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To assess wildfire risk linked to lightning-caused wildfires, the present study tests the spatial- and temporal-scale distribution variability of lightning fires in Western Canada between 1981 and 2018. We examined clustering, trends, distances between clusters, and the fire season. For this study, the nearest neighbours, K-function, Moran's I, Mann-Kendall, and the Getis-ord Gi* statistics were used. These statistics were visualized by a Space Time Cube model with a hexagon grid. Lightning- ignited wildfires cluster spatially up to 270 km with an observed overall nonsignificant decreasing trend for the number of fires. Overall, northeastern Alberta, central Saskatchewan, and southeastern British Columbia show clustering of lightning fires. In June, there is significant clustering in northwestern and eastern Alberta, while in July fires cluster in northeastern Alberta and in southeastern British Columbia. In August, fire clusters occurred only in southeastern and south-central British Columbia. These results highlight regions that are experiencing persistent lightning fire clustering activity. This provides a focal point to assess wildfire risk to communities and values at risk, while informing local and regional management agencies in preparedness, resource capacity management, and detection. Additionally, it provides a baseline for future research into biophysical modelling of wildfire initiations. Key words: lightning fires, spatial statistics, temporal patterns, Canada, wildfire, number of fires Pour evaluer le risque d'incendie de foret lie aux feux de foret provoques par la foudre, la presente etude teste la variability de la distribution a l'echelle spatiale et temporelle des feux de foudre dans l'ouest du Canada entre 1981 et 2018. Nous avons examine les regroupements, les tendances, les distances entre les regroupements et la saison des feux. Pour cette etude, les statistiques des plus proches voisins, de la fonction K, du I de Moran, de Mann-Kendall et du Getis-ord Gi* ont ete utilisees. Ces statistiques ont ete visualisees par un modele Space Time Cube avec une grille hexagonale. Les incendies de foret declenches par la foudre se regroupent dans l'espace jusqu'a 270 km avec une tendance generale non significative a la baisse du nombre d'incendies. Dans l'ensemble, le nord-est de l'Alberta, le centre de la Saskatchewan et le sud-est de la Colombie- Britannique presentent des regroupements de feux provoques par la foudre. En juin, on observe un regroupement significatif dans le nord-ouest et l'est de l'Alberta, tandis qu'en juillet, les feux se regroupent dans le nord-est de l'Alberta et dans le sud-est de la Colombie-Britannique. En aout, les regroupements de feux ne se sont produits que dans le sud-est et le centre-sud de la Colombie-Britannique. Ces resultats mettent en evidence les regions qui connaissent une activite persistante de regroupement des feux de foudre. Cela fournit un point focal pour evaluer le risque d'incendie de foret pour les communautes et les valeurs a risque, tout en informant les agences de gestion locales et regionales en matiere de preparation, de gestion de la capacite des ressources et de detection. De plus, cela fournit une base de reference pour les recherches futures sur la modelisation biophysique des debuts d'incendies de foret. Mots-cles : incendies provoques par la foudre, statistiques spatiales, modeles temporels, Canada, feux de foret, Introduction Wildfires have the potential to be an integral ecological disturbance within biological communities (Rowe 1983); this can be a result from either human-induced fire or from an environmental interaction [...]

