Assessing Wildfire Exposure to Communities and Protected Areas in Portugal

During the 2017 wildfire season in Portugal, unprecedented episodes burned 6% of the country’s area and underscored the need for a long-term comprehensive solution to mitigate future wildfire disasters. In this study, we built and calibrated a national-scale fire simulation system including the underlying fuels and weather data and used the system to quantify wildfire exposure to communities and natural areas. We simulated 10,000 fire season replicates under extreme weather to generate 1.6 million large wildfire perimeters and estimate annual burn probability and fire intensity at 100 m pixel resolution. These outputs were used to estimate wildfire exposure to buildings and natural areas. The results showed a fire exposure of 10,394 structures per year and that 30% of communities accounted for 82% of the total. The predicted burned area in natural sites was 18,257 ha yr−1, of which 9.8% was protected land where fuel management is not permitted. The main burn probability hotspots were in central and northern regions. We highlighted vital priorities to safeguard the most vulnerable communities and promote landscape management programs at the national level. The results can be useful to inform Portugal’s new national plan under implementation, where decision-making is based on a probabilistic methodology. The core strategies include protecting people and infrastructure and wildfire management. Finally, we discuss the next steps necessary to improve and operationalize the framework developed here. The wildfire simulation modeling approach presented in this study is extensible to other fire-prone Mediterranean regions where predicting catastrophic fires can help anticipate future disasters.

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Prescribed Burning Reduces Large, High-Intensity Wildfires and Emissions in the Brazilian Savanna

Fire ◽

10.3390/fire4030056 ◽

2021 ◽

Vol 4 (3) ◽

pp. 56

Author(s):

Filippe L.M. Santos ◽

Joana Nogueira ◽

Rodrigo A. F. de Souza ◽

Rodrigo M. Falleiro ◽

Isabel B. Schmidt ◽

...

Keyword(s):

High Intensity ◽

Prescribed Burning ◽

Fire Management ◽

Fire Regime ◽

Scientific Evidence ◽

Brazilian Savanna ◽

Fire Season ◽

Fire Intensity ◽

Burned Area ◽

Fire Policy

Brazil has recently (2014) changed from a zero-fire policy to an Integrated Fire Management (IFM) program with the active use of prescribed burning (PB) in federal Protected Areas (PA) and Indigenous Territories (IT) of the Brazilian savanna (Cerrado). PB is commonly applied in the management of fire-prone ecosystems to mitigate large, high-intensity wildfires, the associated emissions, and high fire suppression costs. However, the effectiveness of such fire management in reducing large wildfires and emissions over Brazil remains mostly unevaluated. Here, we aim to fill the gap in the scientific evidence of the PB benefits by relying on the most up-to-date, satellite-derived fire datasets of burned area (BA), fire size, duration, emissions, and intensity from 2003 to 2018. We focused on two Cerrado ITs with different sizes and hydrological regimes, Xerente and Araguaia, where IFM has been in place since 2015. To understand fire regime dynamics, we divided the study period into three phases according to the prevalent fire policy and the individual fire scars into four size classes. We considered two fire seasons: management fire season (MFS, which goes from rainy to mid-dry season, when PBs are undertaken) and wildfires season (WFS, when PBs are not performed and fires tend to grow out of control). Our results show that the implementation of the IFM program was responsible for a decrease of the areas affected by high fire recurrence in Xerente and Araguaia, when compared with the Zero Fire Phase (2008–2013). In both regions, PB effectively reduced the large wildfires occurrence, the number of medium and large scars, fire intensity, and emissions, changing the prevalent fire season from the WFS to the MFS. Such reductions are significant since WFS causes higher negative impacts on biodiversity conservation and higher greenhouse gas emissions. We conclude that the effect on wildfires can still be reduced if effective fire management policies, including PB, continue to be implemented during the coming decades.

