« on: May 19, 2015, 10:53:33 AM »
An earthquake early warning (EEW) can save many lives, but unfortunately it’s an extremely expensive system for some countries. A group of scientists believe that smartphones could do the same work and at a much more affordable cost.
The research done at the U.S. Geological Survey in Pasadena, published in Science Advances says that a network of phones can replace the seismographs, by turning into a crowdsourced early earthquake warning that could help notify communities nearby that an earthquake is coming their way. The study analyzed historical data of earthquakes using a Nexus 5 and found that the GPS of modern smartphones are more powerful than you’d think.
“The GPS on a smartphone is shockingly good,” said study leader Sarah Minson. “If you take your phone and move it six inches to the right, it knows with surprising accuracy that it moved six inches to the right — and that is exactly what we want to know when studying earthquakes.”
Current warning systems capture the first tremors of an earthquake, estimating where the epicenter of the quake is located and what its intensity is. However, the method is very expensive and most developing countries still cannot afford to install them. The new system using smartphones may not be as accurate, but costs much less.
Modern phones are equipped with GPS sensors and accelerometers, which turn out to be very useful as a seismic sensor. A single smartphone would not be very useful, but a network of them can generate sufficiently accurate information about the earthquake.
With millions of smartphones in the proximities of an earthquake, the researchers hope that there are at least a few thousands of them able to function as earthquakes sensors. Even with imprecise GPS sensors, they are sensitive enough to detect the earliest signs of quakes that are magnitude 7 and stronger.
The challenge right now is to distinguish an earthquake tremor from the movements of a smartphone in a person’s pocket, for example. The scientists hope to overcome this problem by only registering an earthquake if at least 100 phones record the same amount of displacement at the same time and in the same area.
The staff of the US Geological Survey should get a system pilot project in Chile, installing it on new smartphones sold in the country, which doesn’t have an earthquake warning system. “The cost is essentially zero, especially since people buy new phones every two years or so to have the latest-and-greatest model,” Minson said.
Source: Science Advances
“Allahumma inni as'aluka 'Ilman naafi'an, wa rizqan tayyiban, wa 'amalan mutaqabbalan”
O Allah! I ask You for knowledge that is of benefit, a good provision and deeds that will be accepted. [Ibne Majah & Others]
Dept. of ETE, FE