Alberta wildfires vary greatly in severity, resulting in a mosaic of burnt, partially burnt, and unburnt forest. These unburnt patches (refugia) within the fire perimeter are critical for the survival of organisms during the fire and the regeneration process. We examined the literature to identify how the fire regimes and landscape features found in Alberta affect the creation and persistence of refugia, the role of refugia for the flora and fauna of Alberta, how climate change is likely to affect refugia, how humans may alter the creation and effectiveness of refugia, and management implications moving forward. Refugia can vary in scale from small areas of unburnt soil or boulders (centimetres to a few metres), to large stands of unburnt trees (many hectares) with different taxa using these refugia across all the spatial scales. Species reliant on habitat connectivity or old growth forest also benefit from refugia as they can use them as stepping-stones between intact habitats or as a lifeboat to recolonize from. The factors influencing what areas remain unburnt are complex and poorly understood but are likely tied to topography, aspect, proximity to waterbodies, weather changes (precipitation and wind direction), time of day during burning, and vegetation type. Areas with the right combination of topography, aspect, and proximity to water have cooler microclimates and higher moisture than the surrounding areas and may remain unburnt throughout multiple fire events, making them persistent refugia. Other areas may remain unburnt by a chance result of weather changes or having the fire pass through at night, making them random refugia. Many of the features that make persistent refugia unlikely to burn (cooler microclimate and higher moisture) will also buffer the effects of climate change. As a result, it is essential we manage the landscape in such a way as to protect areas that act as persistent refugia from industrial activities. In addition, we must restore fire in the landscape to maintain the mosaic of forest caused by mixed-severity fire, especially in the face of climate change, which is projected to increase the severity and frequency of wildfires in Alberta. Key words: refugia, remnant, unburnt, wildfire, legacies Les incendies de forêt en Alberta varient grandement en gravité, ce qui donne lieu àune mosaïque de forêts brûlées, partiellement brûlées et non brûlées. Ces îlots non brûlés, ou refuges, situés dans le périmètre du feu, sont essentiels àla survie des organismes pendant le feu et au processus de régénération. Les auteurs ont examiné la littérature afin de déterminer comment les régimes de feu et les caractéristiques du paysage en Alberta influencent la création et la persistance de refuges, le rôle des refuges pour la flore et la faune en Alberta, comment les changements climatiques sont susceptibles d'affecter les refuges, comment les humains peuvent modifier la création et l'efficacité des refuges, et les implications de gestion pour l'avenir. L'échelle des refuges peut varier de petites zones de sol ou de blocs rocheux non brûlés (de quelques centimètres àquelques mètres) àde grands peuplements d'arbres non brûlés (plusieurs hectares), différents taxons utilisant ces refuges àtoutes les échelles spatiales. Les espèces qui dépendent de la connectivité des habitats ou des forêts anciennes bénéficient également des refuges, car elles peuvent les utiliser comme étapes entre des habitats intacts ou comme canots de sauvetage pour se recoloniser. Les facteurs qui déterminent les zones qui restent non brûlées sont complexes et mal compris, mais sont probablement liés àla topographie, àl'aspect, àla proximité des cours d'eau, aux changements météorologiques (précipitations et direction du vent), àl'heure de la journée pendant le brûlage et au type de végétation. Les zones présentant la bonne combinaison de topographie, d'aspect et de proximité de l'eau ont des microclimats plus frais et une humidité plus élevée que la zone environnante et peuvent rester non brûlées pendant de multiples incendies, ce qui en fait des refuges persistants. D'autres zones peuvent rester non brûlées par le hasard des changements météorologiques ou du passage du feu la nuit, ce qui en fait des refuges aléatoires. Bon nombre des caractéristiques qui rendent les refuges persistants peu susceptibles de brûler (microclimat plus frais et humidité plus élevée) les aideront également àamortir les effets des changements climatiques. Par conséquent, il est essentiel que nous gérions le paysage de manière àprotéger les zones qui agissent comme des refuges persistants des activités industrielles. En outre, nous devons rétablir le feu dans le paysage afin de maintenir la mosaïque de forêts causée par les feux de gravité mixte, surtout face aux changements climatiques qui devraient accroître la gravité et la fréquence des feux en Alberta. Mots-clés : refuges, vestiges, non brûlés, incendies de forêt, héritages, Introduction Forests throughout Alberta experience wildfire as a naturally occurring disturbance that has dominated and molded the landscape over time. However, the relationship between fire and the landscape is highly [...]

