, architectures, and urban systems; philosophy, anthropology, psychology, and policymaking, this thesis presents a new wildland urban interface paradigm modelled on the biochemistries, behaviours, and systems of fire-adapted flora and the fire regimes they form. Migrating biomimetics from the level of species to systems, relying not on generic notions of nature and its workings, nor assumptions more generally, but on rigorous interrogation of the interplay between biotic and abiotic processes from the molecular to landscape to planetary scale, and across both human and geological timescales, several original theoretical and technical architectural and urban concepts are discussed, together with their possible applications and implications both within and beyond the wildland urban interface. Integrating insights from local and global indigenous and ancient fire cultures, the findings conclude that not merely is a reconciliation of human and non-human systems at the interface of fire-prone wild and urban lands possible, but therein resides potent ecological, social, and technical potentialities that merit further research in the years ahead.

Chapter Overview: Transcending the boundaries of space and time, whereas the 5-part case studies series is exclusively focused on recent western U.S. wildfire complexes and the future WUI insights as can be gleaned therefrom, this triangulated case study extends across continents and centuries to discuss parallels between events that have historically been considered as mutually exclusive, therein studied in silos. Traversing transdisciplinary information as relates to both wildland and urban fires, a system of systems approach is employed by means of illuminating how, at the level of biochemistry, physics, and the wider sciences, fire behaviours as are witnessed in wildlands have become manifest in cities past and present, and why the matter thereof it pertinent to architectural and urban design futures. While informing the new WUI paradigm this thesis puts forth, the purpose of this chapter is that of highlighting the wider applicability of the findings of this research programme, and of critiquing construction, and other built environment concepts as evidence vulnerability to fire.

An Autonomous Fire Detector (AFD) is a miniature electronic package combining position location capability [using the Global Positioning System (GPS)], communications (packet or voice-synthesized radio), and fire detection capability (thermal, gas, smoke detector) into an inexpensive, deployable package. The AFD can report fire-related parameters, like temperature, carbon monoxide concentration, or smoke levels via a radio link to firefighters located on the ground. These systems are designed to be inserted into the fire by spotter planes at a fire site or positioned by firefighters already on the ground. AFDs can also be used as early warning devices near critical assets in the urban-wildland interface. AFDs can now be made with commercial off-the-shelf components. Using modern micro-electronics, an AFD can operate for the duration of even the longest fire (weeks) using a simple dry battery pack, and can be designed to have a transmitting range of up to several kilometers with current low power radio communication technology. A receiver to capture the data stream from the AFD can be made as light, inexpensive and portable as the AFD itself. Inexpensive portable repeaters can be used to extend the range of the AFD and to coordinate many probes into an autonomous fire monitoring network.

The parameter terms (second column) for log (Aerial shrub cover + 1) × scale and log (Aerial tree cover + 1) × scale were incorrectly given positive rather than negative values. The correct values are: log (Aerial shrub cover + 1) × scale = −0.005 (0.002) log (Aerial tree cover + 1) × scale = −0.002 (0.001)

Daily weather data (since 1939) from four localities in the south-eastern, coastal part of the Cape Floral Kingdom ('south-eastern-CFK') were used to calculate daily fire danger indices (FDIs). Cloud-to-ground lightning strike distributions (2006-10) were explored for geographical and temporal trends. Low or moderate fire danger conditions were the norm year round, and even large fires occurred under these conditions. Lightning occurred throughout the landscape at fairly low densities (mean ¼ 0.4 strikes km À2 year À1 ) and in all seasons, increasing somewhat during summer. Lightning presence increased with increasing rainfall, relative humidity, temperature and wind speed. Lightning seasonality in the south-eastern-CFK did not differ from that in the south-western-CFK. Our results provide evidence of a largely aseasonal fire regime in eastern coastal fynbos shrublands: FDIs peaked in winter (due to low rainfall and hot, dry katabatic winds) but were not associated with a winter fire regime; lightning and the co-occurrence of lightning and elevated FDIs were aseasonal and were correlated with the incidence of lightning-ignited fires throughout the year. The implication for management is that season of burn is largely unimportant. Mean annual FDI increased significantly over the study period, a trend which is likely to manifest in increased frequency and severity of fire, some of which has already been observed.

