Rapid Earthquake Early Warning (REWS) in Romania: Application in Real Time for Governmental Authority and Critical Infrastructures

Abstract

In Romania, there is an operational early warning system that is able to send earthquake location and magnitude since 2013. Romanian territory, together with the neighbor countries Moldova, Ukraine and Bulgaria, are periodically affected by the intermediate depth earthquakes originating from Vrancea area. In order to rapidly locate and estimate magnitude are used a few seconds of strong motion acceleration data. The alert notification broadcasting to users uses an internal communication network built on redundant links with a very high availability. When an earthquake is detected at the surface by the 24 bits accelerometers and velocity sensors, the digital seismic data is sent in real time to the National Institute for Earth Physics where the first 4 s of data are analyzed and alert is issued. The alert is sent to the users using TCP/IP or UDP communication protocols. At the emergency response units there are computers and dedicated devices that have three levels of warning according to the magnitude of the earthquake. Warning levels are associated to different management systems of strategic facilities than can block or enable automatically chosen activities of those facilities. The REWS is sending alerts also to civil protection and Koslodui power plant, in the northern part of Bulgaria. Since the REWS is able to rapidly locate events and compute magnitude, there were no false alerts recorded and were issued 19 earthquake alerts for earthquakes with M > 4.0.