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Varying relationships between fire radiative power and fire size at a global scale

Biogeosciences ◽

10.5194/bg-16-275-2019 ◽

2019 ◽

Vol 16 (2) ◽

pp. 275-288 ◽

Cited By ~ 7

Author(s):

Pierre Laurent ◽

Florent Mouillot ◽

Maria Vanesa Moreno ◽

Chao Yue ◽

Philippe Ciais

Keyword(s):

Patch Size ◽

Empirical Relation ◽

Global Scale ◽

Fire Season ◽

Fire Intensity ◽

Burned Area ◽

Fire Size ◽

Fire Emissions ◽

Radiative Power ◽

Fire Radiative Power

Abstract. Vegetation fires are an important process in the Earth system. Fire intensity locally impacts fuel consumption, damage to the vegetation, chemical composition of fire emissions and also how fires spread across landscapes. It has been observed that fire occurrence, defined as the frequency of active fires detected by the MODIS sensor, is related to intensity with a hump-shaped empirical relation, meaning that occurrence reaches a maximum at intermediate fire intensity. Raw burned area products obtained from remote sensing can not discriminate between ignition and propagation processes. To go beyond burned area and to test if fire size is driven by fire intensity at a global scale as expected from empirical fire spread models, we used the newly delivered global FRY database, which provides fire patch functional traits based on satellite observation, including fire patch size, and the fire radiative power measures from the MCD14ML dataset. This paper describes the varying relationships between fire size and fire radiative power across biomes at a global scale. We show that in most fire regions of the world defined by the GFED database, the linear relationship between fire radiative power and fire patch size saturates for a threshold of intermediate-intensity fires. The value of this threshold differs from one region to another and depends on vegetation type. In the most fire-prone savanna regions, once this threshold is reached, fire size decreases for the most intense fires, which mostly happen in the late fire season. According to the percolation theory, we suggest that the decrease in fire size for more intense late season fires is a consequence of the increasing fragmentation of fuel continuity throughout the fire season and suggest that landscape-scale feedbacks should be developed in global fire modules.

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Varying relationships between fire intensity and fire size at global scale

10.5194/bg-2018-334 ◽

2018 ◽

Author(s):

Pierre Laurent ◽

Florent Mouillot ◽

Maria Vanesa Moreno ◽

Chao Yue ◽

Philippe Ciais

Keyword(s):

Patch Size ◽

Empirical Relation ◽

Satellite Observation ◽

Fire Spread ◽

Global Scale ◽

Fire Season ◽

Fire Intensity ◽

Burned Area ◽

Fire Size ◽

Fire Emissions

Abstract. Vegetation fires are an important process in the Earth system. Fire intensity locally impacts fuel consumption, damage to the vegetation, chemical composition of fire emissions but also how fires spread across landscapes. It has been observed that fire occurrence, defined as the frequency of active fires detected by the MODIS sensor, is related to intensity with a hump-shaped empirical relation meaning that occurrence reaches a maximum at intermediate intensity. Raw burned area products obtained from remote-sensing can not discriminate between ignition and propagation processes. Here we use the newly delivered global FRY database, which provides fire patch functional traits including fire patch size from satellite observation, to go beyond burned area, and to test if fire size is driven by fire intensity at global scale as expected from empirical fire spread models. We show that in most regions of the world the linear relationship between fire intensity and fire patch size saturates for a threshold of intermediate intensity fires. The value of the threshold differs from one region to another, and we suggest that it might be driven by drought, and the amount of available biomass. In some regions, once this threshold is reached, we also observe that fire size decreases for the most intense fires, which mostly happen in the late fire season. According to the percolation theory, we suggest that this effect is a consequence of the increasing fragmentation of fuel continuity along the fire season so that landscape-scale feedbacks should be developed in global fire modules.

