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Monday, December 18, 2006

The truth about rogue waves -- Do we know?

Peter Calamai's Toronto Star article published yesterday with a rather touchy title of "The truth about rogue waves." It is a well written article, not only because I was his main source on rogue waves and he quoted me prominently. But I was also impressed with his well done research on the topic that includes all the appropriate historical perspectives. He obviously also interviewed some of the crew members on the tall ship Picton Castle. As a result he brought forth the question of whether or not the ship was really encountered a rogue wave:
Witnesses have said that the Picton Castle was heaving through 70- to 80-knot winds with waves ranging up to seven metres, a common height for mid-ocean storm waves.

In those circumstances the significant wave height would likely have been a minimum of five metres, meaning that a true rogue wave would have had to have been at least 11 metres high.

That's enough to tower as much as five or six metres above the aft deck and to comfortably reach to the barque's higher quarterdeck level, location of the wheel and charthouse.

The two crew in those spots say they heard Laura Gainey's cry. Yet they did not report seeing any crashing wall of water, so news accounts of a "rogue" wave are probably exaggerated.

Nonetheless science is showing that the cruel sea is much crueller than even we imagined.
I think this doubt is well taken. Too often whenever rogue waves are mentioned people tend to just willingly accept it as a fact. Calamai shows what a superb reporter should do: asking the right questions and present the fact that may rightfully challenge the overriding popular premise.

By the way, Calamai is the only one, among all the people who had interviewed me, who could explain to me offhand what a "significant wave height " is!

1 comment:

D said...

Just to clarify -- the statement: "Witnesses have said that the Picton Castle was heaving through 70- to 80-knot winds..." has a misprint. The unit of measure should be kilometers per hour. Also, there's been a lot of speculation as to the wind speed. The only credible statement I've read about wind speed was from Petty Officer Donna Jefferson of the U.S. Coast Guard who said: "winds were gusting at 55 and 75 kilometers an hour..."; which is about 30- to 40-knots. My thoughts go out to everyone involved in this sad loss of life.