Rogue Waves Essay

Rogue Waves

Description

Rogue waves are surface waves over water that are unpredictable and have unnaturally large amplitude. To be classified a rogue wave, a wave must be more than twice the significant wave height, or the average of the largest third of waves in a given period of time. These waves are dangerous, even to large ships, and can even flow ashore, pulling people into the water.

Research on the topic is still ongoing so there are many different proposed mechanisms for the creation of rogue waves. There are likely multiple factors at play, as several proposed mechanisms have been gaining ground with increasing evidence. One commonly observed cause of rogue waves is the meeting of opposing currents. When a wave swell hits a current

Surface waves, even those generated in the same way from the same source, are not of uniform height; some are smaller and some are larger. This randomness implies that rogue waves may just be a demonstration of probability.

While the creation of rogue waves commonly centers around constructive interference of smaller waves, there are situations where the phenomena is caused by nonlinear effects. As a wave group moves through the ocean, unstable conditions can cause energy to exchange between waves. Soon, the energy focuses into one wave which becomes significantly larger than those around it. This mechanism can be described by the nonlinear Schrodinger’s equation. One solution to this equation that accurately describes rogue waves is the Peregrine soliton. A soliton is solitary wave that travels like a particle. It maintains a permanent shape when moving at a constant speed and when it collides with another soliton, it emerges with the same speed and shape. However, a soliton’s extreme stability does not match the observations of some rogue waves which appear spontaneously and fade shortly after. The Peregrine soliton remedies this inconsistency. Unlike the usual soliton, it does not maintain the same shape. Instead the Peregrine soliton’s gets progressively taller and more narrow. After reaching maximum compression, at which amplitude is 3 times the level of the surroundings, the wave begins to flatten out and