Despite evident advances in knowledge and understanding concerning the application of prescribed burning for delivering benefits in wildfire control and a variety of sociocultural, economic and environmental outcomes, the practical application of prescribed burning in Australia is increasingly administratively and logistically complex, often controversial and climatically challenging. This series of papers does not address the merits or otherwise of prescribed burning – we accept the lessons from antiquity and recent history that the use of prescribed fire in contemporary Australia is essential for reducing, although not always being able to deliver on, wildfire risks and meeting a variety of societal and environmental needs. This special issue focuses on several fundamental adaptive management and monitoring questions: are we setting appropriate management targets? Can these targets and associated indicators be readily measured? Can we realistically deliver on those targets? And if...

Safety is typically talked about in a context of the absence of injury. The field of resilience engineering has been advocating that we think about safety differently, by taking a systems view and begin to see how people create safety in unsafe systems by managing risk. There is growing recognition that safety is an emergent behavior of our complex system of human performance. A model of human performance focused on resilience and adaptation will be presented. The ability to learn and adapt is at the heart of individual and organizational high performance. Kurt Lewin is often recognized as "the founder of modern social psychology." Over 60 years ago Lewin, in his classic model of how people make significant change, pointed out the importance of providing psychological safety. In his model, psychological safety is essential to reduce learning anxiety. In short, psychological safety is necessary for learning to take place. Related to this conference theme, storytelling only takes place within a container of psychological safety. Without psychological safety, there is no story telling. This paper explores the crucial but often ignored ingredient to making profound change (individual and organizational)-the concept and application of psychological safety: what it is, why it's important, and how to cultivate it.

In this paper, the architecture and the application of a system designed for the assessment of the distribution of dynamic wildland fire risk over the whole Italian territory are presented. Such an assessment takes place on the basis of static information concerning the vegetation cover and the topography of the territory and of dynamic information consisting of the meteorological forecast, over a certain time horizon, provided by a Limited Area Model. The risk distribution assessment is obtained through the use of two different models, namely the fuel moisture model and the potential fire spread model, which are applied, at each time interval, for each of the cells in which the area of study is discretized. In this paper, the structure of such models is presented in detail, and similarities and differences with respect to other existing models are discussed. As the performance of the overall system is heavily dependent on the choice of the values of the parameters appearing in such models, a careful calibration of such parameters is needed. In this respect, the results provided by a preliminary calibration are presented, carried out with the objective of maximizing the accordance between the outputs of the presented risk assessment system and the information relevant to really occurred fires.

Vegetation cover is a heterogeneous medium composed of different kinds of fuels and non-combustible parts. Some properties of real fires arise from this heterogeneity. Creating heterogeneous fuel areas may be useful both in land management and in firefighting by reducing fire intensity and fire rate of spread. The spreading of a fire through a heterogeneous medium was studied with a two-dimensional reaction–diffusion physical model of fire spread. Randomly distributed combustible and non-combustible square elements constituted the heterogeneous fuel. Two main characteristics of the fire were directly computed by the model: the size of the zone influenced by the heat transferred from the fire front and the ignition condition of vegetation. The model was able to provide rate of fire spread, temperature distribution and energy transfers. The influence on the fire properties of the ratio between the amount of combustible elements and the total amount of elements was studied. The results...

