I think the governor of California exaggerated the capabilities of the new ShakeAlert system. See California launches earthquake early warning app [Note: Someone please tell the mayor of Oakland that you would only "Drop, cover and roll" if you were on fire in an earthquake]. The governor encouraged "millions" to sign-up for the new ShakeAlert app, and I may be stupid, but the only "sign-up" page I found was this one for Los Angeles.
Here's the deal. For all surface fault earthquakes, the amount of warning time will be measured in seconds, not minutes. I do not think that our existing network of cellular phone/wireless providers have the capacity to do millions of notifications in a matter of seconds. Perhaps with the future fielding of 5G, that capacity might be enabled — but I don't think it will work today.
From this story, Earthquakes Still Surprise Us, Even with All the Science.
I copied this paragraph: "The plan, once all 1,675 seismic sensors have been installed in the early 2020s [my highlight], is to be able to send warnings to every smartphone, business, public agency, utility and home where shaking is predicted in California, Oregon and Washington. The alerts, sent out a few seconds to a minute before the shaking starts, would automatically brake trains, open firehouse doors, close valves in fuel pipelines and halt elevators at the nearest floor."
You get the impact? They system is not fully operational and it will be "years" before it is totally functional. Go back and listen to the governor's remarks. Millions notified? Millions should sign up "now"?
As I've written about previously, we should be concentrating on the machine to machine (M2M) signals described above in italics, that will provide for instantaneous reaction electrically and mechanically. Warning people should be secondary — at this point.
Last, California will be the first to implement such a system. While Washington state and Oregon are both in the network, the penetration of strong motion sensors is pitiful when compared to California. The accuracy and computations will therefore be constrained until — right after the next big earthquake that kills people — funding is allocated to build out and maintain the system.
Deaths are a great motivator for state and local politicians. We did something!