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Predicting Fire Season Intensity in Maritime Southeast Asia with Interpretable Models

10.31223/x59320 ◽

2021 ◽

Author(s):

William Daniels ◽

Dorit Hammerling ◽

Rebecca Buchholz ◽

Helen Worden ◽

Fatimah Ahamad

Keyword(s):

Climate Variability ◽

Southeast Asia ◽

Southern Oscillation ◽

Longwave Radiation ◽

Fire Season ◽

Fire Intensity ◽

Climate Index ◽

Burned Area ◽

Lead Times ◽

Modeling Framework

There have been many extreme fire seasons in Maritime Southeast Asia (MSEA) over the last two decades, a trend which will likely continue, if not accelerate, due to climate change. Fires, in turn, are a major driver of atmospheric carbon monoxide (CO) variability, especially in the Southern Hemisphere. Previous studies have explored the relationship between climate variability and fire counts, burned area, and atmospheric CO through regression models that use climate mode indices as predictor variables. Here we model the connections between climate variability and atmospheric CO at a level of complexity not yet studied and make accurate predictions of atmospheric CO (a proxy for fire intensity) at useful lead times. To do this, we develop a regularization-based statistical modeling framework that can accommodate multiple lags of a single climate index, which we show to be an important feature in explaining CO. We use this framework to present advancements over previous modeling efforts, such as the inclusion of outgoing longwave radiation (OLR) anomalies, the use of high resolution weekly data, and a stability analysis that adds weight to the scientific interpretation of selected model terms. We find that the El Nino Southern Oscillation (ENSO), the Dipole Mode Index (DMI), and OLR (as a proxy for the Madden-Julian Oscillation) at various lead times are the most significant predictors of atmospheric CO in MSEA. We further show that the model gives accurate predictions of atmospheric CO at leads times of up to 6 months, making it a useful tool for fire season preparedness.

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AEGIS: a wildfire prevention and management information system

Natural Hazards and Earth System Science ◽

10.5194/nhess-16-643-2016 ◽

2016 ◽

Vol 16 (3) ◽

pp. 643-661 ◽

Cited By ~ 24

Author(s):

Kostas Kalabokidis ◽

Alan Ager ◽

Mark Finney ◽

Nikos Athanasis ◽

Palaiologos Palaiologou ◽

...

Keyword(s):

Fire Hazard ◽

Fire Behavior ◽

End Users ◽

Burned Area ◽

Fire Control ◽

Web Based ◽

Ignition Point ◽

Weather Information ◽

Management Platform ◽

Burn Probability

Abstract. We describe a Web-GIS wildfire prevention and management platform (AEGIS) developed as an integrated and easy-to-use decision support tool to manage wildland fire hazards in Greece (http://aegis.aegean.gr). The AEGIS platform assists with early fire warning, fire planning, fire control and coordination of firefighting forces by providing online access to information that is essential for wildfire management. The system uses a number of spatial and non-spatial data sources to support key system functionalities. Land use/land cover maps were produced by combining field inventory data with high-resolution multispectral satellite images (RapidEye). These data support wildfire simulation tools that allow the users to examine potential fire behavior and hazard with the Minimum Travel Time fire spread algorithm. End-users provide a minimum number of inputs such as fire duration, ignition point and weather information to conduct a fire simulation. AEGIS offers three types of simulations, i.e., single-fire propagation, point-scale calculation of potential fire behavior, and burn probability analysis, similar to the FlamMap fire behavior modeling software. Artificial neural networks (ANNs) were utilized for wildfire ignition risk assessment based on various parameters, training methods, activation functions, pre-processing methods and network structures. The combination of ANNs and expected burned area maps are used to generate integrated output map of fire hazard prediction. The system also incorporates weather information obtained from remote automatic weather stations and weather forecast maps. The system and associated computation algorithms leverage parallel processing techniques (i.e., High Performance Computing and Cloud Computing) that ensure computational power required for real-time application. All AEGIS functionalities are accessible to authorized end-users through a web-based graphical user interface. An innovative smartphone application, AEGIS App, also provides mobile access to the web-based version of the system.

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Twenty-first century droughts have not increasingly exacerbated fire season severity in the Brazilian Amazon

Scientific Reports ◽

10.1038/s41598-021-82158-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

R. Libonati ◽

J. M. C. Pereira ◽

C. C. Da Camara ◽

L. F. Peres ◽

D. Oom ◽

...

