When a rare 5.9 earthquake struck Virginia a few years ago, some people in New York City heard about it on Twitter seconds before the actual rumbling reached them.
Now a group of researchers has proposed a better way to use smartphones to provide earthquake warnings, giving affected locations a crucial few seconds to get to positions of safety.
In the journal Science Advances, researchers from the U.S. Geological Survey, Caltech, the University of Houston, and others, describe a crowdsourced GPS-based earthquake warning system that would send out a message when it detects the initial rumbling. By tapping many phones in the same area, the system could detect when GPS readings all jump at the same time and figure out there’s an earthquake happening.
The study involved a simulation of a magnitude 7.0 earthquake on California’s Hayward fault and a test using real data from the major 9.0 earthquake and tsunami in Japan in 2011. In both cases, Google’s Nexus 5 smartphone could detect small geological shifts of about one centimeter. In Japan, it would have sent warning before waves of the earthquake hit Tokyo.
According to LiveScience, the researchers are now working to do a field test using 250 smartphones in Chile. The problem is that they have to hack the smartphones to do it, because manufacturers don’t make the raw GPS data available that would be needed.
Today, early earthquake warning systems exist in Japan and Mexico that use seismometers and other scientific equipment. While they are more accurate than smartphones would be, they are also more expensive and difficult to implement. This study shows that for medium or strong earthquakes, crowdsourced smartphone systems could provide much cheaper, “good enough” data to give a few crucial seconds.
Even California could use something like that today. It is still hunting for funding from Congress to fully build its warning network.