Progress on Development of an Earthquake Early Warning System Using Low-Cost Sensors

Taiwan is one of the leading developers of earthquake early warning (EEW) systems. The Central Weather Bureau has been the primary developer of the EEW system in Taiwan since 1993. In 2010, the National Taiwan University (NTU) developed an EEW system for research purposes using low-cost accelerometers. As of 2014, a total of 506 stations have been deployed and configured. The NTU system can provide earthquake information within 15 s of an earthquake occurrence. Thus, this system may provide early warnings for cities located more than 50 km from the epicenter. Additionally, the NTU system also has an onsite alert function that triggers a warning for incoming P-waves greater than a certain magnitude threshold, thus providing a 2-3 s lead time before peak ground acceleration for regions close to an epicenter. Detailed shaking maps are produced by the NTU system within one or two minutes after an earthquake. Regions of high shaking indicated by the shalking map can indicate locations of damage and casualties and help estimate the damage incurred. The direction of earthquake ruptures are also potentially identified based on detailed shaking maps and strong motion records of the NTU system.