Wednesday, July 19, 2006

On a 2004 Discover Magazine article

Google is really amazing. Every time you Google you are going to find something new. I Google “rogue waves” from time to time, but today I really found something new: I found a two year old article in Discover Magazine I did not know it existed. I confess that I don’t usually read Discover Magazine. An article by the title of “Rogue Waves: The physics of pure hell at sea” would usually caught my attention real quick, directly or indirectly. Somehow I missed this one and I did not see anybody else mention it either. I guess July of 2004 was also the month that ESA announced the discovery of over 10 monster waves from three weeks of satellite pictures. Most of the world attentions must have occupied by this earth shaking ESA news that overshadowed this Discover article.

Nevertheless it is still a fabulous article. It basically reported an exciting rogue waves laboratory experiment conducted by Professor Al Osborne of the University of Turin of Italy along with his two young colleagues Miguel Onorato and Carlo Brandini at Carl Stansberg’s huge wave tank in Trondheim, Norway. (For the freaque wave aficionada/aficionados these names are by no means strangers.) The three theoreticians from Turin succeeded in theoretically creating likely rogue waves in the wave tank even their local host was doubtful if they can really do it. The writer followed through the whole proceeding and aptly described all the lively excitement of the experiment in the laboratory. Obviously the professor continuously providing detailed explanations with play by plays through out of the experiment. Here is a short segment:

“The first wave starts to live its own life. Then it eats from the other waves”

A wave lifts.

“There. That got to be the leading-edge effect.”

Then two-thirds of the way down the tank, a wave rises higher than the ones before or the ones behind. It has a steep face and a narrow crest.


As he speaks, the wave jumps the pool wall.


Is that what happen in the ocean? We don’t know; but they can certainly enjoy the success of their theory in the laboratory.

But what I like most about this article is that, toward the end, he pointed out an important fact that no one else seem to have ever touched upon. I am not certain if the following quote reflects Osborne’s view point or the writer's own observation. Anyway here is the gem of this article:

. . . there is a serious lack of data. The main means of measuring seas and waves is around 50 years old: Buoys at sea record the heights to which they’re raised. Although many buoys are now supplied with electronic transmitters and high-tech electronics, the likelihood of one being in the path of a rogue wave is small. Even if it is, its anchor will most likely pull it down off the face of the wave before the wave’s true height has been measured. Satellites and aircraft can measure only large-scale effects, and they’re limited by cloud cover.

This “serious lack of data” and the inadequacy of the conventional wave measurements are the crux the whole freaque wave study should seriously confronting today. Because we really don’t know what is really going on out there in the ocean. We don’t know why freaque waves happen, we don’t how freaque waves happen, we don’t know where freaques happen, and we don’t know when freaque waves happen. We only know that they do happen, perhaps more frequent than rare. We need real data, we need real measurements to tell us what's going on. Until a whole new generation of ocean wave measurement is developed and implemented. The research will continue to be listless and sea captains will continue depend on their own luck for safe sailing like they were years and years ago.

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