Program uses Singapore Time and is 8 hours ahead of GMT
Using low-cost sensors to build a seismic network for earthquake early warning (EEW) and to generate shakemaps is a cost-effective way in the field of seismology. The National Taiwan University (NTU) network employing 760 P-Alert low-cost sensors based on micro-electro-mechanical systems technology is operational for almost the last 10 years in Taiwan. This instrumentation is capable of recording the strong ground motions of up to ± 2g and is dense enough to record the near-field ground motion. The NTU system has shown its importance during various earthquakes that caused damage in Taiwan. Although the system is capable of acting as a regional as well as an on-site warning system. However, it is particularly useful for on-site warning. Using real-time seismic signals, each P-Alert device can provide a 2–8 second warning time for the earthquake source regions situated in the blind zone of the Central Weather Bureau (CWB) regional EEW system during 2016 Mw6.4 Meinong and 2018 Mw6.4 Hualien earthquakes. The CWB is the official agency for issuing national wide warning in Taiwan. The shakemaps plotted by the P-Alert dense network help to assess the damage pattern and rupture directivity, key features in the risk mitigation process. These shakemaps are delivered to the intended users, including the disaster mitigation authorities, for possible relief purposes. Currently, the P-Alert network can provide peak ground acceleration (PGA), peak ground velocity (PGV), spectral acceleration (S_a) at different periods, and CWB intensity shakemaps. The PGA and PGV shakemaps plotted using this network have proven helpful in establishing the fact that PGV is a better indicator of damage detection than PGA experience from two earthquakes occurred in the Hualien area of Taiwan in 2018 and 2019. The 2018 earthquake had a magnitude ML6.2 reported by the CWB produced severe destruction; however, the 2019 earthquake (ML=6.3) did not cause any severe damage. The P-Alert device is also useful in structural health-monitoring and estimating co-seismic deformations. Encouraged by the performance of the P-Alert network, more instruments are installed in Asia-Pacific countries.
Professor Wu works in the fields of earthquake early warning, real-time seismology, and seismotectonics. In the past few decades, he has established as one of the leading figures in earthquake early warning. He received his Ph.D. in Geophysics from National Central University, Taiwan in 1999. After working for Central Weather Bureau as research fellow, he accepted a faculty position at National Taiwan University (NTU) in 2004. He was promoted to Professor in 2010 and to Distinguished Professor in 2012. In addition, he was visiting Scientist of Caltech (2006- 2007), jointed research fellow of National Center for Research on Earthquake Engineering (NCREE, 2014-2017), chair of Taiwan Geophysics Association (2016-2018), chair of Geosciences (NTU, 2016-2020), chair of The Geological Society located in Taipei (2017-2019), and associate editor of Terr. Atmos. Ocean. Sci. (TAO, 2009-2015). Now, he is Jointed Research Fellow of Academia Sinica (Institute of Earth Sciences, 2017-) and member of the editorial board of Earth, Planets and Space (EPS, 2015-), Scientific Reports (2019-), Sensors (2021-), and Vietnam journal of Earth Sciences (2015-). He was invited to participate the Europe Framework Program (FP6 &FP7) projects to develop the earthquake early warning systems for Europe cities (2006-2014). Nowadays, he tries to share his knowledge and assist other countries (India, Indonesia, China, Korea, Vietnam, Nepal, and Bhutan) to build up their earthquake early warning system using low-cost sensors.
Yih-Min WU
Department of Geosciences,
National Taiwan University
Institute of Earth Sciences,
Academia Sinica