Feasibility and Interest in Earthquake Early Warning Systems for Areas of Moderate Seismicity: Case Study for the Pyrenees

Abstract

International audienceSeismic risk in areas of moderate seismicity (AMS) is a reality and destructive earthquakes may occur there. This is why stakeholders and risk managers in these areas show an increasing interest in Earthquake Early Warning Systems (EEWS) and are wondering about the possibility of equipping their territories with such systems. This question of feasibility has to be broached globally: distinguishing technical feasibility from notions of opportunity and utility, an, thus, it has to involve both scientific experts and stakeholders. Moreover, it is necessary to consider each situation specifically without any preconceptions, specifically concerning potential uses that can be made of early warnings, in particular, it is clear that when applied to AMS, the EEWS principles translate into shorter lead times than the ones expected for more seismic areas and would, consequently, require considering new ways of using early warnings. Through the experience conducted for the Pyrenees (France–Spain border) as part of the SISPyr project, this study aims at identifying responses to the potential value of EEWS as real-time seismic risk mitigation tools for AMS as well as to offer a methodological framework to guide stakeholders in their assessment of opportunities to set up EEWS

Accuracy and Uncertainty Analysis of Selected Methodological Approaches to Earthquake Early Warning in Europe

“…From an engineering perspective for example, these uncertainties play a central role in the real-time probabilistic seismic hazard analysis framework that can be used to determine whether issuing an EEW alarm would reduce the losses associated with an incoming event (Iervolino, 2011). Our work therefore represents a significant advancement over many previous studies of context-specific EEW accuracy (e.g., Hsu et al, 2018;Xu et al, 2017;Kodera et al, 2016;Böse et al, 2012;Colombelli et al, 2012;Hsu et al, 2016;Böse et al, 2012;Colombelli et al, 2015;Hoshiba and Aoki, 2015;Böse et al, 2014;Doi, 2011;Hartog et al, 2016;Mittal et al, 2019;Chen et al, 2019;Chung et al, 2020;Minson et al, 2020;Zollo et al, 2009;Cochran et al, 2018;Festa et al, 2018;Auclair et al, 2015) -including those that examine Virtual Seismologist (Behr et al, 2016) and PRESTo -which focus exclusively on the performance of point-estimate predictions (i.e., that only consider mean or modal values of the estimates rather than their probability distributions) from EEW algorithms. Some work has examined uncertainty propagation for EEW (i.e., the effect of uncertain source-parameter estimates on the final ground-shaking predictions), but this has so far been limited to the context of hypothetical algorithms (Meier, 2017), simplistic simulated events (Iervolino et al, 2009), or empirical error models of parameter estimates (Brown et al, 2011).…”

Facilities management and earthquake risk reduction: The TURNkey project

“…Like with OEF, the effectiveness of EEW depends on the accuracy and timeliness of EEW alerts as well as their ability to deliver actionable information that can lead to protective actions taken by message receivers [12]. The primary aim of EEW is to reduce damage, costs and casualties through personal action (e.g., drop, cover, hold-on) or system action (e.g., automated control) [13,14,15]. Whilst the primary use of EEW amongst members of the general public is to support their safety, use amongst business and critical infrastructure end-user groups is more varied, with organisations integrating the alerts into their disaster management and business continuity planning (e.g., autonomous control, workplace safety alerts, early triggering of response plans etc.)…”

Earthquake early warning in countries where damaging earthquakes only occur every 50 to 150 years – The societal perspective

“…Nakayachi et al [13] and Sutton et al [52] also stressed the latter research gap when they state the need to better explore what information elements are most important when the alert time is short, and how should the information best be presented. Further, Auclair et al [16] highlight a research gap with regards to the exploration of public attitudes towards and expectations of EEW systems in countries with moderate seismic hazard levels; only professional stakeholders have been involved in such countries so far. For our Swiss case study, we thus focused on the following two research questions:…”

“…Despite being less frequent, strong or catastrophic events still have to be expected in countries with moderate earthquake hazard. Therefore, it is important to assess the potential of EEW systems also in these countries [16], to assess their potential from a societal perspective, and compare it with that of other countries.…”