Earthquake Early Warning Limitations

In a newly published study, U.S. Geological Survey scientists and their partners calculate possible alert times that earthquake early warning systems can provide people at different levels of ground motion from light to very strong shaking. 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. (Public domain.)