Discussions on the Occurrence Probabilities of Observed Freak Waves

Field observational is the most direct and reliable research approach to investigate the freak waves, particularly for the occurrence probability. In order to present the latest research state, the results related to the observed freak waves from six sea areas are summarized and analyzed with comparisons. Three key conclusions are addressed. Firstly, both the occurrence probability and the strength of freak waves vary much for different sea areas. It is shown that there is still no answer to the big question of whether freak waves are rare events. Secondly, there is no single accepted, unified definition of freak waves. It means the scientists still do not exactly know what a freak wave is. Lastly, it is suggested better to study the combination of potential disaster risk and freak wave occurrence together instead of focusing only on the characteristics of freak waves. Because the results induced by even a same freak wave will change a lot for different structures and victims.