AT&T, Qualcomm See Promises, Challenges in Mobile Earthquake Early Warning Systems

Mark Johnson, earthquake and tsunami preparedness program branch chief for the California Office of Emergency Services, said the state legislature tasked his office with developing a comprehensive statewide early warning system to provide notice of a coming earthquake "tens of seconds before the shaking occurs." The system, which Johnson and others said is still years away from implementation, will measure the time and distance between the initial shockwave -- known as the P wave -- and the second, and typically most destructive shockwave -- called the S wave -- to determine the amount of time before the S wave hits certain high-density areas. It will then broadcast a short warning using cell towers and mobile technology to cellphones. The anticipated time it will take to broadcast the message to mobile devices from the initial receipt of P wave readings, Johnson said, is 20 seconds. The goal is to provide enough advanced warning to move people to safe zones, slow and stop trains and transportation and isolate hazards such as equipment and chemicals, Johnson said.

Implementing the program in California will be challenging, said Johnson, due to several factors, including the large number of fault lines in the state, the small number of large events, limited sensor coverage, missed events due to lack of data reception, and false alarms. He said his office is partnering with the utility, transportation and telecom sectors to work through the anticipated system problems. EEWS will be partly built upon the state's ShakeAlert prototype, which is part of CISN and calculates and displays shaking information, including the anticipated shaking intensity and a real-time countdown until shaking is expected to start.

Brian Daly, AT&T core network and government and regulatory standards director, said ATIS' recently completed early earthquake warning feasibility study identified ways the service could utilize existing cellular networks to transmit the warnings. Daly said the study proposes the notifications should be standardized for existing 4G LTE networks and can be received by new, EEW-enabled cellphones with a valid cellular subscription. The messages will be short and give only essential information, and will be received as "quickly as technically feasible," said Daly. Upon receipt of the P wave information, automated computers will run algorithms to determine the timing of the next wave, as well as the anticipated affected area. Cellular networks will make the best approximation to map the EEWS notification area and send the data to the appropriate cell sites, Daly said.

Farrokh Khatibi, Qualcomm engineering director, said point-to-point communication, such as SMS messaging, isn't fast enough to transmit data in an emergency earthquake situation, and mass SMS messages could bog down the system, resulting in delays. He also said using SMS can jeopardize security, and wouldn't be as effective since it requires a data subscription and not everyone subscribes to a data plan. The proposed system, Khatibi said, allows a commercial mobile service provider to geo-target broadcast systems.

The ATIS study said wireless EEWS notification is "a viable concept" and will work within the constraints of current cellular networks, Daly said. The proposed EEWS will take about three to four years to develop and deploy, he said. Because the system will require new technology to be embedded in cellphones, ATIS estimates it will be five to seven years before a "substantial number" -- more than 25 percent -- of cellular network users will have EEWS capabilities.