Creating a Tsunami Monitoring System for New Zealand
Following the devastating 2004 Indian Ocean tsunami, LINZ and GNS Science began work on establishing a tsunami monitoring system for New Zealand.
A network of pressure sensors measuring sea level at 17 locations will be completed shortly. Most of the sites are along the eastern coastline of the North and South islands with others on Chatham and Raoul islands. The locations were chosen following an assessment of the hazard that tsunami events pose to the country.
The picture below shows work on the installation of the Castlepoint monitoring site.
Data from each site is transmitted in near real time to GNS Science’s GeoNet Project, which is responsible for monitoring geophysical hazards such as earthquakes and tsunami. If a potential tsunami event is identified, GeoNet interprets the information from the monitoring network and provides advice to the Ministry of Civil Defence and Emergency Management who then manage the response that is deemed appropriate.
The data from the monitoring network can be seen on the Geonet website and is also archived and freely available on the LINZ website. The sea level data is referenced to bench marks so it is possible to use the data for other applications.
The network has already successfully recorded a number of tsunami events, fortunately none of which has proved to be devastating or life threatening. The graph below indicates the tsunami waves generated by the Chile earthquake of February 2010 recorded by the monitoring network superimposed on the normal 12 hour tide cycle.
