Faculty of Science and Technology

Scientists at Lancaster University working to learn more about the origin of rogue waves in the ocean have learnt that reverse energy flows can cause the phenomenon to happen in the lab. It is the first explanation of giant ocean waves, which could be responsible for many unexplained losses of large ships, to have been successfully tested.

The experiments, funded by the EPSRC, use superfluid helium to exactly mimic how waves naturally behave.

There is intense interest in the origin of giant waves on account of the commercial importance of this extraordinary phenomenon which has been photographed and can be detected and tracked from satellites. Survivors describe a giant wave as being like "a wall of water", perhaps 100 feet or more or more in height.

The results of the experiments astonished the team who discovered that, given the right conditions, wave energy could sometimes flow in the reverse direction leading to production of giant waves in their laboratory. The experiments show that, most of the time, there is a continuous flow of energy towards shorter and shorter wavelengths until, eventually, the resultant tiny "ripples" get destroyed. But exactly the opposite effect can sometimes happen.

The work was carried out by Professor Peter McClintock , Dr Andrei Ganshyn and Dr Victor Efimov in Lancaster University's Physics Department, with collaborators at the Institute of Solid State Physics in Chernogolovka, near Moscow, where much of the preliminary work was carried out.

Their results have been published in Physical Review Letters.

The team are planning more experiments in Lancaster in tandem with the theoretical studies, to further understand the conditions needed to create giant waves.

Fri 05 September 2008

Associated Links

• Observation of an Inverse Energy Cascade in Developed Acoustic Turbulence in Superfluid Helium - published in Physical Review of Letters, August 2008