Background. Fire weather indices forecast fire behaviour and provide valuable information for wildland fire prevention, preparedness, and suppression. However, these indices do not directly account for atmospheric conditions aloft. The province of Alberta, Canada has experienced extreme fire weather conditions during spring for decades, leading to the continued occurrence of disastrous wildland fires. Aims. We examined the Hot-Dry-Windy Index (HDWI) and spread days over the first 4 days of 80 large wildland fires that started in May 1990--2019 in Alberta. Methods. HDWI values were calculated using ERA5 reanalysis data from the 1000, 975 and 950 hPa levels. Differences between HDWI distributions on spread days and non-spread days were examined using permutation tests. Initial Spread Index was also examined as it is considered an important Fire Weather Index System value for wildland fire spread during spring in Alberta. Key results. Higher median HDWI values were observed on spread days than non-spread days, where median Initial Spread Index values showed little to no difference. Conclusions. This analysis suggests that HDWI can contribute to the prediction of significant spring wildland fire spread in Alberta. Implications. Forecasted HDWI and HDWI climatologies may provide additional decision support for wildland fire management agencies. [ABSTRACT FROM AUTHOR]

We celebrate the 50th anniversary of the Canadian Journal of Forest Research by reflecting on the considerable progress accomplished in select areas of Canadian wildland fire science over the past half century. Specifically, we discuss key developments and contributions in the creation of the Canadian Forest Fire Danger Rating System; the relationships between wildland fire and weather, climate, and climate change; fire ecology; operational decision support; and wildland fire management. We also discuss the evolution of wildland fire management in Banff National Park as a case study. We conclude by discussing some possible directions in future Canadian wildland fire research including the further evaluation of fire severity measurements and effects; the efficacy of fuel management treatments; climate change effects and mitigation; further refinement of models pertaining to fire risk analysis, fire behaviour, and fire weather; and the integration of forest management and ecological restoration with wildland fire risk reduction. Throughout the paper, we reference many contributions published in the Canadian Journal of Forest Research, which has been at the forefront of international wildland fire science. Key words: Banff National Park, Canadian Forest Fire Danger Rating System, fire ecology, wildland fire, wildfire. La science des incendies forestiers a connu des progres considerables au cours du dernier demi-siecle, avec des avancees dans tous les principaux domaines d'investigation. Dans cet article, nous celebrons le 50e anniversaire de la Revue canadienne de recherche forestiere en reflechissant a l'histoire de la recherche scientifique sur les incendies de foret au Canada. Nous examinons l'evolution de cette science au cours des 50 dernieres annees au Canada, notamment pour les principaux developpements et contributions dans la conception de la Methode canadienne d'evaluation des dangers d'incendie de foret, la climatologie-meteorologie des incendies, le changement climatique, l'ecologie des incendies et la gestion operationnelle des incendies. Nous presentons, a titre d'exemple, une etude de cas sur l'evolution de la gestion des incendies dans le parc national Banff. Nous concluons en discutant des orientations des recherches futures sur les incendies de foret au Canada, notamment pour ce qui est de l'evaluation future de la gravite des incendies et de leurs effets, de l'efficacite des traitements de gestion des combustibles et des effets et de l'attenuation du changement climatique, ainsi que du developpement de l'analyse des risques d'incendie de meme que des modeles de comportement des incendies. Nous constatons egalement qu'il est toujours necessaire de mieux integrer la gestion des forets et la restauration ecologique a la reduction des risques d'incendie. Tout au long de l'article, nous faisons reference aux nombreuses contributions publiees dans la Revue canadienne de recherche forestiere, qui a ete a la pointe de la science internationale en matiere d'incendies de foret. Mots-cles : parc national Banff, Methode canadienne d'evaluation des dangers d'incendie de foret, ecologie de feu, feux de forets., Introduction Wildland fire has been a persistent feature of the Canadian landscape for millennia (Richard 1993; Price et al. 2013). On average, fires have burned 1.96 Mha per year in [...]

Recently, the World Scientists' Warning to Humanity: a Second Notice was issued in response to ongoing and largely unabated environmental degradation due to anthropogenic activities. In the warning, humanity is urged to practice more environmentally sustainable alternatives to business as usual to avoid potentially catastrophic outcomes. Following the success of their warning, the Alliance of World Scientists called for discipline-specific follow-up papers. This paper is an answer to that call for the topic of wildland fire. Across much of Canada and the world, wildfires are anticipated to increase in severity and frequency in response to anthropogenic activities. The world scientists' second warning provides the opportunity for wildland fire researchers to raise the profile of the potential impacts that anthropogenic activities are likely to have on future fire regimes and, in return, what impacts future fire regimes may have on humanity. We discuss how wildfire is related to several issues of concern raised in the world scientists' second warning, including climate change, human population growth, biodiversity and forests, and freshwater availability. Furthermore, we touch on the potential future health impacts and challenges to wildfire suppression and management in Canada. In essence, our wildfire scientists' warning to humanity is that we, as a society, will have to learn to live with more fire on the landscape. We provide some recommendations on how