Christchurch plans to replace most tsunami sirens with mobile alerts due to confusion over siren use.

Christchurch may reduce its tsunami sirens from 45 to just four due to a review finding that they cause confusion and delays. The city will consider using emergency mobile alerts as the primary warning system, with television, radio, websites, and social media as secondary methods. The review noted concerns that sirens could be misinterpreted and create a false sense of security, while mobile alerts are seen as clearer and more effective.