Collecting valuable wave data to support the RNZN’s deployments to the Ross Sea

"We are now seeing high quality wave measurements coming in from some of the remotest locations on Earth."

  • HMNZS OTAGO deployed the moored wave buoy TRIAXYS in the southernmost location a wave buoy has ever been moored.
  • Five free floating buoys provided by SCRIPPS Institution of Oceanography were also deployed to collect wave height data short term.
  • TRIAXYScollected 170 days of good quality data including a massive 19.4 metre wave.

The Royal New Zealand Navy (RNZN) deploys annually to the Ross Sea to complete fishing boat inspections on behalf of the New Zealand Government’s commitment to the Convention on the Conservation of Antarctic Marine Living Resources.

Extreme weather and rough seas make the Ross Sea and Southern Ocean difficult to work in. Reliable ocean and atmospheric measurements are required to provide an understanding of the region, to support current and future operations.

Southern Ocean Wave Buoy TRIAXYS™

On 8 February 2017, the HMNZS OTAGO launched a moored wave buoy called TRIAXYSabout 11 km south of the remote Campbell Island. By collecting precise wave spectral data as well as wave height and wave direction TRIAXYS has helped to:

  • increase safety through better forecasts
  • enable better ship design, based on understanding of the sea state.

The buoy remained in place for about 6 months until the mooring line broke due to wear and tear in the continuously rough seas. It continues to send us very valuable data while drifting its way towards Chile. 

MooredLocation

The moored location of the wave buoy TRIAXYS.

Update

In collaboration with MetOcean Solutions and the NZDF we supported another wave buoy deployment at Campbell Island in March 2018. The mooring design was modified so that it will cope better with the harsh conditions and it reduces the risk of mooring failure before the buoy’s scheduled maintenance in the summer season.

Conclusions

Considerable knowledge gaps in our understanding of the Ross Sea and Southern Ocean environment limit our ability to design and operate ships in the region. The development of collaborative programmes such as the Southern Ocean wave buoys programme enables the NZDF to increase the safety and efficiency of operations while allowing New Zealand science organisations to complete work they could not have otherwise achieved.

All data from the wave buoys is openly available for research. Read more about the Southern Ocean wave buoys and the data they are sending back on the MetOcean Solutions website.