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 have 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."
When will the Bay Area get a similar app?
UC Berkeley Seismological Laboratory Director Richard Allen said the sensors for the early warning system for Northern California are being installed.
But no one has invested in building one for the Bay Area.
"Hopefully, we will have it very soon," said Allen. "But there are also all of these other mechanisms that are currently underway to deliver ShakeAlert to users across the Bay Area."
BART and PG&E are part of a pilot program so they can shut down their equipment seconds before a quake. Allen said he hopes the app in Los Angeles will encourage other cities to develop their own delivery systems to the public.
This story includes reporting from KQED's Monica Samayoa.