Wildland Fire Research Articles

Proposal of a fireproof design code for dwellings against the action of wildland fires

This study proposes a concept for the development of a fireproof design code for the verification of dwellings susceptible to wildfire action. There are currently structural codes for the design of buildings when subjected to indoor fires, outside fires that grow on the facade of buildings, and even fires in an accident situation due to ignitions with hydrocarbons or transportation vehicles. All of these security verification specifications are described in EC1:1–2. The current regulation in Portugal uses safety criteria and risk categories that are for indoor fires, therefore is very conservative and may not present an economic fireproof design against the action of wildfires. The aim of this work is a straight verification based on natural temperature characteristic curves that simulate wildfire heat flow by convection, radiation, and the deposits of firebrands.

Limiting conditions of smoldering-to-flaming transition of cellulose powder

Smoldering-to-flaming (StF) transition is an abrupt initiation of homogeneous gas-phase burning (i.e., flaming) preceded by heterogeneous solid-phase burning (i.e., smoldering), which can lead to fast spreading fires both in residential and wildland fires. Despite its hazard, StF transition remains difficult to predict because of its sensitive nature to external conditions, the inherent variability of porous biomass fuels, and a limited understanding of its dominating mechanisms. In this work, we apply a new experimental apparatus to investigate the limiting conditions of StF transition of uniform cellulose powders, at different oxidizer flow velocities (1.5–10.5 cm/s), oxygen concentrations (21, 19, 15, and 10%), and external heat fluxes (0–60 kW/m2). We find that the external heat flux required for StF transition increases as the O2 concentration decreases from 21% to 10% at fixed flow velocities, agreeing with both phenomenological arguments and a simplified energy balance. However, for a fixed O2 concentration, as the flow velocity increases, the required heat flux increases, due to the increased importance of convective heat losses. Furthermore, tests performed at 8% and 5% O2 do not undergo transition even at higher heat fluxes up to a threshold oxygen concentration of 10%. Under low-velocity conditions (airflow <5 cm/s), smoldering may still co-exist with a discrete weak blue flame because oxygen can diffuse into reacting (smoldering) cellulose powder. An oxidizer flow velocity of 5 cm/s appears to be a limiting value for the StF transition, at least for the present experimental conditions. It was also found that increasing the density of cellulose powder required a lower external heat flux for StF transition. This work advances the fundamental understanding of the StF transition, and thus helps guide the prevention of extreme fire events.

A Data-Fusion Approach to Assessing the Contribution of Wildland Fire Smoke to Fine Particulate Matter in California

The escalating frequency and severity of global wildfires necessitate an in-depth understanding and monitoring of wildfire smoke impacts, specifically its contribution to fine particulate matter (PM2.5). We propose a data-fusion method to study wildfire contribution to PM2.5 using satellite-derived smoke plume indicators and PM2.5 monitoring data. Our study incorporates two types of monitoring data, the high-quality but sparse Air Quality System (AQS) stations and the abundant but less accurate PurpleAir (PA) sensors that are gaining popularity among citizen scientists. We propose a multi-resolution spatiotemporal model specified in the spectral domain to calibrate the PA sensors against accurate AQS measurements, and leverage the two networks to estimate wildfire contribution to PM2.5 in California in 2020 and 2021. A Bayesian approach is taken to incorporate all uncertainties and our prior intuition that the dependence between networks, as well as the accuracy of PA network, vary by frequency. We find that 1% to 3% increase in PM2.5 concentration due to wildfire smoke, and that leveraging PA sensors improves accuracy.

