Alaska may soon gain critical seconds, or even minutes, of advance warning before major earthquakes strike, thanks to a new study modeling the effectiveness of early warning systems across the state.
A new report finds that in many earthquake scenarios across Alaska, an early warning system could offer at least 10 seconds of advance notice before intense shaking begins.
Researchers Alexander Fozkos and Michael West from the University of Alaska Fairbanks say that increasing the number of seismic monitoring stations and improving their distribution could boost that lead time by an additional 5 to 15 seconds. Alaska is one of the world’s most seismically active regions, experiencing tens of thousands of earthquakes each year, including some of the most powerful on record.
Laying Groundwork for ShakeAlert Expansion
Published in the Bulletin of the Seismological Society of America, the study could help pave the way for expanding the ShakeAlert early warning system beyond California, Oregon, and Washington to include Alaska.
“There were a lot of studies before EEW was widely available on the West Coast, where people were looking at different scenarios,” said Fozkos. “So we wanted a similar kind of science up here with numbers that are Alaska specific.”
Timing Scenarios From Massive Quakes
For large earthquakes along major fault lines in coastal southcentral and southeast Alaska, the models predict warning times between 10 and 120 seconds for magnitude 8.3 scenarios.
Inland crustal faults in interior and southcentral Alaska showed warning times ranging from 0 to 44 seconds for magnitude 7.3 earthquakes.
For magnitude 7.8 quakes originating along the dipping edge of the subducting tectonic slab beneath Alaska, estimated alerts ranged from 0 to 73 seconds.
Surprising Results for Shallow Crustal Events
“I was expecting decent warning times along the coast and for most of the subduction zone events,” said Fozkos, because there is dense seismic station coverage in these areas. “I was not expecting decent warning times for the shallow crustal events, so that was the biggest surprise to me.”
The scenarios used in the study vary in earthquake magnitude, depth, location and fault style — all of which impacted warning times. The researchers’ models estimated how many seconds after an earthquake’s origin the quake could be detected, how many seconds after origin time an alert could be available, and minimum and maximum warning times at a location.
Warning times were defined as the time difference between the time of the alert and the time that peak ground motion from an earthquake arrived at a location. This definition differs from a more common definition used in EEW systems, which ties warning time to the arrival of the initial S-wave or shear wave of an earthquake.
The researchers wanted to use peak ground motion instead, to create a warning time measurement that might be more relevant to people as they respond to an earthquake. The initial S-wave may not always cause significant ground motion, and strong shaking can arrive tens of seconds after the initial S-wave in large earthquakes, they explain.
Challenges in Reaching the Public in Time
The study doesn’t analyze “the time it takes to disseminate the alert—the time it actually takes to send the alert from a radio tower or from a satellite to somebody’s phone and then for them to take out their phone and react to it,” Fozkos noted.
The potential lag time in transmitting data and sharing an alert with the public “could be a big challenge for Alaska, but I don’t think it’s going to be insurmountable,” he added.
Overcoming Harsh Conditions and Remote Locations
The harsh Alaskan winters and wilderness locations of some seismic stations could also be challenging for an early warning system, if stations go down and can’t be repaired quickly. “I think there is definitely a need for adding stations to cover redundancy for remote stations,” Fozkos said.
Ocean-bottom seismometers (OBS) and more earthquake detection via distributed acoustic sensing or DAS would also be welcome additions to a warning system, he added. “Coupled with the fact that some of our biggest earthquakes are going to be offshore, tsunamigenic threats, I think OBS and DAS are probably big targets for the future.”
Reference: “Earthquake Early Warning Scenarios for Alaska” by Alexander M. Fozkos and Michael E. West, 5 August 2025, Bulletin of the Seismological Society of America.
DOI: 10.1785/0120250051
Never miss a breakthrough: Join the SciTechDaily newsletter.
Follow us on Google and Google News.