Earthquake warning system offers 20-second notice

Californians enjoy lovely weather year-around, but the possibility of an earthquake always hovers.

The quakes can't be prevented, but a U.C. Berkeley seismologist wants to create a warning system that sends Californians alerts just before an earthquake hits.

Richard Allen, a professor of earth-sciences at Berkeley has developed a system that can send you an alert through your cellphone or laptop, about 20 seconds before an earthquake begins.

Allen's product, called , detects the first energy to radiate from an earthquake, called the P-wave energy. This wave usually doesn't cause any damage. By using the arrival time of the P-wave, ElarmS algorithms calculate the location and magnitude of the quake.

Although 20 seconds might seem like very little time, it's enough to get under cover. It's also enough time to warn fire stations, ambulances and hospitals.

ElarmS is currently being tested by the , a partnership among federal, state and university agencies involved in California earthquake monitoring