New Directions in Real-time Earthquake Characterization and Early Warning Damage Prediction at Different Scales

Rapid urbanisation, the interconnection of economies and growing dependence on technology makes modern society increasingly vulnerable to natural disasters. In case of earthquakes, the mitigation of seismic risk in urban and industrial area can be effectively accomplished by Earthquake Early Warning systems (EEWS), which performs real-time event detection and characterization, issues rapid alerts, and thus, allow both to protect the population and reduce the vulnerability of civil and industrial structures, as well as industrial machineries, by starting automatic security procedures. This work provides an overview of some significant advancement achieved during the last years in the research field of EEWS, which focus on the early warning damage prediction at different scales. In particular, we cover an ideal path from large scale seismological towards site-specific structuralengineering EEWS applications. The first part is dedicated to the review of the real-time procedure proposed by Zollo et al. (2010) for the early warning P-waves driven prediction at regional scale of the Potential Damaged Zone (PDZ). The method is implemented in the PRESTo system (PRobabilistic and Evolutionary early warning SysTem), a highly configurable and easily portable platform for Earthquake Early Warning developed by the RISSC-Lab of the Department of Physics at the University of Naples ‘Federico II’. It combines a regional and an on-site approach and exploits the characteristic P-waves period (τc) and the peak displacement (Pd) measured on the initial P-wave signal at each station, which then are compared with threshold values previously established through an empirical regression analysis, and delivers an alert level at each station correlated with the expected local damage. Therefore, integrating the measured on-site parameters at stations (Pd, τc) and the estimated regional parameters (hypocenter), PRESTo can identify the damage area in a few seconds after the event origin with a good matching with the instrumental intensity maps produced much later. PRESTO is currently under evaluation at the ISNET network (Italy), as well as other international site (e.g. South Korea, Spain, Romania). The second part of the work aims at presenting a first attempt to design an early warning and rapid response procedure for real-time risk assessment at the scale of a metropolitan area (Picozzi et al. 2013). In particular, the procedure uses the typical real-time information (i.e. P-wave time arrivals and early waveforms) coming from a regional seismic network for locating and evaluating the size of