A multivariate approach to assess the structural determinants of large wildfires: evidence from a Mediterranean country

Abstract

This paper analyses the factors behind wildfire propagation in a Mediterranean European country, Portugal, using a set of variables related to vegetation and climatic, topography and human aspects. Spatial cluster analysis was used to find homogeneous regions, and two-part regression models were used to model the contribution of the different elements driving extensive fire propagation. Our findings confirm the presence of spatial variability in the contribution exerted by most structural factors driving large wildfire spread. Additionally, the results of this study show that vegetation types, in particular the presence of shrubs, and a lack of human activities, such as agriculture, represent the main factors facilitating fire spread in this region, corroborating information from previous work. This research provides relevant input for implementation in different fields, from large fire awareness and prevention to the development of wildfire policies, as well as addressing methodological concerns in fire danger and fire risk analyses.