Mastication of woody shrubs is used increasingly as a management option to reduce fire risk at the wildland-urban interface. Whether the resulting mulch layer leads to extreme soil heating, if burned, is unknown. We measured temperature profiles in a clay loam soil during burning of Arctostaphylos residues. Four mulch depths were burned (0, 2.5, 7.5 and 12.5 cm), spanning typical conditions at forested sites in northern California with dense pre-mastication shrub cover. Two soil moisture contents were compared at each fuel depth to simulate spring prescribed burning (moist soil) and late-season wildfire (dry soil). Maximum temperatures reached 600 • C on the surface of dry soils and were 100-200 • C lower for moist soil. Heating was extensive in dry soil for the two deepest mulch depths, exceeding the lethal threshold for plants (60 • C) for a minimum of 7 h throughout the 10-cm soil profile. Minimal heat pulse was found with less mulch. Moist soil also dampened heat penetration; peak temperatures exceeded 60 • C only to 2.5 cm in the soil profile for all but the deepest mulch layer. No adverse effects of burning on water repellency were found in dry or moist soil. The potential for biological damage from soil heating during fire exists following mastication, particularly in dry soil with a mulch depth of 7.5 cm or greater. Field projections indicate that up to one-fourth of treated areas with dense pre-mastication vegetation would surpass lethal soil temperatures during a surface wildfire.

The United States’ National Cohesive Wildfire Management Strategy aims to achieve greater social and ecological resilience to wildfire. It also raises the question: cohesive for whom and for what purpose? In this article, we address the wildfire response goal and what a cohesive response means. Namely, we define a cohesive response as the ability to co-manage across scales for a more effective wildfire response. Our approach is grounded in the reality of the growing complexity of wildfire – both biophysically and socio-politically. We suggest that suppression and fire operations are necessary, but insufficient in the face of this growing complexity as we seek safer and effective wildfire response. Using network-based concepts and drawing from the literature on socio-ecological resilience, we consider how scales can be matched, what can and should be communicated across scales, and what this means for creating more adaptable institutions for more effective wildfire response. Survey r...

Smoke pollution from wildfires can adversely affect human health, and there is uncertainty about the amount of smoke pollution caused by prescribed v. wildfires, a problem demanding a landscape perspective given that air quality monitoring is sparse outside of urban airsheds. The primary objective was to assess differences in fire intensity and smoke plume area between prescribed fires and wildfires around Melbourne and Sydney, Australia. We matched thermal anomaly satellite data to databases of fires in forests surrounding both cities. For each matched fire we determined hotspot count and quantified their intensity using the fire radiative power (FRP) measurement. Smoke plumes were mapped using MODIS true colour images. Wildfires had more extreme fire intensity values than did prescribed burns and the mean size of wildfire plumes was six times greater than of prescribed fire plumes for both cities. Statistical modelling showed that the horizontal area covered by smoke plumes could be predicted by hotspot count and sum of FRP, with differences between cities and fire type. Smoke plumes from both fire types reached both urban areas, and particulate pollution was higher on days affected by smoke plumes. Our results suggested that prescribed fires produced smaller smoke plume areas than did wildfires in two different flammable landscapes. Smoke plume and FRP data, combined with air pollution data from static monitors, can be used to improve smoke management for human health.

This is a review of the most important work in wildland fire mathematical modelling which has been carried out at different research centres around the world from the beginning of the 1940s to the present. A generic classification is proposed which allows wildland fire models to be sorted. Surface fire spread models, crown fire initiation and spread models, spotting and ground fire models are reviewed historically and the most significant ones are analysed in depth. The last two sections are dedicated to wildland fire behaviour calculation systems based on the reviewed models. The evolution and complexity of these systems is analysed in parallel with the development of new technologies. Special attention is given to the tools most commonly in current use by forestry agencies. q

The feasibility and fundamentals of forest fire detection by smoke sensing with single-wavelength lidar are discussed with reference to results of 532-nm lidar measurements of smoke plumes from experimental forest fires in Portugal within the scope of the Gestosa 2001 project. The investigations included tracing smoke-plume evolution, estimating forest-fire alarm promptness, and smoke-plume location by azimuth rastering of the lidar optical axis. The possibility of locating a smoke plume whose source is out of line of sight and detection under extremely unfavourable visibility conditions was also demonstrated. The eye hazard problem is addressed and three possibilities of providing eye-safety conditions without loss of lidar sensitivity (namely, using a low energy-per-pulse and high repetition-rate laser, an expanded laser beam, or eye-safe radiation) are discussed.