Consequential lightning-caused wildfires and the “let burn” narrative

BackgroundCurrent guidance for implementation of United States federal wildland fire policy charges agencies with restoring and maintaining fire-adapted ecosystems while limiting the extent of wildfires that threaten life and property, weighed against the risks posed to firefighters. These ostensibly conflicting goals can make it difficult to clearly communicate specific response objectives of a given incident. Inherent ambiguity can expose land management agencies, like the United States Department of Agriculture Forest Service (USFS), to scrutiny when once remote, lightning-ignited wildfires burn across boundaries and result in damage. One such incident was the 2021 Tamarack Fire, ignited by lightning in a remote USFS wilderness area and ultimately burning 27,776 ha across multiple jurisdictions and destroying 25 structures. Intense sociopolitical interest developed around this incident, reigniting a “let burn” policy debate of the USFS despite this policy not formally existing. We provide a first approximation at quantifying the base rates of potentially consequently lightning-caused fires like the Tamarack Fire. We use multiple sources of fire-reporting data to characterize USFS fires from 2009 to 2020 by management-strategy to identify Tamarack Fire analogs. Within Incident Command System 209 (ICS-209) reports for fires originating on USFS lands, we identified 32 wildfires with similar key characteristics to the Tamarack Fire; nearly half ignited within wilderness areas.ResultsInitial strategies were driven by resource objectives for only six of the 32 wildfires; firefighter hazard mitigation was the primary driver of all others. No fire exhibited every characteristic of the Tamarack Fire. Analog fires accounted for a small percent (3.4%) of large (> 121 ha) USFS lightning-caused ignitions. These fires were responsible for 61.6% of structures destroyed and 25.8% of total personnel commitments of large lightning-caused USFS fires.ConclusionsLightning-ignited wildfires that could have resulted in sociopolitical controversy are rare, and those with strategies driven by resource objective are even rarer. More commonly, risks posed to firefighters from terrain, snags, or accessibility are factors driving strategy, even when fires ignite within wilderness areas. These results suggest that simple definitions of strategy such as those reported within the ICS-209 lack clarity and may increase sociopolitical pressure on the agency to continue aggressive fire exclusion strategies.

Laboratory quantification of firebrand generation from WUI fuels for model development

Firebrands play a critical role in the propagation of wildland fires, particularly in the wildland-urban interface (WUI). The mechanism behind fire spread by firebrands is not well understood despite being responsible for a majority of structure losses during WUI fires. This study quantifies the generation of firebrands from three typical WUI fuels (Douglas fir, eucalyptus globulus, and coast live oak) inside a laboratory-scale wind tunnel, to provide necessary data to model the spread of wildland fires into and within communities by burning embers. A comprehensive set of test conditions were considered, including the initial fuel mass, fuel moisture content, mean twig diameter, and crosswind speed. Results showed that the firebrand yields for all three fuel species were independent of the total dry mass lost, but positively correlated with the crosswind speed and negatively correlated to fuel moisture content and mean twig diameter. Meanwhile, the firebrand yields by mass of the fuels under the same test conditions have the following order: coast live oak >Douglas fir >eucalyptus globulus. Scaling analysis was performed to organize the data under different test conditions, and unique firebrand yield correlations were then obtained for each fuel species. In addition, the masses and projected areas of the firebrands for each fuel species had a linear fitting correlation, and the slope of the fitting line was positively correlated to fuel moisture content but insensitive to crosswind speed and mean twig diameter. The data and correlations disclosed in this study could be vital for future simulations of fire spread in both the wildland and WUI.

Analysis of Fire-Induced Circulations during the FireFlux2 Experiment

Despite recent advances in both coupled fire modeling and measurement techniques to sample the fire environment, the fire–atmosphere coupling mechanisms that lead to fast propagating wildfires remain poorly understood. This knowledge gap adversely affects fire management when wildland fires propagate unexpectedly rapidly and shift direction due to the fire impacts on local wind conditions. In this work, we utilized observational data from the FireFlux2 prescribed burn and numerical simulations performed with a coupled fire–atmosphere model WRF-SFIRE to assess the small-scale impacts of fire on local micrometeorology under moderate wind conditions (10–12 m/s). The FireFlux2 prescribed burn provided a comprehensive observational dataset with in situ meteorological observations as well as IR measurements of fire progression. To directly quantify the effects of fire–atmosphere interactions, two WRF-SFIRE simulations were executed. One simulation was run in a two-way coupled mode in which the heat and moisture fluxes emitted from the fire were injected into the atmosphere, and the other simulation was performed in a one-way coupled mode for which the atmosphere was not affected by the fire. The difference between these two simulations was used to analyze and quantify the fire impacts on the atmospheric circulation at different sections of the fire front. The fire-released heat fluxes resulted in vertical velocities as high as 10.8 m/s at the highest measurement level (20 m above ground level) gradually diminishing with height and dropping to 7.9 m/s at 5.77 m. The fire-induced horizontal winds indicated the strongest fire-induced flow at the lowest measurement levels (as high as 3.3 m/s) gradually decreasing to less than 1 m/s at 20 m above ground level. The analysis of the simulated flow indicates significant differences between the fire-induced circulation at the fire head and on the flanks. The fire-induced circulation was much stronger near the fire head than at the flanks, where the fire did not produce particularly strong cross-fire flow and did not significantly change the lateral fire progression. However, at the head of the fire the fire-induced winds blowing across the front were the strongest and significantly accelerated fire progression. The two-way coupled simulation including the fire-induced winds produced 36.2% faster fire propagation than the one-way coupled run, and more realistically represented the fire progression.

