REAL TIME PERFORMANCE OF THE VRANCEA EARLY WARNING SYSTEM.

An earthquake early warning system (EEWS) is a system that provides rapid notifications before the destructive waves arrives in the target area that has to be warned. EEW systems are used in several countries already: Japan, United States- California, Taiwan, Italy, Turkey and China. Some of them are operational. Some of them are already operational (Japan, Romania, Turkey, Taiwan and California) and some are in testing phase. Most of the EEWS are "regional" (based on a dense network of sensors installed in the earthquake source region) and send the earthquake alert notification to target area located far away from the source. Romanian territory is affected by strong intermediate depth Vrancea events (3 shocks/century with magnitude greater than 7). The recent upgrade of the Romanian Seismic Network (RONET) with strong motion sensors allows recording of strong earthquakes even at small epicentral distance (10-20 km). The Vrancea early warning system sends notifications for events with magnitude larger than 4.5 to 16 early warning receivers at the emergency response units located in Bulgaria and Romania: 7 in Romania at Constanta, Calara?i, Giurgiu, Teleorman, Dolj, Olt and Mehedinti and 9 receivers in Bulgaria, at: Montana, Vidin, Veliko Tarnovo, Ruse, Belene, Dobrich, Kozlodui, Kozlodui 2 and Silistra. Also the earthquake notification is sent to several governmental agencies in Romania. In this paper we present the earthquake early warning system designed for Vrancea area and we analyze its performance. [ABSTRACT FROM AUTHOR]