Earthquake early warning
Under earthquake early warning ( Jap. 緊急地震速報 , kinkyū jishin sokuhō ) refers to an in Japan used system the Japan Meteorological Agency informed about potential risks (JMA) that immediately after the occurrence of significant shocks in seismically active zones affected areas. For all potentially affected areas, warning messages about vibrations are broadcast via television , radio or their own receivers, so that the population can prepare for the approaching earthquake within a few seconds if possible.
In addition to the JMA earthquake early warning system, there are other systems, including the UrEDAS from Tetsudō Sōken of the former state railway in Japan for today's Japan Railways companies or the Sistema de Alerta Sísmica (SAS) in Mexico City or QuakeGuard in some regions of the United States.
Installation
On October 1, 2007, the JMA established the system for the public and disseminated information on what to do if the warnings occurred. It should be noted that a warning can typically only be given a few seconds to a maximum of a few ten seconds before the first local vibrations; the areas in close proximity to the epicenter can be shaken even before the warnings are received.
The early warning time depends on the distance between the affected region and the earthquake center. Seismic waves propagate at different speeds, primary waves faster than the more dangerous secondary waves .
The system is using the tsunami - early warning system linked in Japan.
Use
In addition to personal protection, which the person warned can immediately create themselves, the system should also enable machine operators to minimize the risk of serious damage to people and property. For example, bus and train drivers as well as motorists reduce their speed, educators and supervisors instruct and inform trusted persons. Risky work, such as operations, as well as heavy machinery can in the best case be stopped and interrupted.
Web links
- Earthquake Early Warnings (EEW) website - Japanese and English
- Information sheet (PDF; 1.1 MB) - Japanese and English