Biomass smoke inhalation promotes neuroinflammatory and metabolomic temporal changes in the hippocampus of female mice

Smoke from wildland fires has been shown to produce neuroinflammation in preclinical models, characterized by neural infiltrations of neutrophils and monocytes, as well as altered neurovascular endothelial phenotypes. To address the longevity of such outcomes, the present study examined the temporal dynamics of neuroinflammation and metabolomics after inhalation exposures from biomass-derived smoke. 2-month-old female C57BL/6 J mice were exposed to wood smoke every other day for 2 weeks at an average exposure concentration of 0.5 mg/m3. Subsequent serial euthanasia occurred at 1-, 3-, 7-, 14-, and 28-day post-exposure. Flow cytometry of right hemispheres revealed two endothelial populations of CD31Hi and CD31Med expressors, with wood smoke inhalation causing an increased proportion of CD31Hi. These populations of CD31Hi and CD31Med were associated with an anti-inflammatory and pro-inflammatory response, respectively, and their inflammatory profiles were largely resolved by the 28-day mark. However, activated microglial populations (CD11b+/CD45low) remained higher in wood smoke-exposed mice than controls at day 28. Infiltrating neutrophil populations decreased to levels below controls by day 28. However, the MHC-II expression of the peripheral immune infiltrate remained high, and the population of neutrophils retained an increased expression of CD45, Ly6C, and MHC-II. Utilizing an unbiased approach examining the metabolomic alterations, we observed notable hippocampal perturbations in neurotransmitter and signaling molecules, such as glutamate, quinolinic acid, and 5-α-dihydroprogesterone. Utilizing a targeted panel designed to explore the aging-associated NAD+ metabolic pathway, wood smoke exposure drove fluctuations and compensations across the 28-day time course, ending with decreased hippocampal NAD+ abundance on day 28. Summarily, these results indicate a highly dynamic neuroinflammatory environment, with potential resolution extending past 28 days, the implications of which may include long-term behavioral changes, systemic and neurological sequalae directly associated with wildfire smoke exposure.

Inspiration to act or just another scary vision?

Images are powerful communicators. They evoke feelings, raise awareness of important issues and sometimes spur people to act. A critical societal issue that may benefit from all these kinds of engagement is climate change. This paper presents a study of images accompanying news items on the current state of our climate as expressed in the IPCC’s Sixth Assessment Report. The items were culled from five Norwegian and five UK news sources, and the images were analysed in terms of topic and news value. Unsurprisingly, climate impact topics were common in both countries, with bush and forest fires dominating. Thus, the traditional news values of Negativity and Impact were the most important ones drawn on. More surprisingly, the Norwegian material comprised a high number of images of politicians, representing the news value of Eliteness. This topic was absent in the UK material. Pictures that may point to climate solutions, e.g. new energy sources or lifestyle matters, were only sparsely represented. Thus, the images may ensure people’s engagement with climate change through disaster scenarios, but few seem to have the potential to motivate action.

Burning Rate of Wood Cribs with Controlled Airflow

AbstractThere is a dire need to improve our prediction capabilities of wildland fire behavior in a range of conditions from marginal burning to the most extreme. In order to develop a more physically-based operational wildland fire behavior model, we need to improve our understanding of the effect of ventilation on burning rate of fuel beds. In this work, wood cribs are used as a simplified fuel bed. A variety of crib designs were tested with stick sizes ranging from 0.32 cm to 1.27 cm and porosities ranging from densely packed to loosely packed. A pressurized box was built that allowed for a controlled flow rate of air through the cribs from 100 LPM to 1000 LPM. The mass loss rates with forced ventilation were compared to tests conducted outside of the box under unrestricted quiescent conditions. For the flow rates tested here, the burning rate was generally observed to increase with flow. The amount of air naturally induced into a crib while burning was deduced to be best related to the vent area and the square root of the stick spacing (Avs1/2). It was seen that the air-to-fuel ratio inside a fuel bed burning in quiescent conditions is approximately 1.11, indicating that over 75% of the air required to completely combust the pyrolysis gases is entrained in the plume. When the supplied air is less than the amount normally entrained in ambient burning, the crib is under-ventilated and the proportional reduction in the burning rate does not seem to depend on the crib characteristics. When the crib is over-ventilated, however, the relative increase in the burning rate does vary with crib design. Simple physical arguments were used to correlate the data. Future work will include testing at higher flow rates, different moisture contents, and with cribs built with multiple stick thicknesses.

