More killer waves than we thought

THE EUROPEAN SPACE AGENCY has confirmed that freak waves exist in the world’s oceans “in higher numbers than anyone expected.” Wolfgang Rosenthal, senior scientist with the GKSS Research Center in Geesthacht, Germany, says two of the agency’s Earth-scanning satellites used radar to monitor the oceans for three weeks. They identified more than 10 individual giant waves around the globe that were more than 81 feet high.

Laurence Draper, of the British National Institute of Oceanography, has long insisted it’s no old wives’ tale that every fifth, or seventh, or ninth wave is larger than the others. Sea systems are composed of many different wave trains, he says, each with its own speed and height.

So, at random intervals, waves can ride on each other’s backs to form an exceptionally high wave — and it doesn’t have to be blowing hard. Draper estimates that one wave in 23 is twice the average height; one in 1,175 is three times higher; and one in 300,000 is more than four times higher.

But it’s the height of the breaking crest that’s the greatest threat to small sailboats. Luckily, the size of the crest does not necessarily relate to the size of the wave in deep open water.

Watch out for more frequent giant waves when you’re in a strong ocean current. Winds blowing against the current create the biggest and steepest waves.

Today’s Thought

Under every deep a lower deep opens.
— Emerson, Essays, First Series: Circles

Tailpiece

According to the cynics among us, a platonic relationship is the interval between the introduction and the first grope.

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