The New Zealand Deep-Ocean Assessment and Reporting on Tsunami (DART) network is distributed across the southwestern Pacific Ocean to support detection and analysis of potential tsunami in the Pacific, with a specific focus on the Hikurangi, Kermadec, Tonga, and Vanuatu (formerly New Hebrides) trenches. The twelve DART sensors deployed currently help us monitor tsunami by recording pressure created by the water column above the sensor and detecting anomalously high or low changes in that pressure as waves move through the water column. Each DART sensor consists of an ocean bottom pressure sensor which record the pressure of the water above the sensor on the seafloor and surface buoys which transmit that data via satellite transmission to GNS Science and on to global and regional monitoring partners. The data helps scientists provide advice on whether a tsunami has been generated or not, and more accurately estimate how big the waves could be if they reach our coast and when they might reach us. You can read more about the Tsunami monitoring and detection network here.
Data from DART sensors are sampled every 15 minutes when sea conditions are normal, however if a sensor detects a significant change in water pressure the DART will be triggered into 'event mode' and start sampling data every 15 seconds. DARTs can also be triggered manually by the National Geohazards Monitoring Centre (NGMC) / Te Puna Mōrearea i te Rū.
The sampling rates are represented on the graph with different coloured lines and are referred to in the legend. The legend is shown above in the time series graph in the following format “Monitoring - 15m” indicating when sea conditions are normal and “Triggered - 15s" indicating when a sensor has been triggered into 'event mode'.
If you want to download data or explore more DART or other data types, try our Data Exploration Tool.
Learn about how the NZ DART network monitors changes in sea level.