Assessment and management of cascading effects triggering forest fires

Abstract

A crisis situation may be due to the occurrence of a single hazard event with large impacts or due to several hazard events occurring simultaneously. Hazard events occurring at the same time may have independent causes or may result from a sequence of triggering effects. The outcome of a situation for which an adverse event triggers one or more sequential events is generally called “cascading effects”. The perception and understanding of the potential occurrence of cascading effects is of great relevance for planning and response activities since an unexpected scenario in an emergency may worsen the situation endangering people, goods, and may nullify a strategy that was developed accounting for a scenario in which the triggering event was considered as a single occurrence. This paper presents an analysis of possible scenarios of cascading effects triggered by an earthquake. A detailed quantitative example in which an earthquake causing an electric cable failure that potentially ignites a fire is presented. In particular, a methodology to assess the occurrence probability of the event chain earthquakecable failurefire ignition is presented. The final results are presented as conditional probability maps representing each transition, namely: earthquakecable failure, cable failurefire ignition, and the assessment of the full path earthquakecable failurefire ignition. This study is a part of a pilot application built to test the integrated crisis management system which is being developed in the FP7 European Integrated Project – CRISMA (“Modelling crisis management for improved action and preparedness”).