Progress of the earthquake early warning system in Fujian, China

In this article, we systematically introduce the atest progress of the earthquake early warning （EEW） ;ystem in Fujian, China. We focus on the following key echnologies and methods： continuous earthquake location md its error evaluation; magnitude estimation; reliability udgment of EEW system information; use of doubleparameter principle in EEW system information release hreshold; real-time estimation of seismic intensity and available time for target areas; seismic-monitoring network and data sharing platform; EEW system information ; elease and receiving platform; software test platform; and est results statistical analysis. Based on strong ground notion data received in the mainshock of the Wenchuan earthquake, the EEW system developed by the above algorithm is simulated online, and the results show that the ;ystem can reduce earthquake hazards effectively. In lddition, we analyzed four earthquake cases with magniude greater than 5.5 processed by our EEW system since he online-testing that was started one year ago, and results ndicate that our system can effectively reduce earthquake lazards and have high practical significance.

Probabilistic earthquake early warning times in Fujian Province

Earthquake early warning （EEW） systems are a new and effective way to mitigate the damage associated with earthquakes. A prototype EEW system is currently being constructed in the Fujian Province, a region along the Southeast coast of China. It is anticipated that the system will be completed in time to be tested at the end of this year （2013）. In order to evaluate how much advanced warning the EEW system will be able to provide different cities in Fujian, we established an EEW information release scheme based on the seismic monitoring stations distributed in the region. Based on this scheme, we selected 71 historical earthquakes. We then obtained the delineation of the region＇s potential seismic source data in order to estimate the highest potential seismic intensities for each city as well as the EEW system warning times. For most of the Fujian Province, EEW alarms would sound several seconds prior to the arrival of the destructive wave. This window of time gives city inhabitants the opportunity to take protective measures before the full intensity of the earthquake strikes.