Keyword(s):

Forest Fires ◽

Brazilian Amazon ◽

First Century ◽

Fire Season ◽

Fire Intensity ◽

Amazon Forest ◽

Active Fire ◽

Fire Activity ◽

Twenty First Century ◽

In Fire

AbstractBiomass burning in the Brazilian Amazon is modulated by climate factors, such as droughts, and by human factors, such as deforestation, and land management activities. The increase in forest fires during drought years has led to the hypothesis that fire activity decoupled from deforestation during the twenty-first century. However, assessment of the hypothesis relied on an incorrect active fire dataset, which led to an underestimation of the decreasing trend in fire activity and to an inflated rank for year 2015 in terms of active fire counts. The recent correction of that database warrants a reassessment of the relationships between deforestation and fire. Contrasting with earlier findings, we show that the exacerbating effect of drought on fire season severity did not increase from 2003 to 2015 and that the record-breaking dry conditions of 2015 had the least impact on fire season of all twenty-first century severe droughts. Overall, our results for the same period used in the study that originated the fire-deforestation decoupling hypothesis (2003–2015) show that decoupling was clearly weaker than initially proposed. Extension of the study period up to 2019, and novel analysis of trends in fire types and fire intensity strengthened this conclusion. Therefore, the role of deforestation as a driver of fire activity in the region should not be underestimated and must be taken into account when implementing measures to protect the Amazon forest.

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Understanding the Impact of Different Landscape-Level Fuel Management Strategies on Wildfire Hazard in Central Portugal

Forests ◽

10.3390/f12050522 ◽

2021 ◽

Vol 12 (5) ◽

pp. 522

Author(s):

Akli Benali ◽

Ana C. L. Sá ◽

João Pinho ◽

Paulo M. Fernandes ◽

José M. C. Pereira

Keyword(s):

Management Strategies ◽

Treatment Strategies ◽

Fire Season ◽

Burned Area ◽

Treatment Area ◽

Fuel Treatment ◽

The North ◽

Wildfire Hazard ◽

Central Portugal ◽

The Impact

The extreme 2017 fire season in Portugal led to widespread recognition of the need for a paradigm shift in forest and wildfire management. We focused our study on Alvares, a parish in central Portugal located in a fire-prone area, which had 60% of its area burned in 2017. We evaluated how different fuel treatment strategies may reduce wildfire hazard in Alvares through (i) a fuel break network with different extents corresponding to different levels of priority and (ii) random fuel treatments resulting from a potential increase in stand-level management intensity. To assess this, we developed a stochastic wildfire simulation system (FUNC-SIM) that integrates uncertainties in fuel distribution over the landscape. If the landscape remains unchanged, Alvares will have large burn probabilities in the north, northeast and center-east areas of the parish that are very often associated with high fireline intensities. The different fuel treatment scenarios decreased burned area between 12.1–31.2%, resulting from 1–4.6% increases in the annual treatment area and reduced the likelihood of wildfires larger than 5000 ha by 10–40%. On average, simulated burned area decreased 0.22% per each ha treated, and cost-effectiveness decreased with increasing area treated. Overall, both fuel treatment strategies effectively reduced wildfire hazard and should be part of a larger, holistic and integrated plan to reduce the vulnerability of the Alvares parish to wildfires.

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Demographic Effects of Severe Fire in Montane Shrubland on Tasmania’s Central Plateau

Fire ◽

10.3390/fire4030032 ◽

2021 ◽

Vol 4 (3) ◽

pp. 32

Author(s):

Judy A. Foulkes ◽

Lynda D. Prior ◽

Steven W. J. Leonard ◽

David M. J. S. Bowman

Keyword(s):

Woody Species ◽

Fire Frequency ◽

Fire Season ◽

Burned Area ◽

Large Area ◽

Seedling Regeneration ◽

Central Plateau ◽

Conservation Area ◽

Severe Fire ◽

Representative Area

Australian montane sclerophyll shrubland vegetation is widely considered to be resilient to infrequent severe fire, but this may not be the case in Tasmania. Here, we report on the vegetative and seedling regeneration response of a Tasmanian non-coniferous woody montane shrubland following a severe fire, which burned much of the Great Pine Tier in the Central Plateau Conservation Area during the 2018–2019 fire season when a historically anomalously large area was burned in central Tasmania. Our field survey of a representative area burned by severe crown fire revealed that more than 99% of the shrubland plants were top-killed, with only 5% of the burnt plants resprouting one year following the fire. Such a low resprouting rate means the resilience of the shrubland depends on seedling regeneration from aerial and soil seedbanks or colonization from plants outside the burned area. Woody species’ seedling densities were variable but generally low (25 m−2). The low number of resprouters, and reliance on seedlings for recovery, suggest the shrubland may not be as resilient to fire as mainland Australian montane shrubland, particularly given a warming climate and likely increase in fire frequency.

