Perceived uses and responses to Earthquake Early Warning in Aotearoa New Zealand

Abstract:

Earthquake Early Warning (EEW) provides advanced notification of expected strong shaking from an earthquake. Upon receipt of such notification, pre-emptive actions can be taken to reduce damage to infrastructure, and prevent injuries and fatalities. Currently Aotearoa New Zealand does not have a national EEW system, so before investing in such technology, we undertook research to understand whether EEW would be useful and applicable in the New Zealand context. Our research consisted of (1) focus groups and interviews with relevant sectors (including utilities, infrastructure, emergency management, health and education), and (2) a survey of the New Zealand public (N=3084).

We found strong support for EEW for the purposes of undertaking protective actions for life safety; psychologically preparing for incoming shaking; activating emergency plans and undertaking situational assessments; and for taking actions that reduce damage to infrastructure. Sectoral participants stressed the need for EEW integration in terms of the development of system technology, notifications, and integration with other risk reduction measures (e.g. earthquake engineering, preparedness, mitigation). Public survey respondents expressed a desire for being warned at a threshold of NZ MMI 5-6 via mobile phone (supported by other channels). However, sectoral participants also suggested that a two-tiered threshold system might be desirable, similar to countries like Japan, where specific organisations receive notifications at lower thresholds than the public.

Respondents also wanted to receive messages that alerted them about additional hazards that may occur such as tsunami, other attributes of the earthquake such as its magnitude or location, and what actions to take. People indicated they were more likely to undertake quicker and easier actions for shorter timeframes of less than 10 seconds (e.g., stop, mentally prepare, take protective action such as drop, cover hold [on]), and more likely to move to a nearby safe area, help others, look for more information, or take additional safety actions as timeframes increased. The social science information we collected from these studies will guide future developments for EEWs in Aotearoa New Zealand.