By Domingos Xavier Viegas1, Christoph Aubrecht2,3, Sergio Freire4
1 University of Coimbra, Department of Mechanical Engineering
2 AIT Austrian Institute of Technology, Energy Department
3 The World Bank, LAC Urban and Disaster Risk Management
4 European Commission – Joint Research Centre (JRC), Institute for the Protection and Security of the Citizen
The severity of the 2012 fire season in Europe was well above the average of the last 20 years, according to records of the European Forest Fire Information System (EFFIS) (JRC, 2013). At least for parts of the Mediterranean region, that situation seems to have become even worse in 2013. Particularly in Portugal, the 2013 fire season will be remembered as one of the worst since 1940, the year when the Portuguese authorities began compiling detailed records on fire occurrence (historical data on fire occurrence including burnt area and average fire size dating back until 1980 are available through the EFFIS Fire History application). In order to illustrate this year’s strong fire season and to show how fire hazard is threatening many parts of the world on a recurrent basis, some details are provided here on recent fire occurrence in Portugal.
Winter and early spring were characterized by above-average rainfall responsible for the development of herbaceous and shrub vegetation. From July to mid-September, persistent warm weather dried this vegetation that therefore became susceptible to feed the fire. To worsen the situation, strong east winds were registered frequently. These climatic and meteorological conditions were favorable to fire occurrence and growth, so a large number of intense fires occurred – as many as 300 blazes a day (EC, 2013) – making firefighting activities particularly difficult and dangerous (Figure 1).
Forest fires are recognized as being hazardous to social systems but they should not necessarily constitute events where persons could be hurt or killed. Unfortunately in 2013, in Portugal, some groups of firefighters where surrounded by fire, leaving them without a chance to escape, mostly due to fast fire propagation, together with some tiredness and situational unawareness. The situation resembled a tragic incident in the U.S. state of Arizona this summer recently reported in Earthzine (Davidson, 2013) in which 19 experienced firefighters were killed. In Portugal, a large number of incidences in which personnel and vehicles were put in danger were observed, including six accidents in which nine people lost their lives by the direct action of fire.
In spite of extensive campaigns and constant warnings to the population, a large number of fire ignitions were observed almost every day during the period. On several days, firefighters had to face some 300 or more new ignitions, besides other ongoing fires. As a result, the fire protection system was overwhelmed. On some days, external assistance in the form of aircraft and helicopters was provided to Portugal by other European Union countries (EC, 2013). The accumulated burnt area is on the order of 138,000 hectares.
Since satellite remote sensing of fires started in the 1970s, it has become increasingly important for fire monitoring, particularly in the context of mitigating social impacts. Various sensors using different technologies have been used successfully to detect active fires, as highlighted by some of the contributions to this quarter’s Earthzine Wildfires Theme. Probably the most prominent sensor in that context is MODIS (Moderate Resolution Imaging Spectroradiometer) (Justice et al., 2011) whose data and derived products are provided through NASA’s Rapid Response initiative and the Fire Information for Resource Management System (FIRMS).
Furthermore, data from AVHRR (Advanced Very High Resolution Radiometer) have been applied for fire identification as well as nighttime imagery from DMSP-OLS (Defense Meteorological Satellite Program, Operational Linescan System) (Elvidge et al., 2001). Referring to the above-mentioned persisting dry conditions, satellite-derived soil moisture information has been used in the context of fire research in an attempt to identify increased pre-event vulnerabilities (Aubrecht et al., 2011).
In addition to publicly accessible dedicated fire-specific data portals and initiatives as mentioned above, the International Charter Space and Major Disasters can serve as a means to access Earth Observation data on fire hazard, with most of the major global providers of satellite imagery being active members. The Charter aims to provide a unified system of space data acquisition and delivery to countries and regions affected by any natural or man-made disaster. In 2013, the Charter has been activated twice for large-scale wildfire incidents in Argentina and Australia.
During the 2013 fire season in Portugal, remotely sensed data were extensively used by operational agencies to monitor the risk of fire and to anticipate the days of extreme fire danger in some regions. In several fires that lasted for several days, satellite images were used to assess the evolution of the fire (Figure 2). After the fires, high-resolution satellite images were used to evaluate the impact of these fires and to establish the measures that have to be taken to avoid further damage to the environment. The research team of the first author (Domingos Xavier Viegas) was requested by the Portuguese government to produce a full report on two of the major fires and on the fatal accidents of 2013. Detailed analysis of the situation and a lesson-learning process also is being developed involving the scientific community. Considering political and financial constraints, we can however only hope that better solutions and more will to put them into practice will be established in the near future.
