First, Twitter: While the Survey already has a user-driven website titled "Did You Feel It," the advantage of tracking reports via Twitter feeds is speed: Researchers can almost instantly get a sense of the size and scope of an earthquake -- and even assess whether or not there's associated damage -- with the instant info stream that is Twitter. Normal earthquake analysis -- size, location -- can take up to 20 minutes in sparsely populated areas, scientists say.
The USGS is calling it TED, or Twitter Earthquake Detection. The program would collect tweets about a particular event and show a location, map and reports almost instantaneously. USGS scientist Paul Earle calls the resulting product a "Twitter-enhanced alert."
USGS officials say that even in California, where earthquake monitoring equipment is bountiful, it can take up to three minutes to collect, analyze and put out data about a quake the traditional way. In less populated parts of the U.S., which often have fewer earthquake monitoring stations, such reports can take as long as 20 minutes to publish, said USGS scientist Michelle Guy. Twitter could crush that time into seconds. "Comparatively people start tweeting about an event within seconds after in occurs," Guy said.
"After an earthquake they [Twitter users] often rapidly report that an earthquake has occurred and describe what they experienced," adds Earle. " ... Twitter reports often precede the USGS' publicly released, scientifically verified earthquake alerts."
Regarding the warning system: It's coming to California, says the USGS. "The California Integrated Seismic Network (CISN) ShakeAlert System, will provide warning to a small group of test users, including emergency response groups, utilities, and transportation agencies," states the Survey. "While in the testing phase, the system will not provide public alerts."
It is feasible that in the future, however, the warning system would allow information to be broadcast online and on television, and via text message and email; and it could trigger electronic systems to stop elevators at the nearest floor in high-rises, and slow and halt trains.
Electronic communication, the USGS notes, is faster than the speed of earthquakes, so first rumbles could lead to rapid warnings throughout a region like Southern California.