A semantic framework to characterise and monitor territories affected by environmental risks

When natural disasters occur, the primary concern of authorities responsible for the public safety is to organise and enforce the relief in an as quick as possible and effective way. Detailed information on what kind of hazard has occurred, and on how it is evolving or is expected to evolve, is crucial for the safety authority to prepare and enforce a rescue plan that puts in safety the lives of the citizens which are under the hazard's threat. On the other hand, such an information alone is useless if not correlated and contextualised on the territory where the hazard has occurred. In this paper we present the design of a semantic information model which integrates different information domains into a unified framework. In particular, three ontologies have been defined to represent respectively the information domain of the environmental risk, the domain of sensors (which are responsible for measuring the phenomena that may trigger hazards) and the geographic domain. The unified model, used along with a geographic map, can be used to characterise places (from a single building to an entire region) from the risk point of view. The resulting knowledge base can then be used to build monitoring services capable of identifying on the territory those sensing units whose sensed data are really useful for the set-up of a relief plan. A prototype of such a monitoring tool has been implemented. A use case example focusing on the wildfire hazard is discussed in the paper.