Five methods for the evaluation of fire danger, based on meteorological factors, were tested using statistical data for daily number of fires and burned area from six different regions in France, Italy and Portugal, for a period of 39 years, both for Winter and Summer fires. A normalised scale for the output of the various methods was adopted to compare the variation of number of fires and burned area predicted by each method. Based on a statistical test, the relative performance of the various methods is assessed. From the five methods that were analysed in this research, the Canadian and the modified Nesterov methods showed the best overall performance.

Apart from voice services, data made its foray in cellular networks with 2.5G networks. Today, with 3G network already in place, the data requirements of mobile subscribers is very high. With the increasing demand for mobile internet and rich data services such as streaming media for audio and video, this data requirement is expected to multifold in near future.  Correspondingly the network operators have started looking for alternative means of satisfying these data needs. Among many alternatives, mobile data offloading (MDO) is the most promising one. This paper presents the extensive need,  benefits, and technological solutions for MDO. Qualitatively, it is also shown that Wi-Fi, or 802.11 network is the most
promising technology for MDO. Also, to further popularize Wi-Fi as a candidate network for MDO, IEEE published the enhancements to the base IEEE 802.11-2007 standard in the form of its ninth amendment (i.e. IEEE 802.11u). Restricting the scope to beacon frame only, we show how this amendment supports interworking of 802.11 network with external networks. We also show the benefit of 802.11u compatible
Wi-Fi, as a candidate network for MDO, by modelling the problem of taking user's choice for assisting any vertical handover decision algorithm.

Norm theory offers a paradigm for understanding why the public judges management actions acceptable or unacceptable. This study assesses normative beliefs about acceptable wildland fire management. The acceptability of three fire management actions for eight scenarios was examined. The scenarios varied by fire origin and fire impact on air quality, private property, forest recovery, and outdoor recreation. The data were obtained from a mail survey of visitors to three national forests: (a) Arapaho-Roosevelt, Colorado (n = 469), (b) Mt. Baker-Snoqualmie, Washington (n = 498), and (b) San Bernardino, California (n = 321). Results of a mixed design ANOVA indicated that the acceptability of wildland fire management actions 1 varied according to the fire scenario evaluated, but substantive differences in normative beliefs were not noted among the three forests. Chi-square analyses identified differences in normative agreement for fire management actions across scenarios but did not reveal substantive differences in normative agreement between forests.

This study examines the degree to which the use of the Incident Command System (ICS) influenced the performance of Texas emergency operations centers (EOCs) during Hurricane Rita. Staff in evacuation, transition, and host county EOCs completed a questionnaire that assessed demographic variables, EOC physical environment, ICS experience, ICS implementation, and team climate. The results indicated that the duties each ICS section performed varied substantially from one EOC to another. Moreover, ICS experience and ICS implementation lacked statistically significant correlations with team climate, even though EOCs' physical environments did. Finally, staff from emergency relevant agencies (e.g., public works and social services) seemed to have more problems with ICS than did staff from emergency mission agencies (e.g., fire and police departments). Thus, there needs to be further study of ICS application in emergencies other than structural and wildland fires, as well as the development of new ICS training materials for emergency relevant agencies to supplement the current ICS training materials for emergency mission agencies.

Wildfires that spread into wildland-urban interface (WUI) communities present significant challenges on several fronts. In the United States, the WUI accounts for a significant portion of wildland fire suppression and wildland fuel treatment costs. Methods to reduce structure losses are focussed on fuel treatments in either wildland fuels or residential fuels. There is a need for a well-characterised, systematic testing of these approaches across a range of community and structure types and fire conditions. Laboratory experiments, field measurements and fire behaviour models can be used to better determine the exposure conditions faced by communities and structures. The outcome of such an effort would be proven fuel treatment techniques for wildland and residential fuels, risk assessment strategies, economic cost analysis models, and test methods with representative exposure conditions for fire-resistant building designs and materials.

