In early 2021, the National Oceanography Centre enhanced their existing research ships with two RS Aqua WaveRadar REX2 systems, for the RRS Discovery and the RRS James Cook. The RRS Discovery is now equipped with a full REX2 system, while the RRS James Cook REX2 system will be installed later in the year during routine maintenance.
The NOC’s research vessels are multidisciplinary ships, specifically designed for the challenges of 21st century oceanography. Both ships are fitted with state-of-the-art, high-performing instruments and equipment. Combined they are the UK’s primary vessels for oceanographic observation.
Application
The capabilities of the REX2 sensor system were chosen by the NOC to provide accurate sea state intelligence during the ships’ operations such as offboard equipment handling (ROV operations and large profiling payloads etc.) and to provide absolute wave height data and so greater accuracy of real time sea state whilst underway.
Both research vessels have X-band radar systems installed to provide surface wave, current and sea state measurement to the NOC’s research community and also enhance safety at sea and to provide navigational intelligence. Whilst X-band systems provide sea state intelligence from radar imagery over a relatively large spatial scale (several kms from the ship), the wave and sea state data close to the ship is often of lower quality than required for ship operations.
WaveRadar REX2 is a downward-facing microwave radar system that delivers exceptionally high-quality wave parameters in the immediate vicinity of the ship. REX2 has been installed on both vessels to enable the scientific engineering team to ground-truth or validate specifically wave height data for the X-band system whenever the ship is sailing.
Furthermore, the wave and sea state intelligence from REX2 will be used whenever the research vessels are carrying out research operations, for instance the deployment of tethered ROV systems or other large and valuable offboard systems.
When the vessel deploys these offboard systems, often the ship will be holding position dynamically and is vulnerable to the prevailing wave climate and other features such as rogue waves. REX2 provides direct measurement of ocean waves in the immediate vicinity of the ships in real time, providing reliable wave intelligence to the bridge, to the scientific engineering teams, and to any stakeholder with secure internet access to the ship.
REX² Technology
The full REX2 system, inclusive of real-time motion-compensated wave processing suite – WaveView Connect – and a bespoke mounting frame, is built for the harsh environment of the open ocean and is ideal for the RRS Discovery and the RRS James Cook’s scientific expeditions. With end users from almost every continent operating in every Ocean, internationally recognised hazardous zone certifications and high-level commissioning support from RS Aqua, WaveRadar REX2 can be used in almost any location around the world.
Coupled with WaveView Connect, REX² is able to deliver motion compensated wave measurements in real time. The GR-2 mounting frame is specifically designed for the WaveRadar REX². It is designed to provide an extremely stable, rigid platform that complements the high performance of the REX².
Conclusion
These two use cases of the REX2 data – ground-truthing X-band data and real time wave climate observation during ship operations – enable the ship operators and the scientific engineering team to have greater confidence in their understanding of the wave climate in open ocean conditions, whilst also optimising their operations. The end result is an expansion and improvement of the essential ocean variables provided to the oceanographic science community and more efficient and safer work environment at sea.
