The California Earthquake Warning app is now available on more devices

California’s free earthquake early warning app is now available for Mac computers and Chromebooks, a major expansion of access to the warning system that has been available on cell phones for years.

The MyShake app, developed by UC Berkeley, is one of the most popular ways to receive early earthquake warnings generated by the US Geological Survey’s ShakeAlert system, which provides alerts in California, Oregon and Washington. The app has been downloaded nearly 4 million times since its launch in late 2019.

MyShake was already available on iPhones, iPads and Android phones. UC Berkeley is also working to make MyShake available for the Windows operating system, said Richard Allen, director of the Berkeley Seismology Laboratory.

More than half a million people in California received early warnings through MyShake on Dec. 5 of a magnitude 7 earthquake that struck the Pacific Ocean 30 miles off the coast of Humboldt County and on Dec. 9 of a magnitude 5.7 earthquake centered about 50 miles southeast of Reno, which was widely felt throughout central California.

Some users received up to 15 seconds of warning before they felt like they were being shaken by the earthquake off Humboldt County, officials said. And some people were warned more than 10 seconds before the Nevada earthquake.

On August 6, more than 517,000 early warning messages were sent to MyShake users 5.2 magnitude quake That hit Kern County near the Grapevine section of Interstate 5. People across Southern California said they got a few seconds’ warning before they started shaking.

Earthquake early warning systems are based on the scientific principle that vibration waves traveling through rock travel more slowly than today’s telecommunications systems – similar to how you might see lightning seconds before you hear thunder.

For example, it would take more than a minute for a magnitude 7.8 earthquake originating in the Salton Sea along the San Andreas Fault to be felt 150 miles away in Los Angeles.

The further you are from the epicenter, the more likely you are to receive more warnings. However, if you are very close to the epicenter, the warning may not arrive until you have already started shaking.

The USGS ShakeAlert system relies on a variety of seismic sensors in the ground to instantly detect shaking. This information is then sent to computers to determine whether and where to send an alert.

Officials are advising people to drop, hide and hold on if they hear an impending tremor warning.

Gov. Gavin Newsom welcomed the expansion of the MyShake app, delivered in partnership with the California Governor’s Office of Emergency Services, to more devices.

“I encourage Californians to download the MyShake app on their phones, laptops or tablets to receive these important alerts and to ensure emergency notifications are enabled on mobile devices,” Newsom said in a statement.

The MyShake app is set to trigger alerts when a quake is estimated to be magnitude 4.5 or greater and the intensity of the shaking at the phone’s location is expected to be at least magnitude 4.5 “weak” – defined as level 3 on the modified Mercalli intensity scale. This intensity of shaking is defined as an intensity that is noticeable to people indoors, especially on the upper floors of a building, and can cause cars to rock slightly. Some people indoors may compare the feeling to the vibrations of a passing truck.

Apple says there’s a setting you can change on your iPhone to improve the speed, accuracy, and reliability of emergency alerts. To do this, you can enable “local awareness” by going to “Settings” and then “Notifications.” Scroll down to “Government Alerts,” then tap “Emergency Alerts” and navigate to the option.

On its website, MyShake suggests opening the app every month or so to keep it “up to date and ready to receive notifications.” Leaving the app unused for a long period of time may cause the app to go into deep sleep.”

An easy way to do this, MyShake suggests, is to click on the app when it notifies you – without urgent, alarming warning tones – of a major earthquake somewhere in the world, which typically occurs every two weeks. “By tapping this notification and opening the MyShake app, you can keep the app up to date and not rely on your own reminders.”

MyShake is now also available in six languages: English, Spanish, Tagalog, Korean, Vietnamese and Chinese – the latter in Mandarin and traditional characters. MyShake uses the first language supported in your device’s language and region settings. However, on an iPhone, you can change the language by going to Settings, then Apps, and selecting MyShake before choosing a preferred language.

People who don’t have a computer or smartphone can still receive earthquake warnings on their cell phones – but only for those where a stronger or stronger shaking is predicted in their location. These alerts are sent via the Wireless Emergency Alerts system, similar to Amber Alerts.