Monster Waves

For the longest time, the thought of monster waves coming from out of nowhere was believed to be a part of maritime folklore. Tales of sailors and ships encountering massive walls of water in otherwise calm conditions were met with head nodding, an “uh huh” and either a reassuring pat on the shoulder or a glass of milk. (We can’t confirm that this is what happened, but it’s far less impolite than what their reactions of those that were told probably were.) It’s understandable when there was no concrete proof and the characteristics say a tall wall of water formed and was followed by a hole in the sea. At one time these were just tales, but 16 years ago they were proven to be real.

The “Draupner wave” as it is known is the first ever recorded rogue wave by a measuring instrument. A rogue wave is not a common occurrence, but it’s also not a freak occurrence. Rogue waves are not the largest ever recorded waves, those are tsunamis, but a tsunami is rarely felt out in the ocean and usually only damage ships that are moored within the shores of the area that the tsunami is affecting. A rogue wave will happen out at sea and can severely damage or even sink large ships. Storm waves in the ocean can usually reach heights of 20-50 feet. A rogue wave can reach heights of 95 feet, and there is a report of a wave reaching 130 feet high, but this cannot be confirmed as a rogue wave-- although all signs seem to point to that conclusion.

The characteristics of the rogue wave are interesting since the water pushes up creating a deep trough in behind the wave. Rogue waves are not uncommon in the Great Lakes, either. There is a rogue wave phenomenon in the Great Lakes known as the “Three Sisters,” wherein one wave will hit the ship and before the wave breaks, the second wave will come in, followed by the third wave. This causes an immense weight on the ship as there is tons of water on the deck. These types of waves are now believed to have been the cause of the sinking of the SS Edmund Fitzgerald on Lake Superior in 1975.

One night a storm had set in over the Great Lakes in November. These types of storms are known as the “Witch of November” or the “November Witch” where the gales can be hurricane force. These storms occur when the warm air from the south meets the cold air from Canada. The Edmund Fitzgerald’s sinking was believed that during the storm the hulls took on water or there was poor navigation which caused the ship to run aground on shoals. During the storm the Fitzgerald was badly slowed and listing, and ten minutes before she sank, the other ship she was travelling with, SS Arthur M. Anderson, was hit with the three sisters and the waves moved on, heading in a path towards the Fitzgerald. What we do know is that the final transmission between the Fitzgerald and the Anderson was Fitzgerald reporting “we are holding our own.” The ship sank within 10 minutes of that final transmission.

Another famous ship reported to have been hit by a rogue wave was the RMS Queen Mary during the Second World War. In December of 1942, while the RMS Queen Mary was carrying troops from New York to England the ship was caught in a storm near Scotland. A rogue wave with a height of 28 to 30 meters was believed to have struck the Queen Mary on the broadside of the ship. This caused the Queen Mary to list 52 degrees, at 55 degrees it would have capsized. The RMS Queen Mary slowly righted itself and was able to make it to harbour.

Rogue waves are most common in the Agulhas current off the east coast of South Africa, with numerous well documented cases of extreme individual waves, including some striking photographs of damaged ships.

Here is shown bow damage received by Norwegian tanker Wilstar in 1974: the combination of pitch motion and a steep incoming wave can cause excessive local structural damage. One of the aims of rogue wave research is to recommend changes in ship design to make them less vulnerable in future.

Credits: Image courtesy of H.Gunther and W.Rosenthal