Google is in the process of creating a global earthquake warning system powered by Android phones and the first part of this system was launched yesterday.
If you choose this system, accelerometer (sensors that measure the direction and force of movement) that is used in many smart devices and that is present in Android devices it will become a data point for an algorithm designed to detect earthquakes. Ultimately this system will send alerts automatically to people who may be affected.
The first step what is Google giving to be able to achieve this is that is partnering with the United States Geological Survey and the California Office of Emergency Services to send agency earthquake alerts to Android users in that state.
These alerts are generated by the existing ShakeAlert system, which uses data generated by traditional seismometers.
In the second and third stage Google's plan all Android phones will be included.
In the second step, it is where Google will show localized results in earthquake searches based on the data it detects from Android phones. The idea is that when you feel an earthquake, you go to Google to see if it is what you felt or not.
Finally, once you gain more confidence in the accuracy of the system, Google will begin to actively send earthquake alerts to people living in areas where there is no seismometer-based alert system.
With this, an Android phone can become a "mini seismometer" because it is equipped with an accelerometer. The Android system uses the data from this sensor to see if the phone is shaking. It only activates when an Android phone is charging and not in use, to conserve battery life.
“We have found that Android phones are sensitive enough to detect seismic waves. When a seismic wave passes, they are able to detect it and normally see the two main types of waves, the P wave and the S wave. All phones can detect that something is happening like an earthquake, but then you need a lot of phones to make sure. about what
The P wave (primary wave) is the first and fastest wave emitted from the epicenter of an earthquake. The S wave (secondary wave) is slower, but can be much larger. Google's system is capable of detecting both. “A lot of times people won't even feel the P wave because it's smaller, while the S wave tends to do a lot more damage. The P wave can be something that tells you to prepare for the S wave. "
This data is processed in the classic Google way: using algorithms on the aggregated data from thousands of phones to determine if an earthquake is occurring.
Where traditional seismometers are expensive and accurate, Android phones are cheap and plentiful. Google can use filters and other algorithms to convert these numbers on earthquake data accurate enough to send alerts.
Google says its system can locate the epicenter and determine the strength of an earthquake.
Despite this, the fundamental physics of these waves means that there are limits to what is possible, he explains:
“The most important thing is that the phones closest to the earthquake can help people. remote users to know its existence. One of the limitations of the system is that we cannot notify all users before an earthquake hits them. Users closest to the epicenter of the earthquake are unlikely to have a warning in time, as we do not predict earthquakes in advance. "
This speed also means that Google's Android-based warning system will not have a person in the middle, as these warnings will range from "a few seconds" near the epicenter to 30 to 45 seconds outside.
“We have a lot of seismologists on the team who are literally on board with us. Among them is Richard Allen, who has devoted most of his career to earthquake early warning systems and was instrumental in the design of the ShakeAlert system, and who also built an earthquake detection system. land on the phone in the past "
Source: https://www.reuters.com