The use of spatially explicit fire spread models to assess fire propagation and behaviour has several applications for fire management and research. We used the FARSITE simulator to predict the spread of a set of wildfires that occurred along an east–west gradient of the Euro-Mediterranean countries. The main purpose of this work was to evaluate the overall accuracy of the simulator and to quantify the effects of standard vs custom fuel models on fire simulation performance. We also analysed the effects of different fuel models and slope classes on the accuracy of FARSITE predictions. To run the simulations, several input layers describing each study area were acquired, and their effect on simulation outputs was analysed. Site-specific fuel models and canopy inputs were derived either from existing vegetation information and field sampling or through remote-sensing data. The custom fuel models produced an increase in simulation accuracy, and results were nearly unequivocal for all t...

Wildfire hazard abatement is one of the major reasons to use prescribed burning. Computer simulation, case studies, and analysis of the fire regime in the presence of active prescribed burning programs in forest and shrubland generally indicate that this fuel management tool facilitates fire suppression efforts by reducing the intensity, size and damage of wildfires. However, the conclusions that can be drawn from the above approaches are limited, highlighting the need for more properly designed experiments addressing this question. Fuel accumulation rate frequently limits prescribed fire effectiveness to a short post-treatment period (2-4 years). Optimisation of the spatial pattern of fire application is critical but has been poorly addressed by research, and practical management guidelines are lacking to initiate this. Furthermore, adequate treatment efforts in terms of fire protection are constrained by operational, social and ecological issues. The best results of prescribed fire application are likely to be attained in heterogeneous landscapes and in climates where the likelihood of extreme weather conditions is low. Conclusive statements concerning the hazard-reduction potential of prescribed fire are not easily generalised, and will ultimately depend on the overall efficiency of the entire fire management process.

The increasing extent of wildfires has prompted investigation into alternative fire management approaches to complement the traditional strategies of fire suppression and fuels manipulation. Wildfire prevention through ignition reduction is an approach with potential for success, but ignitions result from a variety of causes. If some ignition sources result in higher levels of area burned, then ignition prevention programmes could be optimised to target these distributions in space and time. We investigated the most common ignition causes in two southern California sub-regions, where humans are responsible for more than 95% of all fires, and asked whether these causes exhibited distinct spatial or intra-annual temporal patterns, or resulted in different extents of fire in 10–29-year periods, depending on sub-region. Different ignition causes had distinct spatial patterns and those that burned the most area tended to occur in autumn months. Both the number of fires and area burned va...

Evolutionary and paleoecological studies suggest that fires are natural in the Mediterranean basin. However, the important increase in the number of fires and area burned during the 20th century has created the perception that fires are disasters. In the present paper, we review to what extent fires are generating ecological disasters in the Mediterranean basin, in view of current fire regimes and the long-term human pressure on the landscapes. Specifically, we review studies on post-fire plant regeneration and soil ...

This paper reports results from a study of the flame characteristics of 22 wind-aided pine litter fires in a laboratory wind tunnel and 32 field fires in southern rough and litter-grass fuels. Flame characteristic and fire behaviour data from these fires, simple theoretical flame models and regression techniques are used to determine whether the data support the derived models. When the data do not support the models, alternative models are developed. The experimental fires are used to evaluate entrainment constants and air/fuel mass ratios in the model equations. Both the models and the experimental data are consistent with recently reported computational fluid dynamics simulations that suggest the existence of buoyancy-and convection-controlled regimes of fire behaviour. The results also suggest these regimes are delimited by a critical value of Byram's convection number. Flame heights and air/fuel ratios behave similarly in the laboratory and field, but flame tilt angle relationships differ.

