"Now, rogue waves with no known mechanical cause are known to occur on a semi-regular basis. Scientists think that a perfect combination of events may be responsible for generating rogue waves. Waves propagating with different wavelengths can cause wave 'focusing,' in which the shape and size of obstacles and irregularities on the ocean floor cause the energy to compress at the front of the wave towards the shoreline. It is theorized that when these focused waves are superimposed on a chaotic ocean background, giant waves could form. Researchers are attempting to recreate rogue-wave-generating conditions in a laboratory wave tank by modeling ocean current focusing for local effects and non-linear wave oscillations described by a series of Schrodinger equations."