Advancing earthquake preparedness: a survey on public perception of Earthquake Early Warning Systems in Croatia

Abstract

Earthquakes are rare and unpredictable events that strike suddenly and without warning, precluding the issuance of alerts common to other natural or anthropogenic hazards.  Due to the widespread unpreparedness of the population, even moderate-intensity earthquakes may pose a significant threat to human health and safety. A crucial advancement in reducing such seismic risks, especially in densely populated areas, are Earthquake Early Warning Systems (EEWS), which operate by monitoring the ongoing seismic activity in real time. By detecting the initial, faster, yet less destructive primary (P) seismic waves, EEWS can provide a warning before the arrival of the slower, but more devastating secondary (S) waves, thereby enabling people to undertake at least basic personal and automated protective actions. 

While the effectiveness of the EEWS has been proven in various contexts worldwide, their implementation in Croatia faces unique challenges. The proximity of the seismogenic faults to the urban areas, exemplified by the 2020 Zagreb earthquake’s epicentre being just 7 km from the city centre, significantly reduces the warning times, thus undermining the utility of the EEWS.  Beside the geographical challenges, the implementation of EEW systems require also significant material investments and technical expertise, factors dependant on the society's ability and willingness to invest in the necessary infrastructure and to support the initiative.

In this contribution, a survey on public perception regarding EEWS was conducted through a 27-item questionnaire, distributed online (via Google forms) among various Croatian demographic sectors. Responses from 121 participants, a majority of whom (87%) have experienced significant seismic activity, were analysed. The survey reveals that, prior to the study, only about half of responders were aware of EEWS, with a mere 5% having utilized earthquake warning applications. Despite being informed about their reduced effectiveness in Croatia, most of the respondents still expect that early warnings, if available, would enhance their sense of safety. Furthermore, while the majority think they would react appropriately to early warnings, there is nevertheless a strong advocacy among the participants for public educational initiatives to improve earthquake preparedness and knowledge about personal protection measures. 

The overall survey results suggest a general-public support for investments aimed at mitigating seismic risks in Croatia. While seismographic conditions limit the utility of early warnings mostly to post-event information, the integration of such systems within broader crisis-management frameworks may aid in organizing post-earthquake emergency responses and reducing confusion and panic among the population.