New computer simulations may help mariners identify freak wave 'hot spots'

London, August 10 (ANI): A team of oceanographers in the U.S. have achieved a major breakthrough in understanding 'freak waves', the monster waves that present a major risk to ships and offshore platforms.

Tim Janssen of San Francisco State University (SFSU) and Thomas HC Herbers of the Naval Postgraduate School in Monterey, California, say that they have basically created a computer simulation that can help locate where and when these "rogue" phenomena are most likely to occur.

They say that the theoretical study shows that coastal areas with variations in water depth and strong currents are hot spots for freak waves.

According to background information in a research article describing the researchers' work, the history of seafaring is littered with tales of rogue waves capable of rending ships asunder.

A freak wave is one that measures roughly three times higher than other swells on the sea at any one time. These phenomena can measure up to 18m (60ft) - the height of a six-storey building.

Sandbanks and strong currents may cause waves to change direction and speed. This concentrates wave energy into a single point, which oceanographers call a "wave focal zone".

Dr. Janssen describes this zone as a burning glass where the light comes in and focuses all the energy on a single point, forming a hot spot.

The researcher says that the same happens when a wave travels over a sandbank or over a current. The energy is being focused on to a single point.

The computer simulation developed by the researchers suggests that these hot spots were much more likely to drive the formation of extreme waves.

"In a normal wave field, on average, roughly three waves in every 10,000 are extreme waves," the BBC quoted Dr. Janssen as saying.

"In a focal zone, this number could increase to about three in every 1,000 waves," Dr. Janssen added.

During the study, the researchers fed data on real waves into their computer model, and then repeated a single experiment over and over, each time using different data.

The team said that they next hoped to go to known freak wave hotspots, such as the Cortez Banks on the coast of California, to test whether their simulations held true.

"What's really important about this research, is that it is easy to validate. We have a theory now, a prediction, and we can go to areas and actually measure whether this happens or not," Dr. Janssen said.

Understanding where and when freak waves are most likely to occur could assist shipping and navigation in coastal areas.

The knowledge could be used for marine weather forecasts and could also inform the design of offshore platforms. (ANI)