Tsunami risk perception in Central and Southern Italy, 2021

The tsunami risk perception survey is promoted by the Tsunami Alert Centre of the National Institute of Geophysics and Volcanology, operating within the Italian System for Tsunami Alert (SiAM) with the Civil Protection Department and ISPRA, and acting as Tsunami Service Provider in the NEAMTWS.

Conducting studies on tsunami risk perception is important in order to obtain data on population’s knowledge and awareness, and understanding people’s perception of tsunami risk. These data are going to be added to those from two previous surveys on tsunami risk perception being issued in 2018 and 2020, to integrate the available knowledge on these issues and will provide publics, experts and policy makers with relevant tools to implement risk mitigation policies. 

The third phase of the survey was completed in January 2021, administering a total of 4,207 questionnaires to the population living on the coastal areas of Sicily, Campania, Latium and Sardinia, in addition to the 1,635 interviewees considered in previous surveys.

The survey used a semi-structured questionnaire consisting of 27 items, with closed alternative questions, and four sets of Likert scale questions. The questionnaire was optimized for CATI administration, taking into account the need for conciseness and comprehensibility of the questions.

All the studied regions are located in the central Mediterranean basin (including central and southern Tyrrhenian Sea, Sardinian Sea, Sicily Channel), some of which are characterized by high tsunami hazard, and in some cases they have been affected by recorded tsunamis in a close or distant past. Some regions are located in areas where potential seismic tsunami sources are present, others surround waters where active volcanoes exist, both on islands (such as Stromboli, Vulcano) and below the sea (Marsili, Palinuro). 

In addition, the four studied regions have a high risk exposure due to the high density of population living on, or visiting the coastal areas for tourism. In the areas where the questionnaire was administered, five highly populated regional capitals are located, including Palermo, Messina, Naples, Rome and Cagliari, together with other important towns (such as Catania, Siracusa, Trapani, Salerno, Olbia etc.). Moreover, the coastal shores involved in the survey, live of a significant tourist affluence in the summer period (and not only), with many tourist facilities and large hotels located along the coasts.

The survey's main aim is to analyze the perception of tsunami risk by the coastal population and to correlate levels of tsunami risk perception with scientific data from probabilistic tsunami hazard assessment (PTHA) for the considered coastal area. We will present some preliminary results of this last survey, with a comparison with the previous analyses on other regions in southern Italy.