Speaker/Affiliation: Jeffrey J McGuire, USGS
Title: The ShakeAlert Earthquake Early Warning System: Current Status and Future Possibilities
When: Friday, February 6 12:00pm PST
Location: EMS B214
Abstract: The primary goal of the ShakeAlert Earthquake Early Warning System is to provide useable warning times before potentially damaging shaking. Version 3 of the underlying algorithm base, live since March 2024, includes numerous improvements aimed at ensuring success in large earthquakes including: multiple ways to initiate events, independent data streams for seismic and geodetic data, and multiple algorithms that characterize large ruptures. It prioritizes speed over ground-motion prediction accuracy to some extent within 100 km of the epicenter. I will give an overview of expected performance from offline testing and recent large earthquakes. I’ll also discuss some recent additions to the group of automated actions implemented by our partners that deliver alerts including the L.A. Unified School District.
ShakeAlert has clear remaining challenges and several promising areas for system refinement. USGS allows our partner organizations a range of choices in how they alert their users which requires the system produce accurate estimates across a range of magnitude and ground motion levels. Clarifying what types of alerts to avoid versus where over-alerting is acceptable, particularly for large public delivery mechanisms, is a key current issue. ShakeAlert is funding a variety of research projects focused on understanding the negative outcomes of alerting to improve our strategies and potentially add more tailored products. On the algorithm side, ShakeAlert has a well-documented weakness for earthquakes that initiate outside the sensor networks, particularly offshore in subduction zones. Several algorithm approaches and new data types such as coastal arrays and fiber optic sensing are being tested to improve our alerts in these cases.
