LÉ Niamh to track sea wave activity for research project

The Naval Service patrol ship LÉ Niamh is not only rescuing refugees in the Mediterranean. It is also gathering information for a marine research project which could make life a lot easier for international shipping.

Months before the ship was deployed to take over from the LÉ Eithne on humanitarian rescue, it was fitted with ultrasonic sensor equipment on its bow which measures sea states.

The project run by NUI Galway (NUIG) has been funded by Enterprise Ireland and aims to develop technology which can determine the elevation of the ocean surface as it changes due to wave motion.

This in turn could make for quicker, safer sea journeys, with less turbulence, and could prove valuable for shipping companies, weather forecasting and other offshore activities, according to Dr Brian Ward of NUIG's AirSea Lab.

Dynamic

The ocean surface is a dynamic environment where conditions can change quickly.

Technology developed by NUIG’s AirSea Lab at NUIG and fitted on the Naval Service patrol ship is collecting data which can be compared with wave measurements mounted on buoys at sea.

“This will help to develop sophisticated algorithms to compute the wave spectra,” Dr Ward said.

The measurements are collected whenever the ship leaves port, and in no way interfere with its humanitarian work. The fact that it can provide information from both the Atlantic and Mediterranean is of additional value to the project.

Dr Ward is heading to sea himself this week to carry out work on a separate experiment which aims to track oil spills.

The project is funded by the Norwegian Research Council in collaboration with scientists from the Norwegian Meteorological Institute and the University of Oslo.

As Dr Ward explains, oil spills at sea do not follow tracks predicted in existing sea forecasting models.

“Oil changes the physics of the ocean surface, and virtually shuts down wave activity – hence the saying ‘pouring oil on troubled waters’,” he said.

Heavy weather

Aran island currach fishermen used to take cans of oil with them in case they encountered heavy conditions, and this principle is being applied by Dr Ward’s research team.

He and his Norwegian colleagues have hired the Tarrea Queen angling boat in Galway, and will use it to deploy instruments to measure turbulence, waves and air-sea momentum transfer in Galway Bay.

His team has devised a profiling instrument known as an air-sea interaction profiler which will be deployed each day.

“We will then pour a very small quantity of cod-liver oil into its path, which will provide a record of the turbulence both inside and outside the oil patch,” he said.

“At the same time, the instruments on the boat will measure the dampening of the waves from the oil.”

Earlier this year, Dr Ward and the Norwegian team travelled north to Svalbard to conduct related experiments on ice, measuring the “dampening” of waves at the ice-water interface.