Earthquake Alerts: Early and Often? Or Possibly Late?
Detailed Description
The choice when issuing earthquake warnings is to: 1) issue alerts for weak shaking and potentially provide long warning times, but risk sending alerts for the many events that do not go on to produce damaging ground shaking, or 2) issue alerts only when ground shaking is expected to be damaging, with the tradeoff that the alert will be sent much later, reducing the amount of time available to take action.
Sources/Usage
Public Domain.