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Using the Landsat Burned Area Products to Derive Fire History Relevant for Fire Management and Conservation in the State of Florida, Southeastern USA

Fire ◽

10.3390/fire4020026 ◽

2021 ◽

Vol 4 (2) ◽

pp. 26

Author(s):

Casey Teske ◽

Melanie K. Vanderhoof ◽

Todd J. Hawbaker ◽

Joe Noble ◽

John Kevin Hiers

Keyword(s):

Prescribed Fire ◽

Spatial Data ◽

Fire History ◽

Fire Management ◽

Fire Behavior ◽

Fire Risk ◽

Behavior Modeling ◽

Burned Area ◽

Burned Areas ◽

Burn Probability

Development of comprehensive spatially explicit fire occurrence data remains one of the most critical needs for fire managers globally, and especially for conservation across the southeastern United States. Not only are many endangered species and ecosystems in that region reliant on frequent fire, but fire risk analysis, prescribed fire planning, and fire behavior modeling are sensitive to fire history due to the long growing season and high vegetation productivity. Spatial data that map burned areas over time provide critical information for evaluating management successes. However, existing fire data have undocumented shortcomings that limit their use when detailing the effectiveness of fire management at state and regional scales. Here, we assessed information in existing fire datasets for Florida and the Landsat Burned Area products based on input from the fire management community. We considered the potential of different datasets to track the spatial extents of fires and derive fire history metrics (e.g., time since last burn, fire frequency, and seasonality). We found that burned areas generated by applying a 90% threshold to the Landsat burn probability product matched patterns recorded and observed by fire managers at three pilot areas. We then created fire history metrics for the entire state from the modified Landsat Burned Area product. Finally, to show their potential application for conservation management, we compared fire history metrics across ownerships for natural pinelands, where prescribed fire is frequently applied. Implications of this effort include increased awareness around conservation and fire management planning efforts and an extension of derivative products regionally or globally.

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Temporal variations and change in forest fire danger in Europe for 1960–2012

Natural Hazards and Earth System Science ◽

10.5194/nhess-14-1477-2014 ◽

2014 ◽

Vol 14 (6) ◽

pp. 1477-1490 ◽

Cited By ~ 39

Author(s):

A. Venäläinen ◽

N. Korhonen ◽

O. Hyvärinen ◽

N. Koutsias ◽

F. Xystrakis ◽

...

Keyword(s):

Forest Fire ◽

Forest Fires ◽

National Level ◽

Temporal Variations ◽

Fire Danger ◽

Fire Season ◽

Fire Weather ◽

Fire Weather Index ◽

Current Season ◽

Forest Fire Danger

Abstract. Understanding how fire weather danger indices changed in the past and how such changes affected forest fire activity is important in a changing climate. We used the Canadian Fire Weather Index (FWI), calculated from two reanalysis data sets, ERA-40 and ERA Interim, to examine the temporal variation of forest fire danger in Europe in 1960–2012. Additionally, we used national forest fire statistics from Greece, Spain and Finland to examine the relationship between fire danger and fires. There is no obvious trend in fire danger for the time period covered by ERA-40 (1960–1999), whereas for the period 1980–2012 covered by ERA Interim, the mean FWI shows an increasing trend for southern and eastern Europe which is significant at the 99% confidence level. The cross correlations calculated at the national level in Greece, Spain and Finland between total area burned and mean FWI of the current season is of the order of 0.6, demonstrating the extent to which the current fire-season weather can explain forest fires. To summarize, fire risk is multifaceted, and while climate is a major determinant, other factors can contribute to it, either positively or negatively.

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