Benefits and Costs of Earthquake Early Warning

Abstract

Earthquake early warning (EEW) is the rapid detection of earthquakes underway and the alerting of people and infrastructure in harms way. Public warning systems are now operational in Mexico and Japan, and smaller-scale systems deliver alerts to specific users in Turkey, Taiwan, China, Romania, and the United States. The warnings can arrive seconds to minutes before strong shaking, and a review of early warning applications around the world shows this time can be used to reduce the impact of an earthquake by many sectors of society. Individuals can use the alert time to drop, cover, and hold on, reducing injuries and fatalities, or if alert time allows, evacuate hazardous buildings. Train derailments can be reduced, chemical splits limited, patients in hospitals protected, fire ignitions prevented; workers in hazardous environments protected from fall/pinch hazards, reducing head injuries and/or death. It is impossible to complete an exhaustive list of applications and savings generated by a warning system in the United States, but the benefits clearly outweigh the costs. Three lives saved, two semiconductor plants warned, one Bay Area Rapid Transit train slowed, a 1% reduction in nonfatal injuries, and a 0.25% avoidance of gas-related fire damage would each save enough money to pay for 1 year of operation of a public warning system for the entire U.S. West Coast. EEW could also reduce the number of injuries in earthquakes by more than 50%.

How “good” are real‐time ground motion predictions from Earthquake Early Warning systems?

“…The main goal of Earthquake Early Warning (EEW) systems is to detect ongoing earthquakes in real time and to provide information about the earthquake to target sites before they are hit by strong ground motion [ Heaton , ]. If such real‐time alerts are timely and sufficiently accurate, they allow EEW end users to trigger a wide range of protective emergency actions that can greatly reduce earthquake damage [e.g., Strauss and Allen , ]. Operating EEW systems have already provided useful public warnings during several large earthquakes, including the 2016 M w 7.0 Kumamoto, Japan [ Kodera et al ., ], the 2011 M w 9.0 Tohoku, Japan [ Fujinawa and Noda , ], and the 2012 M w 7.4 Oxaca, Mexico, earthquakes [ Cuéllar et al ., ].…”

Earthquake Early Warning ShakeAlert System: West Coast Wide Production Prototype

“…4). Another example is MyEEW, a cell phone app developed by Berkeley Seismological Lab (Strauss and Allen, 2016). Other message formats are being developed to allow for flexible integration into mobile phone and other mass-distribution alert applications, engineering applications, and other uses.…”

“…The ANSS is a federation of USGS-supported seismic networks that delivers real-time earthquake information for the nation (USGS, 1999). EEWs have the potential to give people and systems the necessary time to conduct preemptive protective actions such as automatically slowing trains, opening fire station doors, and sending elevators to the nearest floor, in preparation for impending ground shaking (Strauss and Allen, 2016). Alerts associated with aftershocks after a large earthquake may also provide useful decision-making information about whether or not to temporarily suspend rescue and repair operations (Bakun et al, 1994).…”

Earthquake Early Warning and Beyond

“…The recent development of Earthquake Early Warning (EEW) systems provides at least one way to identify the occurrence of an earthquake in near real-time and issue a warning to the public [1]. The effectiveness of EEW has been proved in various regions over the past decade by reducing fatalities, injuries, and damage caused by earthquakes, by alerting people to take cover, slowing down and stopping trains, opening elevator doors, and many other applications [22]. The concept of EEW is simple -seismic waves generated by earthquakes travel at the speed of sound, while electronic signals travel at the speed of light (analogous to seeing lightning before hearing the sound of thunder).…”