Risk and ecoregion implications of wildfire statistics in Portugal

Coordinator: José Miguel Cardoso Pereira
UTAD/CITAB Coordinator: Mário Jorge Modesto Gonzalez Pereira

TWO-SENTENCE SUMMARY: This ‘advanced’ research project will examine Portugal wildfire statistics for the purpose of probabilistic risk assessment and ecological/climatologically basic research. The Portuguese Team will provide regional datasets from Portugal and knowledge of local climatology/ecology and the British Team will provide experience in using the statistics methods and techniques.

[Note: We have purposely kept this description ‘general’, aimed at the average intelligent layperson, and with fewer than ‘normal’ references.]
Wildfires worldwide are known to result in numerous fatalities and loss of infrastructure, with additional significant impacts on climate and ecosystems. Portugal, like many Mediterranean countries, has recently experienced some particularly severe wildfire seasons. For example, in 2003 Portugal had about 450 000 hectares burned and 20 confirmed deaths (DGF, 2003). Recently, a number of researchers (e.g., Schoennagel et al. 2004; Cleland et al. 2004) have emphasized the need for regional-level examinations of wildfire-regime dynamics and changes, and the factors driving them. With implications for hazard management, climate studies, and ecosystem research, there is, therefore, significant interest in appropriate analysis of historical wildfire databases, particularly when coupled with knowledge of the regional climatology and ecology.

We propose to do an extensive regional analysis of wildfires in Portugal, using techniques and methodologies for characterizing the statistics of wildfires (British Team), applied to wildfire data sets available in Portugal (Portuguese Team). Over the last ten years, both teams have published research to do with wildfires (see references for each team in “details of up to six recent relevant publications”), but the British Team will bring to this collaboration specific methodologies and ideas which they have used and published in a variety of locations, including high impact factor journals Science (Malamud et al. 1998) and Proceedings of the National Academy of Sciences USA (Malamud et al. 2005); this research has had a certain impact in wildfire community research and was the original source of the Portuguese Team contacting the British Team for a proposed collaboration.
In the British Team’s most recent research, which will be similar to what will be done in Portugal, Malamud et al. (2005) took a high-resolution database of 89 000 wildfires for the USA over three decades, and considered the occurrence of wildfires as a function of 18 ecoregions (land units classified by climate, vegetation, and topography), ignition source (anthropogenic vs. lightning), and decade. They found that in each of the ecoregions, the wildfires followed robust frequency-area power-law behaviour; in other words, that there were very few small wildfire burned areas, more medium areas, and a large number of very small wildfire areas. From these statistical analyses, with appropriate understanding of ‘errors’ involved in the analyses of the frequency-size statistics, the authors were able to (i) make conclusions about the relative scaling of wildfire-burned areas in different USA ecoregions, and the ecological/climatological drivers for systematic differences observed between ecoregions, (ii) calculate recurrence intervals for wildfires of a given burned area of larger for each ecoregion, allowing for the classification of wildfire regimes for probabilistic hazard estimation.
It is then proposed, in this collaboration, to take the British Team’s existing experience in these statistical methodologies and combine this with the Portuguese Team’s experience with the Portugal regional data along with their existing knowledge and previous research of Portuguese climatology/ecology. The Portuguese Team has an extensive wildfire database (obtained from the Portuguese Forest Service) which includes over 400 000 records with burnt area, date and location for wildfires in Continental Portugal (1980–2003).
We believe that the collaboration is a logical one, with a combining of expertise that each of the other team’s is lacking. As one final note, for the last couple of years the main applicants of both the Portugal and British Team have been in e-mail contact, and discussed the possibilities of joint research via e-mail, but without a ‘face-to-face’ meetings, these discussions have floundered a bit. We believe that the physical presence of the two teams together is what is needed to push towards a successful beginning and significant advanced towards completion of this research.

Project Details





Start date

May 2006


12 months

Total Financing

1.500,00 €

Responsible institution

Instituto Superior de Agronomia