EewcartoonWhat would you do with a few seconds or minutes of warning before an earthquake strikes?

Starting next week, a few businesses and agencies will start testing an earthquake warning system prototype that can provide alerts seconds or minutes before the ground shakes. These companies including Boeing, Alaska Airlines and Intel will be able to work with the system and figure out how to make use of warning times so slight they seem at first like a joke.

But earthquake early warning has proved its worth in countries like Japan, where alerts are blasted out to the general public via cellphone, bullet trains automatically coast to a stop and manufacturing plants are hard-wired to shut down.

The approach is based on the fact that the first vibrations produced when a fault ruptures zip through the ground at blazing speeds but generally don’t cause much damage. By detecting those initial signals, the system can sound an alert before the strongest shaking arrives.

For nearby quakes, there’s not much benefit. But for more distant quakes, the time lag can be 30 seconds or more.

In the case of a major quake on the offshore fault called the Cascadia Subduction Zone, Seattle and Portland could get as long as three or four minutes’ notice before the ground starts heaving.

Tests of a prototype early-warning system called ShakeAlert have been under way in California for several years. The UW is part of a consortium working to expand the network to cover the entire West Coast, at a cost of about $16 million a year.

Businesses are already springing up in California to help companies and agencies integrate earthquake alerts into their systems.