Mapping and spatial modeling of the passage of bush fires in a context of protected areas in northern Cameroon: contribution of time series of sentinel-2 images

Mapping and spatial modeling of the passage of bush fires in a context of protected areas in northern Cameroon: contribution of time series of sentinel-2 images

Effects of Bush Fires on Biodiversity in West Africa Sahel: A Review

Bush fire is one of the drivers of biodiversity loss worldwide. However, the impact of bush fires on biodiversity in the West Africa Sahel is not well documented. Therefore, this study reviewed the effects of bush fires on biodiversity, the typology of the bush fire drivers and bush fires solutions in the West Africa Sahel via a systematic review. The authors used many research engines such as Google Scholar and Mendeley from 2010 to 2022 with some keywords in French and English. It comes from the analysis of the data that Mali is the most country affected by bush fires with an average of 35,000,000 ha burned. In Burkina Faso, bush fires burned more than 2 million hectares each year. The analysis showed also a loss of 1,675,157 ha in Niger and 56,568.10 ha in Senegal. The study recommends that climate actions should target bush fires prevention and fighting as climate response in order to promote sustainable biodiversity managementin the West Africa Sahel. The study recommends also that West Africa Sahel countries develop bushfire community education programs for fire prevention.

Creative companionship as we face the apocalypse – an essay in conversation

This essay explores how a commitment to poetic collaboration, with daily writing and reading, changed the ways we perceived and lived our lives, particularly in light of living through the extremity of climate change (characterised by Australian bush fires and floods), and the isolation and stress caused by the pandemic. We explore collaboration, prose poetry and the creative process in the context of extremity, arguing that writerly collaboration can engender hope beyond the page. We discuss these topics in an essay-conversation format, moving back and forth between authors, building/ expanding/thinking and re-thinking through matters of process in light of the poetic and the extreme. Some of our creative works from this time are also included.

Attention-Based Wildland Fire Spread Modeling Using Fire-Tracking Satellite Observations

Modeling the spread of wildland fires is essential for assessing and managing fire risks. However, this task remains challenging due to the partially stochastic nature of fire behavior and the limited availability of observational data with high spatial and temporal resolutions. Herein, we propose an attention-based deep learning modeling approach that can be used to learn the complex behaviors of wildfires across different fire-prone regions. We integrate optimized spatial and channel attention modules with a convolutional neural network (CNN) modeling architecture and train the attention-based fire spread models using a recently derived fire-tracking satellite observational dataset in conjunction with corresponding fuel, terrain, and weather conditions. The evaluation results and their comparison with benchmark models, such as a deeper and more complex autoencoder model and the semi-empirical FARSITE fire behavior model, demonstrate the effectiveness of the attention-based models. These new data-driven fire spread models exhibit promising modeling performances in both the next-step prediction (i.e., predicting fire progression from one timestep earlier) and recursive prediction (i.e., recursively predicting final fire perimeters from initial ignition points) of observed large wildfires in California, and they provide a foundation for further practical applications including short-term active fire spread prediction and long-term fire risk assessment.

