GeoNet New Zealand Tsunami Warning System
The Ministry of Civil Defence and Emergency Management of New Zealand (MCDEM) uses seismic sensors able to characterise potential tsunami-generating earthquakes occurring off the country's coast. It also operates or shares tsunami gauges across the greater New Zealand region to observe any tsunamis that may have been generated.
The New Zealand seismograph network includes long-period seismic sensors which are able to detect potential tsunami-generating earthquakes occurring off the New Zealand coast. Analysis of the seismic waves can determine whether the event is likely to have disturbed the sea floor and caused a tsunami, allowing warnings to be issued by civil agencies. Such warnings will frequently come too late for people on the affected coast, but they will still be timely alerts for the initiation of any emergency response.
MCDEM is responsible for the dissemination of national official tsunami notifications in New Zealand. With technical support from GNS Science, MCDEM assesses all messages received from the Pacific Tsunami Warning Center (PTWC, based in Honolulu, Hawaii) to determine the threat for New Zealand. Official tsunami notifications for New Zealand are disseminated by MCDEM via the National Warning System on a 24/7 basis.