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This paper details the properties of OPAN fiber, how to process the fiber and describes various end use applications and the test methodologies used to characterize OPAN based products..

Strategies, models, and algorithms facilitating such models are explored to provide transportation network managers and planners with more flexibility under uncertainty. Network design problems with non-stationary stochastic OD demand are formulated as real option investment problems and dynamic programming solution methodologies are used to obtain the value of flexibility to defer and re-design a network. The design premium is shown to reflect the opportunity cost of committing to a “preferred alternative” in transportation planning. Both network option and link option design problems are proposed with solution algorithms and tested on the classical Sioux Falls, SD network. Results indicate that allowing individual links to be deferred can have significant option value. A resource relocation model using non-stationary stochastic variables as chance constraints is proposed. The model is applied to air tanker relocation for initial attack of wildfires in California, and results show that the flexibility to switch locations with non-stationary stochastic variables providing 3-day or 7-day forecasts is more cost-effective than relocations without forecasting. Due to the computational costs of these more complex network models, a faster converging heuristic based on radial basis functions is evaluated for continuous network design problems for the Anaheim, CA network with a 31-dimensional decision variable. The algorithm is further modified and then proven to converge for multi-objective problems. Compared to other popular multi-objective solution algorithms in the literature such as the genetic algorithm, the proposed multi-objective radial basis function algorithm is shown to be most effective. The algorithm is applied to a flexible robust toll pricing problem, where toll pricing is proposed as a strategy to manage network robustness over multiple regimes of link capacity uncertainty. A link degradation simulation model is proposed that uses multivariate Bernoulli random variables to simulate correlated link failures. The solution to a multi-objective mean-variance toll pricing problem is obtained for the Sioux Falls network under low and high probability seasons, showing that the flexibility to adapt the Pareto set of toll solutions to changes in regime – e.g. hurricane seasons, security threat levels, etc – can increase value in terms of an epsilon indicator.

There has been considerable interest in the recent literature regarding the assessment of post-fire effects on forested areas within the North American boreal forest. Assessing the physical and ecological effects of fire in boreal forests has far-reaching implications for a variety of ecosystem processes -such as post-fire forest succession -and land management decisions. The present paper reviews past assessments and the studies presented in this special issue that have largely been based on the Composite Burn Index and differenced Normalized Burn Ratio (dNBR). Results from relating and mapping fire/burn severity within the boreal region have been variable, and are likely attributed, in part, to the wide variability in vegetation and terrain conditions that are characteristic of the region. Satellite remote sensing of post-fire effects alone without proper field calibration should be avoided. A sampling approach combining field and image values of burn condition is necessary for successful mapping of fire/burn severity. Satellite-based assessments of fire/burn severity, and in particular dNBR and related indices, need to be used judiciously and assessed for appropriateness based on the users' need. Issues unique to high latitudes also need to be considered when using satellite-derived information in the boreal forest region.

In this conceptual article, the authors explore the possibilities of another approach to examining the human dimensions of wildland fire. They argue that our understanding of this issue could be enhanced by considering a cultural studies construct known as the ''circuit of culture.'' This cross-disciplinary perspective provides increased analytic power by accounting for the meaningful role of 5 cultural processes in terms of their location and interrelation within social experience. The authors compare the circuit of culture approach with a body of recent literature focused on wildland fire. The authors make the case that this research has moved in a positive direction since wildland fire first ignited social scientific interest in the 1980s, but it is still missing key cultural processes. Ultimately, following the circuit allows us to make more nuanced statements about meaning, something much needed in the face of the wicked problem of wildland fire.

