Social and sector-based benefits of an earthquake early warning system (EEWS) for New Zealand

Abstract

Earthquake Early Warning (EEW) can be used to detect earthquakes and provide advanced warning of strong shaking, allowing pre-emptive actions that benefit life safety or infrastructure. We undertook focus group discussions and interviews with representatives from a range of sectors in New Zealand to scope whether they thought earthquake early warning (EEW) might be of use. We found that participants supported the idea of EEW in general but noted the challenges of applying it within their sectors. Primary benefits were perceived to be (1) life safety and/or health & safety; (2) psychological preparedness; (3) activation of emergency plans and situational assessment; and (4) organisational and site-specific actions to reduce damage impacts and aid response and recovery. Participants were more enamoured with automated or procedural actions that caused minimal description disruption for both their sector and the public, and were easy to turn on and off again. Given participants’ lack of experience with EEW some struggled to think of exact applications within their sector and it was noted that more detailed thinking needed to be done to work out exactly what actions might be beneficial. Participants were supportive of a nationally integrated EEW system, including a network of sensors, notification and messaging, earthquake mitigation and preparedness, and interaction across perils (e.g. tsunami). There was support for having a two-tiered threshold system for sending nationwide warnings similar to Japan, with specific sectors alerted at lower thresholds (e.g. MM4-6) and the public alerted at a higher threshold (e.g. MM6-7). In terms of warning notification channels, most participants suggested Emergency Mobile Alert cell broadcast as the key channel for notification, but also felt warnings needed to be propagated across a variety of other channels to ensure reach (TV, radio, mobile texts, computer notifications, control room/network centre notifications, public announcements, social media, staff supervisors). Participants generally agreed any messages should be simple, clear, easily digested, universally understood and directive, so as to promote appropriate action.