The limits of earthquake early warning: Timeliness of ground motion estimates

Science Advances
By: , and 

Links

Abstract

The basic physics of earthquakes is such that strong ground motion cannot be expected from an earthquake unless the earthquake itself is very close or has grown to be very large. We use simple seismological relationships to calculate the minimum time that must elapse before such ground motion can be expected at a distance from the earthquake, assuming that the earthquake magnitude is not predictable. Earthquake early warning (EEW) systems are in operation or development for many regions around the world, with the goal of providing enough warning of incoming ground shaking to allow people and automated systems to take protective actions to mitigate losses. However, the question of how much warning time is physically possible for specified levels of ground motion has not been addressed. We consider a zero-latency EEW system to determine possible warning times a user could receive in an ideal case. In this case, the only limitation on warning time is the time required for the earthquake to evolve and the time for strong ground motion to arrive at a user’s location. We find that users who wish to be alerted at lower ground motion thresholds will receive more robust warnings with longer average warning times than users who receive warnings for higher ground motion thresholds. EEW systems have the greatest potential benefit for users willing to take action at relatively low ground motion thresholds, whereas users who set relatively high thresholds for taking action are less likely to receive timely and actionable information.

Study Area

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title The limits of earthquake early warning: Timeliness of ground motion estimates
Series title Science Advances
DOI 10.1126/sciadv.aaq0504
Volume 4
Issue 3
Year Published 2018
Language English
Publisher American Association for the Advancement of Science
Contributing office(s) Earthquake Science Center
Description eaaq0504; 10 p.
Country United States
State California
Other Geospatial Oakland