On the Growth of Wildland Fires from a Small Ignition Source

ABSTRACT Wildland and Wildland-Urban-Interface (WUI) fires are an important problem that may have major consequences in terms of safety, air quality, and damage to buildings, infrastructure, and the ecosystem. It is expected that with climate change, the wildland fire and WUI fire problem will only intensify. Wildland fires are often initiated by small ignition sources caused either by human intervention (hot metal fragments or burning biomass) or by natural events (lighting or sun heating). Once the wildfire or structural fire has been ignited and grows, it can spread rapidly through ember spotting, where pieces of burning materials are lifted by the plume of the fire and then transported forward by the wind, landing where they can start spot fires downwind. The ignition mechanisms for all of these fires have the common characteristic of a small and localized area of origin, with the subsequent spread of the fire to wider and larger areas. Because of the three-dimensional characteristics of this type of propagating fire, its rate of spread has an initial acceleration phase leading to an equilibrium rate of spread when the fire reaches a certain size, which is referred to as a “line-fire” type of spread. Most of the studies on wildland fire propagation have been conducted with line fires and have been concerned with characterizing the equilibrium rate of spread rather than the initial spread from a small ignition source. In this paper, some of the studies conducted to date on the subject of wildland fire growth from a small ignition source, and the physics supporting the mathematical expressions that are used to describe the growth of the fire are discussed. An attempt is also made to provide support for these works through a more fundamental approach to model the problem.

Impact of Urban Expansion on Coastal Vegetation Conservation in Buffalo City Metropolitan Municipality, South Africa

The ethical clearance certificate number for this research is KUL011SOLA01. This research elucidates the conceptualization of urbanization, urban sustainability, merits of coastal vegetation, and threats to urban expansion. Furthermore, this paper focuses on the analysis of the questionnaire, of which 300 copies were distributed to different categories of individuals in the study area, out of which a total of 254 copies were returned. The results revealed that 197 (80.7%) respondents confirmed the occurrence of environmental challenges, 33 (13.5%) others stated otherwise, while 14 (5.7%) claimed ignorance. Further, the researcher sought to know the causes of coastal vegetation loss; 190 (74.8%) respondents blamed it on urban expansion, 169 (66.8%) respondents stated it was due to deforestation activities. Other views cited by the respondents in this regard and their corresponding frequencies are as follows: bush fires (132/52.0%) and conversion of ecosystem land uses for crop cultivation (112/44.1%).

Isolating and Investigating Updrafts Induced by Wildland Fires Using an Airborne Doppler Lidar During FIREX‐AQ

AbstractUnderstanding the complex dynamical interactions that occur during the evolution of a wildland fire still remains a challenge within the research community. Processes such as entrainment, the incident wind field, the interaction between neighboring updrafts, among other processes, motivates the need for more intensive measurement campaigns to determine the mechanisms responsible for the processes observed as wildland fire updrafts evolve. A recent opportunity to examine processes associated with wildland fires was made possible with a Doppler lidar (DL) mounted on a Twin Otter aircraft to measure horizontal and vertical winds during the 2019 Fire Influence on Regional‐to‐Global Environments and Air Quality campaign. Using the data collected, a technique was developed to isolate updrafts over designated hotspots with the intention of statistically analyzing the updraft samples as well as assessing specific cases that underscore the complex dynamical interactions generated by wildland fire behavior. Strong evidence in support of statistically derived relationships between the updraft characteristics and downdraft extrema at the flanks of updrafts are shown using methods developed herein. In addition to the influence of entrainment/detrainment on the updraft structure are features such as updraft displacement and interacting updrafts that could only be resolved by a high along‐ and cross‐beam resolution DL. Lastly, it was found that a high degree of symmetry between profiles to the left and right of core updrafts was preserved for most of the cases, which validates some of the assumptions typically used in idealized updraft formulations.

Finite element modelling of lattice angle steel structures exposed to wildland fires

Essential civil infrastructure such as transmission line supporting towers and communication base towers that are traditionally formed from lattice angle steel structures are critical global assets, since their development promotes the establishment of electric power supply systems and modern telecommunication networks. Because this infrastructure is commonly located in rural and urban wildland areas, such towers may be prone to wildland fire attack, particularly in the current climate of severe heatwaves and droughts. Accordingly, a comprehensive study of the behaviour and response of lattice angle steel structures under fire loading is needed to assist in structural design to resist fire loading. In this paper, a finite element (FE) model of lattice angle steel structures is constructed using ABAQUS software. Several aspects that include material and geometric non-linearities, load eccentricities on component members, bolted joint slippage, and the use of the explicit dynamic analysis technique for a quasi-static loading procedure, are considered and applied in the FE model. The accuracy and reliability of the FE representation are validated by comparing its predictions with relevant existing experimental results. By incorporating the codified temperature-dependent material properties of structural steel as well as a calibrated load-slip relationship for bolted connections at elevated temperatures, the FE model is extended for performing structural fire analysis. The variations of the steelwork temperatures in wildland fires can be calculated based on representative temperature-time wildland fire curves and is adopted in the fire analysis. By invoking the FE model, an example of lattice angle steel structures is contrived to elucidate the fundamental behaviour of these structures in wildland fires, through both steady and transient state fire analyses. Parametric studies are also undertaken to evaluate the effects of the changes in the wind load direction, bolt pretension and the protection of critical panel sections on the behaviour of lattice structures when exposed to wildland fires.

