The biggest tsunami wave ever measured occurred in Lituya Bay(southern coast of Alaska) in 1958. After an earthquake measuring 8.3 on the Richter scale hit the area an estimated 40 million cubic yards of dirt and glacier broke loose from a mountainside at the head of the bay. The debris hitting the water caused a massive 524.3 m wave to wash over the headland.
To measure the height of the wave, scientists found the line where the water reached its highest point on land(high water mark). It wasn’t difficult to find since there was no soil or vegetation left where the water hit land. This probably is not the biggest wave ever, just the biggest documented. Three fishing boats witnessed the event. Incredibly, two of the boats rode the waves and their occupants survived.
Rogue waves(a.k.a freak waves) are giant walls of water that dwarf run-of-the-mill storm swells. For ages, mariners have told of much bigger mid-ocean waves that they claim have risen more than 200 feet to hammer ships. In recent years these waves have been the subject of studies because of the availability of ocean-monitoring satellites. The European Space Agency has used its MaxWave satellite radar project to detect more than 10 rogue waves measuring higher than 25 meters over a brief period including 30.5 m whoppers.
Many people believe that the biggest wave ever ridden was 13.7 m by Ken Bradshaw in 1998. There is a video of Miguel Del Toro riding a wave touted as being 30.5 m, but that video was faked as a promotional event.
Waves have destroyed ships and entire cities according to ancient, and not so ancient, reports. Until recently there was no technology capable of recording them. Is it possible the there have been waves that would have dwarfed the 524.3 m goliath that hit Alaska?
Source : Universe today