CISN ShakeAlert: Development of a Prototype User Display for Providing Earthquake Alerts to End Users

Providing earthquake alerts (EA) requires fast and robust estimates of earthquake source and predictions of ground motion parameters shortly after the initiation of an earthquake. Over the past four years the California Integrated Seismic Network (CISN) has tested the real-time performance of three algorithms for providing EA in California. In the next two years we will migrate to an end-to-end prototype processing thread, called CISN ShakeAlert, which will provide a continuum of earthquake alert information. We have developed a User Display based on a Java applet to provide this information to a small group of collaborating test users. In turn, these test users will assist in developing procedures and formats that could be used to improve delivery of information via the ShakeAlert. The first version of the display runs on a user computer, and shows the user location, estimated location of the earthquake, location of the P- and S-wave fronts, estimated magnitude, as well as the predicted level of intensity of shaking at the user site and time until this shaking is expected to arrive. In future versions, we plan to assign uncertainty estimates to all predicted parameters.