Australasian Science: Australia's authority on science since 1938

Rogue Wave Theory to Save Ships

A new explanation for rogue waves in the ocean could lead to devices that can warn ships of unforeseen danger.

Rogue ocean waves develop over the course of about a minute and grow to as much as 40 metres in height before disappearing as quickly as they appeared. There are about ten rogue waves in the world’s oceans at any moment. Ships unlucky enough to be where rogue waves appear can capsize or be seriously damaged, as happened in the Mediterranean Sea to the Cypriot ship Louis Majesty, which was struck by a rogue wave in 2010 that left two passengers dead and 14 injured.

“A device on the mast of a ship analysing the surface of the sea could perhaps give a minute’s warning that a rogue wave is developing,” said Prof Nail Akhmediev of The Australian National University.

“Data from buoys and satellites around the world is already being collected and analysed. Combined with observations of the surrounding ocean from the ship, this would give enough information to predict rogue waves,” he said.

The theory, published in Proceedings of Royal Society A, is a special solution of the non-linear Schrodinger equation that is localised in time and space.

Akhmediev’s theory may also explain freak waves that wash away people from beaches, as the rogue waves can sometimes transform into travelling waves known as solitons that travel through the ocean like mini-tsunamis until they hit the coastline.

The theory also applies to other chaotic phenomena, such as light travelling in optical fibres, atoms trapped in a Bose–Einstein condensate and the ionosphere in the upper atmosphere.

Akhmediev plans to add more terms to his solution to account for the influence of the wind on waves.