Modelling the long term effect of changes in fire frequency on the total area burnt

Wildfires are one of the major problems in Mediterranean countries, and much effort is done by the governments to dissuade people from starting fires. Public campaigns often promote the idea that the more ignitions the larger the surface burnt will be. This reasoning is, however, not so straightforward. This paper addresses the question of how fire frequency relates to the total area burnt by using a model of fire regime that includes variables such as the number of ignitions, fire fighting capacity, fuel accumulation rates, existence of prescribed burning and meteorological variability. This question was addressed by performing three experimental simulations: effect of the number of potential ignitions, the combined effect of the number of ignitions and extinction capacity, and the non random spatial pattern of fire ignitions. Results showed that a larger number ignitions did not have a great effect on the total area burnt but had an effect in the occurrence of large fires, independently of the extinction capacity and of the spatial distribution of ignitions. An explanation for these findings is provided and management implications of these results are briefly discussed

Assessment of Forest Fire Risk in European Mediterranean Region: Comparison of Satellite-Derived and Meteorological Indices

Forest fires are a major hazard to Mediterranean forests where, on average, half a million hectares of forested areas are burned every year. It is for this reason that the assessment of fire risk lies at the heart of fire prevention policies in the region. Often, the estimation of forest fire risk involves the integration of meteorological and other fuel-related variables leading to an index that assesses the different levels of risk. Two indices that are frequently used to estimate the level of fire risk are the Fire Weather Index (FWI) and the Normalized Difference Vegetation Index (NDVI). Although the correlation between the number of fires and the level of risk determined by the indices has been demonstrated; however the analysis that lead to this conclusion considered only the areas where the fires took place. The present paper analyzes the behaviour of these fire risk indices both in areas where fires took place and in those where fires did not occur. It analyzes and compares the potential of the two indices to discriminate different levels of fire risk over large areas using quantitative and graphical methods. The analysis is performed considering a dataset of 10 years of fire events, satellite data and meteorological data for Spain. The results show a better performance of the FWI over NDVI in identifying areas at risk of fires.JRC.H.7-Land management and natural hazard

Fire behaviour in canyons due to symmetric and asymmetric ignitions

The eruptive propagation of a fire is a particular behaviour characterized by a sudden increase in the rate of spread and intensity without any change in the external driving forces such as wind velocity and ambient temperature, vegetation type and moisture content. It is, therefore, a local or internal dynamic connected with the terrain configuration and the ignition position that regulates fire spreading and causes its acceleration. This phenomenon is particularly evident and common in canyons. This work aims to study the effect ignition position on the fire propagation in a canyon by means of a physically-based computational code. The code WFDS was shown to be effective to describe the fire behaviour throughout such a terrain configuration

Cross-Fire : a grid platform to integrate geo-referenced web services for real-time risk management

Fire propagation simulation tools are useful at different levels of forest fire management. From prescribed fire planning to fuel hazard assessment or to the development of fire suppression strategies on wildfires or even training activities. Nevertheless, real time use of such tools is still very limited among the operational authorities for several reasons: lack of good real time data, lack of training or even lack of confidence on the capabilities of actual systems, among others. Wildfire management is a relevant Civil Protection (CP) activity that involves many different and autonomous actors, from public bodies to research centres and should some how reach the general public as an information and alert system. It requires a fast and reliable risk management support system, with real-time or near real-time availability of critical geo-referenced data and settings-based forecasts for fire spreading. CP applications require a strict integration of human and physical resources that must be shared in a coordinated and effective way and be available for the whole emergency procedure. The GRID and Virtual Organizations (VO) enable such integration by providing the coordination and the sharing of the available interconnected resources (computing, storage, communication, sensors and actuators) geographically scattered across national borders. On the another hand, OGC (Open Geospatial Consortium) based geo-web services are being adopted worldwide, as the technology to support the development of complex distributed applications over grid platforms, to deal with data from many different sources, including meteorological stations and satellites. Recent work clearly showed the advantage of the OGC proposals for open standards for geospatial interchange formats, over past legacy formats and applications.Fundação para a Ciência e a Tecnologia (FCT

Estimation of shub height for fuel-type mapping combining airborne LiDAR and simultaneous color infrared ortho imaging

P. 341-348A fuel-type map of a predominantly shub-land area in central Portugal was generated for a fire research experimental site, by combining airborne light detection and ranging (LiDAR), and simultaneous color infrared ortho imaging. Since the vegetation canopy and the ground are too close together to be easily discerned by LiDAR pulses, standard of processing LiDAR data did not provide an accurate estimate of shrub heightS

Recent Forest Fire Related Accidents in Europe

Forest fires can cause injuries and death to fire fighters and to population affected by them. The analysis of these accidents can provide a better insight about their causes and circumstances and develop guidelines to improve safety of all those at the fire line. These events are also a challenge for researchers as we try to better understand how fire and people behave and with this knowledge contribute to avoid these accidents. Some recent cases involving fatal accidents in five different countries are described and analyzed in this book. Common elements among them are the fact that both several fatalities and fire eruptions occurred in all of them. The number of victims ranges from two in Palasca (France) accident to 27 in Arthemida (Greece) case and they include professional and well experienced fire fighters and members of the population, in some cases even children. May these cases be a reminder that every person can be endangered by forest fires and a call to enforce the common goal of preventing them.JRC.H.7-Land management and natural hazard

Defining extreme wildfire events: difficulties, challenges, and impacts

Every year worldwide some extraordinary wildfires occur, overwhelming suppressioncapabilities, causing substantial damages, and often resulting in fatalities. Given their increasingfrequency, there is a debate about how to address these wildfires with significant social impacts,but there is no agreement upon terminology to describe them. The concept of extreme wildfire event(EWE) has emerged to bring some coherence on this kind of events. It is increasingly used, often asa synonym of other terms related to wildfires of high intensity and size, but its definition remainselusive. The goal of this paper is to go beyond drawing on distinct disciplinary perspectives todevelop a holistic view of EWE as a social-ecological phenomenon. Based on literature review andusing a transdisciplinary approach, this paper proposes a definition of EWE as a process and anoutcome. Considering the lack of a consistent scale of gravity to leverage extreme wildfire eventssuch as in natural hazards (e.g., tornados, hurricanes and earthquakes) we present a proposal ofwildfire classification with seven categories based on measurable fire spread and behavior parametersand suppression difficulty. The categories 5 to 7 are labeled as EWE