Reassessing the Italian seismic hazard using soil classification

Almost two decades have passed since the publication of Italy’s official model of seismic risk (MPS04) by the National Institute of Geophysics and Volcanology (INGV). The model has undergone a thorough revision in the most recent years, leading to the new MPS19 model, still unavailable because the final evaluation steps required for its release are still in progress. The present paper aims to contribute to the awareness that physical risk measurements evolve over time with the accumulation of scientific progress, the processes’ evolution and new data availability. With this purpose, the probabilistic hazard derived from the baseline view of seismic risk provided by the MPS04 model is compared with that obtained under an alternative approach recently proposed in the geo-physical literature to take into account the soil characteristics. The relevant differences of the two models are analysed and the new hazard probabilities, useful for insurance purposes, are calculated. The differences with the baseline results are highly significant and a riskier picture for the Italian seismic hazard emerges.