Old growth in the frequent-fire conifer forests of the western United States, such as those containing ponderosa pine (Pinus ponderosa), Jeffrey pine ( P. jeffreyi), giant sequoia (Sequioa giganteum) and other species, has undergone major changes since Euro-American settlement. Understanding past changes and anticipating future changes under different potential management scenarios are fundamental to developing ecologically based fuel reduction or

In the majority of US political settings wildland fire is still discussed as a negative force. Lacking from current wildfire discussions are estimates of the spatial extent of fire and their resultant emissions before the influences of Euro-American settlement and this is the focus of this work. We summarize the literature on fire history (fire rotation and fire return intervals) and past Native American burning practices to estimate past fire occurrence by vegetation type. Once past fire intervals were established they were divided into the area of each corresponding vegetation type to arrive at estimates of area burned annually. Finally, the First Order Fire Effects Model was used to estimate emissions. Approximately 1.8 million ha burned annually in California prehistorically (pre 1800). Our estimate of prehistoric annual area burned in California is 88% of the total annual wildfire area in the entire US during a decade (1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)) characterized as ''extreme'' regarding wildfires. The idea that US wildfire area of approximately two million ha annually is extreme is certainly a 20th or 21st century perspective. Skies were likely smoky much of the summer and fall in California during the prehistoric period. Increasing the spatial extent of fire in California is an important management objective. The best methods to significantly increase the area burned is to increase the use of wildland fire use (WFU) and appropriate management response (AMR) suppression fire in remote areas. Political support for increased use of WFU and AMR needs to occur at local, state, and federal levels because increasing the spatial scale of fire will increase smoke and inevitability, a few WFU or AMR fires will escape their predefined boundaries. #

National parks in western Canada experience wildland fire events at differing frequencies, intensities, and burn severities. These episodic disturbances have varying implications for various biotic and abiotic processes and patterns. To predict burn severity, the differenced Normalized Burn Ratio (dNBR) algorithm, derived from Landsat imagery, has been used extensively throughout the wildland fire community. In Canada, few accuracy assessments have been undertaken to compare the accuracy of the dNBR algorithm to its relative form (RdNBR). To investigate the accuracies of these two algorithms in Canada's National Parks, we hypothesized that RdNBR would outperform dNBR in two specific applications based on former research by . The first was the capacity of the RdNBR to produce more accurate results than dNBR over a wide range of fires and secondly in pre-fire landscapes with low canopy closure and high heterogeneity. To investigate these questions, dNBR and RdNBR indices were extracted from Landsat imagery and compared to the measurements of the Composite Burn Index . Following this, best fit models were developed and statistically tested at the individual, regional, overall, and vegetative levels. We then developed confusion matrices to assess the relative strength and weakness of each model. As an additional means of comparing model accuracy, we tested Hall et al.'s (2008) non-linear model in estimating burn severity for the study's western boreal region and individual fires. The results indicate that across all fires, the RdNBR-derived model did not estimate burn severity more accurately than dNBR (65.2% versus 70.2% classification accuracy, respectively) nor in the heterogeneous and low canopy cover landscapes. In addition, we conclude that RdNBR is no more effective than dNBR at the regional, individual, and fine-scale vegetation levels. The model was found to estimate burn severity in the western boreal region with a higher overall kappa than both the dNBR and RdNBR study models. The results herein support the continued research and pursuit of developing regional remote sensing derived models in western Canada.

An understanding of the environmental effects of the use of wildland fire retardant is needed to provide informed decision-making regarding forest management. We compiled data from all post-fire surface water monitoring programs where the fire retardant constituents ammonia, phosphorus, and cyanide were measured, and data were available in the public domain. For streams near four major wildfires, we evaluated whether these chemicals originated primarily from fire or from retardant use. We compared measured concentrations in streams where chemical wildland fire retardant was applied with concentrations in streams draining areas where retardant was not used. Correlations with calcium provided an additional line of evidence, because calcium concentrations in ash are much higher than in retardant. Ammonia, phosphorus, and total cyanide were found in streams in burned areas where retardant was not used, at concentrations similar to those found in areas where retardant was applied. Concentrations of weak acid dissociable cyanide were generally non-detected or very low, whether or not wildland fire retardant was used in the watershed. These results indicate that the application of wildland fire retardant had minimal effects on proximate surface water quality. Cyanide concentrations in post-fire stormwater runoff were not affected by the presence of ferrocyanide in the retardant formulas and were due to pyrogenic sources.

