Great expectations for earthquake early warnings on the United States West Coast

Incorporating Intensity Distance Attenuation Into PLUM Ground‐Motion‐Based Earthquake Early Warning in the United States: The APPLES Configuration

“…For EEW alerts to the public, Precautionary alerts to locations of likely-felt shaking may be more tolerated compared to Precautionary alerts to locations of likely-notfelt shaking, as alert recipients that feel shaking will know right away that an earthquake has occurred and that alerts may have been needed elsewhere (Allen et al, 2018;McBride et al, 2020). Additionally, some members of the U.S. public have expressed interest in receiving EEW alerts at felt shaking levels (Bostrom et al, 2022). For our analysis, we consider the transition between likely-felt and likely-not-felt shaking to happen at MMI 3.0, using the MMI definitions described in Dewey et al (1995).…”

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

“…In this section, we highlight the relevant societal aspects related to EEW systems, namely the history of public alerts, the dissemination channels, the thought process about setting meaningful thresholds, the importance of actionable message content, the technical limitations and preferences with respect to warning times, people's reactions when receiving warnings, and the need of postalert messages. Overall, public perception of the usefulness of EEW alerts is known to be high in the US [18], Mexico [19], Japan [13], Peru [20], and New Zealand [14].…”

“…However, another study showed that people in Japan reported that they took physical protective actions in a nursery, kindergarten, school, at home, and at work [51]. People tend to respond more actively especially when an earthquake generates strong shaking or when their fear level is high [18]. In addition to mentally preparing themselves for the shaking or taking protective actions, many people also tend to look for further information to verify the warning [13,52], warn their relatives [20,26], or interact to build a joint understanding of what will (is) happen(ing) [13,46].…”

“…Most users in the US perceive EEW alerts as useful and tolerate false alerts as they offer practical training opportunities [2]; however, post-alert update messages with context and explanations are expected [18]. In Japan, users also expressed a positive attitude towards false alerts after the Tohoku earthquake, arguing that they represented an opportunity to practice protective actions [55].…”

Earthquake Early Warning in Countries Where Damaging Earthquakes Only Occur Every 50 to 150 Years – the Societal Perspective

“…Most users in the US perceive EEW alerts as useful and tolerate false alerts as they offer practical training opportunities [2]; however, post-alert update messages with context and explanations are expected [18]. In Japan, users also expressed a positive attitude towards false alerts after the Tohoku earthquake, arguing that they represented an opportunity to practice protective actions [55].…”