LA Now Has An Earthquake Alert App To Warn Us Before The Big One Hits

A bridge in Oaxaca, Mexico after a magnitude 8.1 earthquake. A quake of similar strength could hit California any time. (Rebecca Blackwell/AP)

Mayor Eric Garcetti officially unveiled an app Thursday morning that lets users know when a major earthquake is about to shake Los Angeles County.

The app, called ShakeAlertLA, sends notifications to let users know if a quake of 5.0 magnitude or greater has started, buying anywhere from a few seconds to tens of seconds before heavy shaking starts. That difference, says Caltech seismologist Tom Heaton, can "really affect how you react...before and during an earthquake."

Officials point out that the app does not predict earthquakes before they happen, but detects them early. According to a website associated with the app, the technology works by detecting P-wave energy — the first energy to emanate from an earthquake — allowing the app to detect where the earthquake is coming from, and how strong it will be. An alert is then issued to people who've downloaded ShakeAlertLA.

KPCC/LAist's head of podcasting, Arwen Champion-Nicks, has been spearheading a new podcast called "The Big One: Your Survival Guide," which details everything listeners need to know to get through a major earthquake in Southern California. She said the warning app could save lives.

"A few seconds of warning can make a huge difference," Champion-Nicks said. "It can be the difference between getting out of an elevator because the doors pop open, and being stuck in an elevator for 19 days. It can be the difference between having enough warning to get under your desk so nothing hits you in the head, and getting hit in the head so hard you don't remember that you have a desk."

The app was built by the city of Los Angeles in partnership with AT&T and using the ShakeAlert system developed by the U.S. Geological Survey. It's been well received so far, though some criticism has been levied over the fact that users are required to turn on their location to "Always On" in order to receive that potentially life-saving alert.

Still, it's probably worth considering, since "the science gives us every reason to believe that a big one is more likely than a 90210 reunion," Champion-Nicks said.

The app became available for download on Wednesday, for both iPhone and Android.

Want to know how to prepare for an earthquake? Have question about how to survive the Big One? Ask us below:


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