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For hundreds (maybe even thousands) of years there have been tales of giant waves that come out of nowhere, even on relatively calm days, that capsize ships.  Until recently, science has placed these “rogue waves” in the category of sea monsters and mermaids and have dismissed them.

In 1995 an oil platform in the North Sea produced the first hard evidence of a rogue wave – a laser mounted on a platform that was designed to measure wave height recorded an 84 foot high giant wave (that is really big – about the height of an 8 story building).  Prior to this event in 1995, many scientists doubted the existence of rogue waves.

It is not uncommon for ocean storm waves to reach about 20-25ft in height and while very rare, it is not unheard of for some waves in particularly violent storms to reach 50ft.  But, ocean lore has told of 100ft waves and there are a number of modern accounts of giant rogue waves.  These include:

• 1933 –  a U.S. Navy ship  triangulated from the ship’s superstructure to estimate a rogue wave they encountered to be 112 feet tall.
• 1966 – an Italian cruise ship was damaged when a rogue wave over 80 feet high smashed heavy glass out of its superstructure
• 1978-a German barge carrier sank in the Atlantic ocean and the wreckage suggested that it encountered a huge wave.
• 2005 – the cruise ship “Norwegian Dawn” was hit by a seven-story high wave that “appeared out of nowhere” and caused extensive damage to the ship and flooded 61 cabins.

There are many other reported incidents.  The captains of ships that have survived rogue waves typically describe “a wall of water like a mountain coming towards us.”

Rogue waves are different from Tsunamis.  Tsunamis are typically seismic induced and form low, almost invisible mounds at sea before gaining height before crashing ashore.  Rogue waves are high at sea but cannot survive to shore and only last from 20 seconds to a few minutes.

Over the past 10 years use of radar and satellites have confirmed the existence of rogue waves to the point that science now accepts them as fact.  It is now thought that up to 10 rogue waves exist at any point in time across the world’s oceans.

Ocean waves are mainly the result of wind blowing across open water.  The wind’s force, duration and sweep determine the size of the swells.  IFOD on Waves Currents & Tides. 

Rogue Waves are not created by weather like normal waves. While science is not completely sure what causes rogue waves, recent research using computer modeling suggests that the rogue waves occur due to  various waves and currents acting upon each other in just the right way. According to Francisco Fedele at Georgia Tech: “We found that the main mechanism responsible for generating these waves is the constructive interference of elementary waves due to directional dispersive focusing enhanced by second-order bound nonlinearities.” Rogue Waves occur by chance. The rare combination of waves in what turns out to be a bad place for ships or oil platforms. “It’s just a bad day at the ocean,” said Dr. Fedele.