Android earthquake alert: Google admits algorithm-driven system limitations

Business Standard

28-07-2025

After two years, Google has reportedly admitted that its earthquake early warning system, dubbed Android Earthquake Alert System, failed to accurately alert people during Turkey's deadly quake of 2023. According to a BBC report, the US technology giant accepted that rather than sending its highest level alert to ten million people within 98 miles of the epicentre, it only sent such alerts to 469 users during the first 7.8 magnitude earthquake.
Getting this alert on time would have given people around 35 seconds of warning to take precautionary measures, added the report. Some might be wondering why Google failed to send such alerts to the victims timely manner, whereas some might be wondering how Google will even detect which people will be affected by the earthquake. Let's find the answers to these questions and more:
What is Google's Android Earthquake Alert System, and how does it work
Google's Android Earthquake Alert System is a mechanism that detects early signs of seismic activity or earthquakes. It relies on motion sensors built into Android smartphones to detect it. When a potential earthquake is identified, the system uses an internet connection to send alerts to nearby Android users who might be affected by strong ground shaking. Additionally, when people search for earthquake-related information on Google, the system provides real-time details about recent tremors in the area along with safety tips.
For the uninitiated, most Android phones come with accelerometers – sensors that detect movement and orientation. These can also act like small earthquake detectors. The sensor can pick up the earliest signs of ground shaking as it uses your phone's accelerometer to sense the initial tremors (P-waves) of an earthquake.
If several phones in the same area detect similar shaking at the same time, Google's servers analyse the data to estimate whether an earthquake is happening, where it started, and how strong it might be. Alerts are then sent to nearby phones using the internet. Since internet signals move faster than earthquake waves, people can often get a warning a few seconds before strong shaking begins.
Types of alert notifications and what they mean
Google's Earthquake Alert System issues two types of notifications when a quake of magnitude 4.5 or higher is detected: 'Be Aware' and 'Take Action' alerts.
The 'Be Aware' alert is intended for areas expected to feel mild tremors. It follows the phone's standard notification settings, including volume, and offers more information once tapped.
On the other hand, the 'Take Action' alert is triggered in regions at risk of moderate to severe shaking. This alert overrides the user's notification settings—it plays a loud alarm and wakes the screen to immediately draw attention.
Both alert types direct users to safety guidelines and show a map with the estimated epicentre and magnitude of the quake.
Where did it go wrong with the Turkey earthquake
According to the BBC, Google researchers have detailed in the Science journal what caused the system failures, pointing to flaws in the detection algorithms as the main issue. During the first earthquake, the system mistakenly estimated the magnitude to be between 4.5 and 4.9 on the moment magnitude scale (MMS), when the actual quake measured 7.8.
Later that same day, another powerful earthquake occurred, but the system again misjudged its severity. As a result, only 8,158 people received critical 'Take Action' alerts, while nearly four million received lower-level 'Be Aware' notifications. Following these events, Google updated the algorithm and ran a simulation of the initial quake. This revised system would have issued 10 million 'Take Action' alerts to people in immediate danger, and sent 67 million 'Be Aware' alerts to those farther from the epicentre.
BBC quoted Google researchers as saying: "Every earthquake early warning system grapples with the same challenge – tuning algorithms for large magnitude events.'
What leads to Google's earthquake detection system's unreliability
While Android phones help create a wide earthquake detection network, their sensors aren't as accurate as professional-grade seismometers. Data from smartphones can be affected by movement or noise, which makes it harder to correctly estimate the strength of an earthquake.
One of the main challenges is determining the quake's magnitude early enough to send timely alerts. But the first few seconds often don't provide enough data, forcing a tough choice between speed and accuracy. Getting it wrong either way, by underestimating or overestimating, can cause problems. For instance, the system failed to correctly assess the size of the 2023 Turkey earthquake, raising concerns about the reliability of early warnings.
Another limitation lies in the system's reach. It depends on having enough Android phones in an area with good internet access. Regions with fewer devices, like remote areas, rural zones, or oceans, might not be covered well, leaving detection gaps. Even when an earthquake is detected and measured accurately, the impact on the ground can differ from place to place. Factors such as soil type or building design can influence how strongly people feel the shaking. This means that even with precise alerts, some users might still receive misleading warnings or none at all.
Google itself has clarified that the system is supposed to be supplementary and is not a replacement for national systems.