For all the recent progress in Earth Observation technologies (some highlighted in Earthzine’s Wildfires Theme), wildfires remain a serious problem that poses ever-increasing challenges to our ingenuity. Minimizing their often-dramatic environmental and human impacts will require a smart combination of technology, political decision, and willingness to accept changes in our own individual and collective options as societies. May we know how to make the right choices.
Domingos Xavier Viegas is a full professor at the Department of Mechanical Engineering of the University of Coimbra, Portugal. He is president of the Associação para o Desenvolvimento da Aerodinâmica Industrial (ADAI) and head of its research unit on Forest Fires since 1986. He has developed his research activity mainly in the field of forest fire propagation.
Christoph Aubrecht is affiliated with the AIT Austrian Institute of Technology and with the World Bank’s Urban and Disaster Risk Management (DRM) team. He previously provided consultancy to the Global Facility for Disaster Reduction and Recovery (GFDRR) and was visiting scientist at the National Oceanic and Atmospheric Administration’s (NOAA) National Geophysical Data Center (NGDC), Columbia University’s Center for International Earth Science Information Network (CIESIN) and the University of Southern California. His research interests include multi-dimensional spatio-temporal modeling as well as exposure and vulnerability issues in DRM. His recent project work also has focused on determining factors of environmental fire susceptibility based on satellite-derived soil moisture data. He serves as senior adviser to Earthzine.
Sérgio Freire is a geographer who has been researching spatio-temporal human exposure to hazards, and was previously involved in developing integrated forest fire risk methods using satellite imagery and other spatial data. His current work at the Global Security and Crisis Management Unit of the Joint Research Centre (European Commission) focuses on Geographic Information System (GIS) modeling for disaster exposure, risk, and vulnerability analysis at the global level.
The authors wish to thank Luis Mário Ribeiro, from ADAI (Associação para o Desenvolvimento da Aerodinâmica Industrial), for preparation of figure 2 and the European Commission’s Joint Research Centre (JRC) for providing the underlying data.
Aubrecht, C., C.D. Elvidge, K. Baugh, S. Hahn, 2011. Identification of wildfire precursor conditions: Linking satellite based fire and soil moisture data. In: Tavares, J.M.R.S., Natal Jorge, R.M., eds., Computational Vision and Medical Image Processing: VipIMAGE 2011, Leiden: CRC Press/Balkema (Taylor & Francis Group), 347-353.
Davidson, O.G., 2013. Maps of a Wildfire Tragedy Show Why Escape Was Impossible. Earthzine, Theme Issue on ‘Wildfires – From Risk Assessment to Recovery’. Publication date: 10/21/2013.
EC, 2013. EU Civil Protection Mechanism supports Portugal in fighting forest fires. European Commission – Press release IP/13/806. Brussels, 31 August 2013.
Elvidge, C.D., I. Nelson, V.R. Hobson, J. Safran, K. E. Baugh, 2001. Detection of fires at night using DMSP-OLS data. In: Ahern, F.J., Goldammer, J.G., Justice, C.O., eds., Global and Regional Vegetation Fire Monitoring from Space: Planning a Coordinated International Effort, The Hague: SPB Academic Publishing, 125-144.
Freire, S., C. Aubrecht, D.X. Viegas (Eds.), 2013. Wildfires – From Risk Assessment to Recovery. Earthzine, Theme Issue 6(3), 14 articles. Publication date: Third quarter 2013.
JRC, 2013. Forest Fires in Europe, Middle East and North Africa 2012. JRC Technical Reports, EUR 26048 EN. Ispra, Italy: European Commission, Joint Research Centre, Institute for Environment and Sustainability, 108 pp.
Justice, C.O., L. Giglio, D. Roy, L. Boschetti, I. Csiszar, D. Davies, S. Korontzi, W. Schroeder, K. O’Neal, J. Morisette, 2011. MODIS-Derived Global Fire Products. In: Ramachandran, B., Justice, C.O., Abrams, M.J., eds., Land Remote Sensing and Global Environmental Change. Remote Sensing and Digital Image Processing, Springer New York, 661-679.
Roy, D.P., P.E. Lewis, C.O. Justice, 2002. Burned area mapping using multi-temporal moderate spatial resolution data – a bi-directional reflectance model-based expectation approach. Remote Sensing of Environment, 83, 263-286.