J-Alert

J-Alert (全国瞬時警報システム, Zenkoku Shunji Keihō System^?) is a nationwide warning system in Japan launched in February 2007. It is designed to quickly inform the public of various threats. The system was developed in the hope that early warnings would speed up evacuation times and help coordinate emergency response.

J-Alert is a satellite based system that allows authorities to quickly broadcast alerts to local media and to citizens directly via a system of loudspeakers. According to Japanese officials it takes about 1 second to inform local officials, and between 4 and 20 seconds to relay the message to citizens.

All warnings, except for severe weather warnings, are broadcast in five languages: Japanese, English, Mandarin, Korean and Portuguese (Japan has a small Chinese, Korean and Brazilian population). The warnings were broadcast in these languages during the 11 March 2011 earthquake and tsunami. The severe weather warnings are only broadcast in Japanese.

J-Alert broadcasts via the Superbird-B2 communication satellite.

Many prefectures and urban areas have been slow in adopting the system. Upon its introduction, the Japanese government hoped to have 80% of the country equipped with the J-Alert system by 2009. However, under current plans, by 2011 only 36% of the nation has been covered. Cost has been a major factor. The initial installation is estimated to be around 430 million yen, and the yearly maintenance is estimated to be around 10 million yen. Local governments have been hesitant to cut other services to implement the system.

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Wikipedia