we might move forward to prepare for and adapt to future wildfire regimes in Canada. Although this paper is primarily Canadian in focus, the concepts and information herein also draw from international examples and are of relevance globally. Key words: climate change, wildfire, wildland fire, world scientists' warning. Recemment, le << World Scientists' Warning to Humanity : a Second Notice >> a ete publie en reaction a la degradation de l'environnement qui se poursuit quasiment sans relache a cause de l'activite humaine. Dans cette mise en garde, l'humanite est instamment priee d'adopter des pratiques alternatives plus durables du point de vue environnemental que les pratiques actuelles pour eviter des consequences potentiellement catastrophiques. Etant donnee le succes de leur mise en garde, le << Alliance of World Scientists >> a lance un appel a contribution en sollicitant des articles de suivi disciplinaires. Cet article constitue une reponse a cet appel a contribution pour le domaine des feux de foret. Dans la majeure partie du Canada, et du monde, on prevoit que la severite et la frequence des feux de foret ira en augmentant a cause de l'activite humaine. Le deuxieme avertissement des scientifiques du monde fournit l'occasion aux chercheurs dans le domaine des feux de foret de mieux faire connaitre les impacts que l'activite humaine pourrait vraisemblablement avoir sur les futurs regimes des feux et, en retour, quels impacts les futurs regimes des feux pourraient avoir sur l'humanite. Nous discutons de la facon dont les feux de foret sont relies a plusieurs sujets de preoccupation souleves par la deuxieme mise en garde des scientifiques a travers le monde, incluant les changements climatiques, la croissance de la population humaine, la biodiversite et les forets ainsi que la disponibilite de l'eau douce. De plus, nous abordons les impacts sur la sante et les defis potentiels a venir poses par la gestion et la suppression des feux de foret. Essentiellement, notre mise en garde pour l'humanite en tant que specialistes des feux de foret est que nous aurons, comme societe, a apprendre a vivre avec plus de feux dans le paysage. Nous formulons certaines recommandations sur la fa^on dont nous pourrions aller de l'avant pour se preparer et s'adapter aux futurs regimes des feux au Canada. Bien que principalement axes sur le Canada, les concepts et l'information presentes dans cet article s'inspirent aussi d'exemples internationaux et sont pertinents a l'echelle mondiale. [Traduit par la Redaction] Mots-cles: changement climatique, feu de foret, feu de vegetation, avertissement des scientifiques a travers le monde., 1. Introduction In 1992, the Union of Concerned Scientists (1992) along with more than 1700 independent scientists drafted and signed the World Scientists' Warning to Humanity, which pleaded with people [...]

Contemporary fire regimes of Canadian forests have been well documented based on forest fire records between the late 1950s to 1990s. Due to known limitations of fire datasets, an analysis of changes in fire-regime characteristics could not be easily undertaken. This paper presents fire-regime trends nationally and within two zonation systems, the homogeneous fire-regime zones and ecozones, for two time periods, 1959-2015 and 1980-2015. Nationally, trends in both area burned and number of large fires ([greater than or equal to]200 ha) have increased significantly since 1959, which might be due to increases in lightning-caused fires. Human-caused fires, in contrast, have shown a decline. Results suggest that large fires have been getting larger over the last 57 years and that the fire season has been starting approximately one week earlier and ending one week later. At the regional level, trends in fire regimes are variable across the country, with fewer significant trends. Area burned, number of large fires, and lightning-caused fires are increasing in most of western Canada, whereas human-caused fires are either stable or declining throughout the country. Overall, Canadian forests appear to have been engaged in a trajectory towards more active fire regimes over the last half century. Key words: fire regime, wildfire, trend analysis, Canadian forests. Les regimes contemporains des feux dans les forets canadiennes ont ete bien documentes selon les archives portant sur les feux de foret, accumulees depuis la fin des annees 1950 jusqu'aux annees 1990. A cause des limitations connues des jeux de donnees sur les feux, on ne pouvait facilement entreprendre une analyse des changements survenus dans les caracteristiques des regimes des feux. Cet article presente l'evolution des regimes des feux a l'echelle nationale et a l'interieur de deux systemes de zonage, la zone ou les regimes des feux sont homogenes et les ecozones, pour deux periodes, soit de 1959 a 2015 et de 1980 a 2015. A l'echelle nationale, dans les deux zones, les superficies brnlees et le nombre de grands feux ([greater than or equal to]200 ha) ont significativement augmente depuis 1959, ce qui pourrait etre du a une augmentation des feux causes par la foudre. Par contre, les feux d'origine humaine ont diminue. Les resultats indiquent que la taille des grands feux a augmente au cours des 57 dernieres annees et que la saison des feux debute environ une semaine plus tot et se termine une semaine plus tard. A l'echelle regionale, l'evolution des regimes des feux varie d'un endroit a l'autre et on observe moins de tendances significatives. Les superficies brUlees, le nombre de grands feux et les feux causes par la foudre sont en augmentation presque partout dans l'ouest du Canada, tandis que les feux d'origine humaine sont soit stables ou en diminution partout dans le pays. Dans l'ensemble, les forets canadiennes semblent engagees sur une trajectoire vers des regimes des feux plus actifs au cours des 50 dernieres annees. [Traduit par la Redaction] Mots-cles : regime des feux, feu de foret, analyse des tendances, forets canadiennes., 1. Introduction The fire-regime concept is composed of fire-related characteristics that describe the occurrence and impact of fires over space and time. In Canada, the fire regime is commonly characterized [...]

