A Review on the Development of Earthquake Warning System Using Low-Cost Sensors in Taiwan

Area of Science:

• Earthquake Engineering
• Seismology
• Disaster Risk Reduction

Background:

• Taiwan's Central Weather Bureau (CWB) operates a regional earthquake early warning (EEW) system.
• The National Taiwan University (NTU) deployed the low-cost micro-electro-mechanical system (MEMS)-based P-Alert EEW system in Taiwan since 2010.
• The P-Alert system is vital for on-site warnings and generating real-time shakemaps.

Purpose of the Study:

• To evaluate the effectiveness of the P-Alert system for on-site earthquake early warnings.
• To assess the utility of P-Alert generated shakemaps for damage assessment and risk mitigation.
• To highlight the advancements in P-Alert instrumentation and its expanding deployment.

Main Methods:

• Utilizing real-time seismic signals from P-Alert instruments for immediate warnings.
• Generating various types of shakemaps, including peak ground acceleration (PGA), peak ground velocity (PGV), spectral acceleration (Sa), and CWB intensity maps.
• Analyzing seismic data for structural health monitoring and co-seismic deformation estimation.

Main Results:

• The P-Alert system provides 2-8 seconds of warning time for areas within the CWB regional system's blind zone.
• Peak ground velocity (PGV) has been identified as a more effective indicator of earthquake damage than peak ground acceleration (PGA).
• The P-Alert network's successful performance has led to its expansion in Asia-Pacific countries.

Conclusions:

• The P-Alert system significantly enhances earthquake preparedness and response capabilities through reliable on-site warnings.
• Advanced shakemap products derived from P-Alert data improve the accuracy of damage assessment and inform disaster relief efforts.
• The widespread adoption of P-Alert instrumentation underscores its value in seismic risk reduction globally.