The Android Earthquake Alerts System turns phones running the mobile operating system into mini seismometers. Following last night’s earthquake in Los Angeles, Google shared an interesting visualization of what Android phones detected.
Android engineering VP Dave Burke tweeted a video showing Los Angeles and the surrounding area moments after the earthquake. P-waves (shown as yellow dots) appear first and are followed by red ones for the S-wave. The concentric circles are the “expected locations of the P and S waves.” As the latter one passes, you see the yellow markers turn red.
As we noted in our explanation last month:
The accelerometer on smartphones today are capable of detecting that initial wave. When that occurs, your phone will send a general location to Google’s earthquake detection server. This city-level data does not include precise zip codes or street addresses.
That data is then compiled in real-time. Google is not yet using this system to send alerts. Rather, Google surfaces a card in Search for users looking up “earthquake or other related queries. It asks if you felt shaking to “share a fast, accurate view of the impacted area.”
Over the coming year, Google will actually send notifications and is targeting this system for areas that do not have a ground system of seismometers already in place.
Meanwhile, in addition to this phone-based network, Google in August integrated the early warning ShakeAlert system from California and the United States Geological Survey. It successfully fired last night and started with an “Earthquake nearby” notification that tells you to “expect shaking” and how far away the tremor was, as well as the estimated magnitude. Tapping opens a card-based feed of useful information like safety tips and a map with your location from the epicenter.
Author: Abner Li
Source: 9TO5Google
