How can Haitians afford smartphones?

Smartphones can give early warning of earthquakes

American earthquake researchers have taken advantage of the fact that the GPS receivers in smartphones can sense shifts in the subsurface. You have developed an app with which an approaching earthquake can be detected at an early stage.

Children playing in Haiti's capital, Port-au-Prince, which was badly damaged by the earthquake: US researchers want to use the GPS sensors of smartphones to predict earthquakes earlier and warn the population.

Photo: UN Photo / Marco Dormino

Smartphones and other electronic devices with GPS receivers could help predict approaching earthquakes and issue appropriate warnings. This is particularly interesting for poorer and less developed countries and areas that cannot afford costly earthquake early warning systems. The only requirement for the reliability of the "ShakeAlert" is that the cell phone measurements come together in a swarm.

The smartphones work in a swarm

While some earthquake-prone countries such as Japan or the west coast of the USA have installed extremely complex early warning systems, many poorer countries often lack the financial means to do so. There could be an alternative for them in the future. The United States Geological Survey (USGS), which researches natural disasters, among other things, has worked with a number of American scientific institutes to develop an early-warning system for earthquakes in which smartphones play a central role.

If smartphones could already capture the first waves of an earthquake, it would be possible to warn people about the main waves.

Source: USGS

The idea behind this is that a network of smartphones in an area can provide enough data about the strength and spread of an approaching earthquake. The GPS receivers are able to recognize the movements of the earth moving underground from a certain strength.

The study comes to the conclusion that almost 5000 voluntary participants in this early warning system within a city are sufficient to detect an earthquake at least so early that there is enough time to get to safety.

The system measures the first waves of an earthquake

In fact, the new ShakeAlert cannot replace the sophisticated scientific early warning systems for earthquakes, but the trick to the functionality of the system lies in the swarm intelligence. "The fleet of cell phones works like a network of sensors," says Bob Iannucci, one of the participating scientists at Carnegie Mellon University. “When combined, many imprecise instruments can produce a more precise measurement. The application of the ShakeAlert has great potential, especially in areas where there is no network of scientific instruments. "

Earthquake in 1989 in the Loma Prieta district of San Francisco: US researchers not only want to use an app to detect earthquakes earlier, but also to warn the population more quickly.

Source: U.S. Geological Survey

The authors of the study tested their early warning system with data from the earthquake in Tohoku-oki, Japan with magnitude 9 and with simulated data for an earthquake with magnitude 7. The system measures what are known as primary waves. These waves are compression waves that are the first to propagate in an earthquake. The particles in the ground are pushed or pulled and move in the direction of propagation of the wave.

The early warning system via smartphone only starts from earthquake strength 7

The authors of the study say that strength 7 is roughly the limit at which the GPS receivers can register earth movements. It is true that even earthquakes with less strength can potentially cause great damage, and the new early warning system would, in the best case, give a warning time of a few minutes. "But even a warning of a few seconds can help," says the USGS. For example, to go to a protective corner, switch off the stove, open elevator doors or interrupt difficult operations. Because the speed of the electronic warning system is faster than the earthquake, areas outside the epicenter can also be warned.

The ShakeAlert earthquake early warning system is now to be tested on the Chilean coast.

Source: USGS

If a warning arrives on the smartphone, a map would show where the epicenter is, how strong the earthquake is and how many seconds it will take for the quake to arrive at your own location.

The new ShakeAlert is to be tested on the coast of Chile

"30 years ago it took months to compile a rough picture of the deformations of an earthquake," says the seismologist and co-author of the study Thomas Heaton. "The new technology promises to deliver an almost instantaneous image with a much higher resolution." The American Agency for International Development now wants to finance a pilot project in which ShakeAlert will be tested simultaneously with scientific sensors on the coast of Chile.

The German engineer Jürgen Przybylak has also developed an early warning system that strikes 30 seconds before the actual earthquake. It detects the first waves in the ground and immediately closes supply networks in order to prevent major damage caused by escaping gas, for example.

A contribution by:

  • Gudrun von Schoenebeck

    Gudrun von Schoenebeck has been a journalist in print and online media since 2001. In addition to architecture, art and design, she has above all opened up the exciting field of space travel.