Communities interspersed throughout the Canadian wildland are threatened by fires that have become bigger and more frequent in some parts of the country in recent decades. Identifying the fireshed (source area) and pathways from which wildland fire may ignite and spread from the landscape to a community is crucial for risk‐reduction strategy and planning. We used outputs from a fire simulation model, including fire polygons and rate of spread, to map firesheds, fire pathways and corridors and spread distances for 1980 communities in the forested areas of Canada. We found fireshed sizes are larger in the north, where the mean distances between ecumene and fireshed perimeters were greater than 10 km. The Rayleigh Z test indicated that simulated fires around a large proportion of communities show significant directional trends, and these trends are stronger in the Boreal Plains and Shields than in the Rocky Mountain area. The average distance from which fire, when spreading at the maximum simulated rate, could reach the community perimeter was approximately 5, 12 and 18 km in 1, 2 and 3 days, respectively. The average daily spread distances increased latitudinally, from south to north. Spread distances were the shortest in the Pacific Maritime, Atlantic Maritime and Boreal Plains Ecozones, implying lower rates of spread compared to the rest of the country. The fire corridors generated from random ignitions and from ignitions predicted from local fire history differ, indicating that factors other than fuel (e.g. fire weather, ignition pattern) play a significant role in determining the direction that fires burn into a community. [ABSTRACT FROM AUTHOR]

Wildfires burn an average of 2 million hectares per year in Canada, most of which can be attributed to only a few days of severe fire weather. These 'spread days' are often associated with large-scale weather systems. We used extreme threshold values of three Canadian Fire Weather Index System (CFWIS) variables--the fine fuel moisture code (FFMC), initial spread index (ISI), and fire weather index (FWI)--as a proxy for spread days. Then we used self-organizing maps (SOMs) to predict spread days, with sea-level pressure and 500 hPa geopotential height as predictors. SOMs require many input parameters, and we performed an experiment to optimize six key parameters. For each month of the fire season (May-August), we also tested whether SOMs performed better when trained with only one month or with neighbouring months as well. Good performance (AUC of 0.8) was achieved for FFMC and ISI, while nearly good performance was achieved for FWI. To our knowledge, this is the first study to develop a machine-learning model for extreme fire weather that could be deployed in real time. Key words: wildland fire, fire danger, fire regimes, SOM, weather. Les feux, dont la plupart peuvent etre imputes a seulement quelques jours durant lesquels les conditions meteorologiques sont propices aux incendies forestiers severes, detruisent en moyenne deux millions d'hectares de foret par annee au Canada. Ces jours propices a la propagation des feux sont souvent associes a de vastes systemes meteorologiques. Nous avons utilise des valeurs seuils extremes pour trois variables de la methode canadienne de l'indice foret-meteo (MCIFM): l'indice du combustible leger (ICL), l'indice de propagation initiale (IPI) et l'indice foret-meteo (IFM) en tant que substituts pour les jours propices a la propagation des feux. Ensuite, nous avons utilise des cartes autoorganisables (SOM) pour predire les jours propices a la propagation des feux avec comme predicteurs la pression au niveau de la mer et une hauteur du geopotentiel de 500 hPa. Les SOM exigent plusieurs parametres d'entree et nous avons effectue une experience pour optimiser six parametres cles. Pour chaque mois de la saison des feux (mai-aout), nous avons aussi teste si les SOM etaient plus performantes lorsqu'elles etaient entrainees avec seulement un mois ou en incluant aussi les mois voisins. Une bonne performance (AUC de 0,8) a ete obtenue pour ICL et IPI, alors qu'une performance satisfaisante a ete obtenue pour IFM. A notre connaissance, il s'agit de la premiere etude qui elabore un modele d'apprentissage automatique pour des conditions meteorologiques extremes propices aux incendies forestiers qui peut etre deploye en temps reel. [Traduit par la Redaction] Mots-cles: feux de foret, danger d'incendie, regime des feux, cartes autoorganisables (SOM), conditions meteorologiques., 1. Introduction Canada experiences an average of 8000 wildfires per year, burning approximately 2 million hectares (Flannigan et al. 2009). Most of this area is burned by relatively few large [...]