Forest thinning and prescribed fires are practices used by managers to address concerns over ecosystem degradation and severe wildland fire potential in dry forests. There is some debate, however, about treatment effectiveness in meeting management objectives as well as their ecological consequences. The purpose of this study was to assess changes to forest stand structure following thinning and prescribed fire treatments, alone and combined, in the eastern Cascade Mountains of Washington State. Treatments were applied to 12 management units, with each treatment combination replicated three times (including untreated controls). Thinning modified forest structure by reducing overall tree density by >60% and canopy bulk density by 50%, and increased canopy base height by $4 m, thereby reducing susceptibility to crown fire. The prescribed fire treatment, conversely, did not appreciably reduce tree density or canopy fuel loading, but was effective at increasing the density of standing dead trees, particularly when combined with thinning (37 snags/ha increase). Prescribed fire effects were more pronounced when used in combination with thinning. Thinning was more reliable for altering stand structure, but spring burning was lower in intensity and coverage than desired and may have led to results that downplay the efficacy of fire to meet forest restoration goals.

Appropriate use of satellite data in predicting >1 year post-fire effects requires remote measurement of surface properties that can be mechanistically related to ground measures of post-fire condition. The present study of burned ponderosa pine (Pinus ponderosa) forests in the Black Hills of South Dakota evaluates whether immediate fractional cover estimates of char, green vegetation and brown (non-photosynthetic) vegetation within a pixel are improved predictors of 1-year post-fire field measures, when compared with single-date and differenced Normalized Burn Ratio (NBR and dNBR) indices. The modeled estimate of immediate char fraction either equaled or outperformed all other immediate metrics in predicting 1-year post-fire effects. Brown cover fraction was a poor predictor of all effects (r 2 < 0.30), and each remote measure produced only poor predictions of crown scorch (r 2 < 0.20). Application of dNBR (1 year post) provided a considerable increase in regression performance for predicting tree survival. Immediate post-fire NBR or dNBR produced only marginal differences in predictions of all the 1-year post-fire effects, perhaps limiting the need for prefire imagery.Although further research is clearly warranted to evaluate fire effects data available 2-20 years after fire, char and green vegetation fractions may be viable alternatives to dNBR and similar indices to predict longer-term post-fire ecological effects.

In the California Sierra Nevada region, increased fire activity over the last 50 years has only occurred in the higher-elevation forests on US Forest Service (USFS) lands, and is not characteristic of the lower-elevation grasslands, woodlands and shrublands on state responsibility lands (Cal Fire). Increased fire activity on USFS lands was correlated with warmer and drier springs. Although this is consistent with recent global warming, we found an equally strong relationship between fire activity and climate in the first half of the 20th century. At lower elevations, warmer and drier conditions were not strongly tied to fire activity over the last 90 years, although prior-year precipitation was significant. It is hypothesised that the fire-climate relationship in forests is determined by climatic effects on spring and summer fuel moisture, with hotter and drier springs leading to a longer fire season and more extensive burning. In contrast, future fire activity in the foothills may ...

Wildland fire occurrence and behavior are complex phenomena involving essentially fuel (vegetation), topography, and weather. Fire managers around the world use a variety of systems to track and predict fire danger and fire behavior, at spatial scales that span from local to global extents, and temporal scales ranging from minutes to seasons. The fire management application determines the makeup of the planning tool, which usually incorporates one or more computer models. Advanced computing technology has spawned a new generation of fire planning tools to predict fire occurrence and fire behavior. We reviewed fire danger and fire behavior modeling systems from Australia, Europe, and North America, including operational tools that have been in use for decades, and newer models that profoundly enhance the spatial and temporal resolution of the resultant predictions. Linkages between these models and air quality models could very likely improve the mapping and prediction of air pollution due to wildland fires.