Wildland fire, air pollution and cardiovascular health: is it time to focus on the microvasculature as a risk assessment tool?

Climate change favors weather conditions conducive to wildland fires. The intensity and frequency of forest fires are increasing, and fire seasons are lengthening. Exposure of human populations to smoke emitted by these fires increases, thereby contributing to airborne pollution through the emission of gas and particulate matter (PM). The adverse health outcomes associated with wildland fire exposure represent an important burden on the economies and health systems of societies. Even though cardiovascular diseases (CVDs) are the main of cause of the global burden of diseases attributable to PM exposure, it remains difficult to show reliable associations between exposure to wildland fire smoke and cardiovascular disease risk in population-based studies. Optimal health requires a resilient and adaptable network of small blood vessels, namely, the microvasculature. Often alterations of this microvasculature precede the occurrence of adverse health outcomes, including CVD. Biomarkers of microvascular health could then represent possible markers for the early detection of poor cardiovascular outcomes. This review aims to synthesize the current literature to gauge whether assessing the microvasculature can better estimate the cardiovascular impact of wildland fires.

Urban Firefighting Drones: Precise Throwing from UAV

In recent years, the use of unmanned aerial vehicles has spread across different fields of the industry due to their ease of deployment and minimal operational risk. Firefighting is a dangerous task for the humans involved, in which the use of UAVs presents itself as a good first-action protocol for a rapid response to an incipient fire because of their safety and speed of action. Current research is mainly focused on wildland fires, but fires in urban environments are barely mentioned in the bibliography. To motivate the research on this topic, ICUAS’22 organized an international competition inspired by this mission, with the challenge of a UAV traversing an area populated by obstacles, finding a target, and precisely throwing a ball to it. For this competition, the Computer Vision and Aerial Robotics (CVAR-UPM) team developed a solution composed of multiple modules and structured by a mission planner. In this paper, we describe our approach and the developed architecture that led us to be awarded the first prize in the competition.

Simulating spatio-temporal dynamics of surface PM2.5 emitted from Alaskan wildfires

Wildfire is a major disturbance agent in Arctic boreal and tundra ecosystems that emits large quantities of atmospheric pollutants, including PM2.5. Under the substantial Arctic warming which is two to three times of global average, wildfire regimes in the high northern latitude regions are expected to intensify. This imposes a considerable threat to the health of the people residing in the Arctic regions. Alaska, as the northernmost state of the US, has a sizable rural population whose access to healthcare is greatly limited by a lack of transportation and telecommunication infrastructure and low accessibility. Unfortunately, there are only a few air quality monitoring stations across the state of Alaska, and the air quality of most remote Alaskan communities is not being systematically monitored, which hinders our understanding of the relationship between wildfire emissions and human health within these communities. Models simulating the dispersion of pollutants emitted by wildfires can be extremely valuable for providing spatially comprehensive air quality estimates in areas such as Alaska where the monitoring station network is sparse. In this study, we established a methodological framework that is based on an integration of the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model, the Wildland Fire Emissions Inventory System (WFEIS), and the Arctic-Boreal Vulnerability Experiment (ABoVE) Wildfire Date of Burning (WDoB) dataset, an Arctic-oriented fire product. Through our framework, daily gridded surface-level PM2.5 concentrations for the entire state of Alaska between 2001 and 2015 for which wildfires are responsible can be estimated. This product reveals the spatio-temporal patterns of the impacts of wildfires on the regional air quality in Alaska, which, in turn, offers a direct line of evidence indicating that wildfire is the dominant driver of PM2.5 concentrations over Alaska during the fire season. Additionally, it provides critical data inputs for research on understanding how wildfires affect human health which creates the basis for the development of effective and efficient mitigation efforts.