Although broadleaf tree species of the boreal biome have a lower flammability compared to conifers, there is a period following snow melt and prior to leaf flush (i.e., greenup), termed the "spring window" by fire managers, when these forests are relatively conducive to wildfire ignition and spread. The goal of this study was to characterize the duration, timing, and fire proneness of the spring window across boreal Canada and assess the link between these phenological variables and the incidence of springtime wildfires. We used remotely sensed snow cover and greenup data to identify the annual spring window for five boreal ecozones from 2001 to 2021 and then compared seasonality of wildfire starts (by cause) and fire‐conducive weather in relation to this window, averaged over the 21‐year period. We conducted a path analysis to concomitantly evaluate the influence of the spring window's duration, the timing of greenup, and fire‐conducive weather on the annual number and the seasonality of spring wildfires. Results show that the characteristics of spring windows vary substantially from year to year and among geographic zones, with the interior west of Canada having the longest and most fire‐conducive spread window and, accordingly, the greatest springtime wildfire activity. We also provide support for the belief that springtime weather generally promotes wind‐driven, rather than drought‐driven wildfires. The path analyses show idiosyncratic behavior among ecozones, but, in general, the seasonality of the wildfire season is mainly driven by the timing of the greenup, whereas the number of spring wildfires mostly responds to the duration of the spring window and the frequency of fire‐conducive weather. The results of this study allows us to better understand and anticipate the biome‐wide changes projected for the northern forests of North America. [ABSTRACT FROM AUTHOR]

The main objective of this paper is to evaluate whether future climate change would trigger an increase in the fire activity of the Waswanipi area, central Quebec. First, we used regression analyses to model the historical (1973-2002) link between weather conditions and fire activity. Then, we calculated Fire Weather Index system components using 1961-2100 daily weather variables from the Canadian Regional Climate Model for the A2 climate change scenario. We tested linear trends in 1961-2100 fire activity and calculated rates of change in fire activity between 1975-2005, 2030-2060, and 2070-2100. Our results suggest that the August fire risk would double (+110%) for 2100, while the May fire risk would slightly decrease (-20%), moving the fire season peak later in the season. Future climate change would trigger weather conditions more favourable to forest fires and a slight increase in regional fire activity (+7%). While considering this long-term increase, interannual variations of fire activity remain a major challenge for the development of sustainable forest management. Resume: Le principal objectif de cet article est d'evaluer si les changements climatiques futurs vont conduire a une augmentation de l'activite des feux dans la region de Waswanipi, dans le centre du Quebec. Tout d'abord, nous avons utilise des regressions lineaires pour modeliser la relation historique (1973-2002) entre les conditions meteorologiques et l'activite des feux. Ensuite, nous avons calcule les composantes du systeme de l'Indice Fore-Meteo a partir des simulations quotidiennes des conditions meteorologiques du Modele Regional Canadien du Climat pour le scenario A2 de changements climatiques (1961-2100). Nous avons teste les tendances lineaires de l'activite des feux sur la periode 1961-2100, et calcule les taux de changement entre 1975-2005, 2030-2060, et 2070-2100. Nos resultats suggerent que le risque de feu du mois d'aout pourrait doubler (+110 %) d'ici 2100 alors que celui du mois de mai pourrait diminuer (-20 %). Ainsi, le pic saisonnier de l'activite des feux pourrait survenir plus tard dans la saison. Les changements climatiques futurs pourraient egalement creer des conditions plus favorables aux incendies forestiers, et donc a une legere augmentation de l'activite regionale des feux (+7 %). Bien que nos resultats suggerent une augmentation a long terme de l'activite des feux, la variabilite interannuelle des feux demeure un defi important pour le developpement d'un amenagement forestier durable., Introduction In boreal forests, fire is one of the main ecological processes shaping the forest mosaic. In return, regional fire regimes are influenced by forest structure and composition, topography, human [...]