Friday, an earthquake reaching a magnitude of 6.4 occurred just north of Ridgecrest, California, and residents across Los Angeles County felt it. However, the city’s earthquake notification system, ShakeAlertLA, didn’t give people in the area any warning before the event.
Though the impact across Los Angeles was relatively minor, after feeling tremors many residents feared stronger waves would follow. Many people also wondered why the earthquake warning system, which the city endorsed in 2018, now left them in the dark.
The app has only been available as of the end of last year. Therefore, this earthquake prompted the system’s first live test.
While many people are understandably confused and concerned by the lack of expected notifications, nothing went wrong.
How ShakeAlert Earthquake Detection Works
ShakeAlert detects the presence of incoming tremors by measuring the primary waves of an earthquake. While relatively harmless, these primary waves move faster than an earthquake’s secondary waves, which cause the shaking that people feel above ground.
Utilizing monitoring stations across the West Coast, ShakeAlert reads the strength of these waves and sends out alerts if warranted. As of now, regions throughout California, Oregon, and Washington use the system, which primarily supports emergency services. As such, general consumers can’t yet access this kind of technology. However, hospitals, transportation systems, and similar organizations depend on it.
While people can anticipate dangerous tremors, the system only detects them a short time before the impact of the secondary wave.
Obviously, even a moment’s preparation has lifesaving potential when it comes to large-scale earthquakes. Even during smaller ones, the peace of mind gained from knowing what to expect is incredibly valuable in its own right.
Why Nobody Received an Earthquake Alert
According to ShakeAlert’s designers, the system did detect the recent earthquake’s presence and operated normally by choosing not to send out notifications.
Ultimately, under the app’s reporting parameters, this 6.4 earthquake was not powerful enough to warrant a message. Whether or not users expected the outcome of these defined limitations, technically, ShakeAlert operated as it should have.
Following the earthquake, ShakeAlert explained the system features a higher magnitude requirement to avoid creating an oversaturation of notifications. People already ignore lots of notifications across their devices. So, developers felt too many alerts for minor earthquakes would discourage user attention. To maintain general faith in ShakeAlert’s system and prevent people from ignoring warnings, designers set high-magnitude reporting standards.
Regardless, due to feedback received following Friday’s earthquake, ShakeAlert’s head of communication expressed that they will be making adjustments to the app immediately.