Somewhere around 2 A.M. there was a huge gust—the captain of a neighboring boat thought that it registered 50 knots—and Dreams’ anchor pulled free. We rode backward toward the open sea, dragging the anchor.

Words are inadequate to describe the chaotic scene that ensued: me jumping out of bed in my underwear, probing the darkness with a flashlight—the wind howling, the boat rocking, another crew member running forward to release the windlass and let out more chain, hoping the anchor would catch before we were blown completely out of the cove. Finally the anchor caught and I had a moment to clamber below for pants, shirt, and a jacket. After that, I maintained watch on deck until the sun rose and the wind died.

In the morning I surveyed the scene. The cove was surrounded by a dense growth of kelp. We had entered to one side where there was no kelp and anchored in a clearing broad enough for several boats. The wind had blown us backward several hundred yards through the kelp. Our path was clearly marked; it was as if a giant lawn mower had mowed a swath through the kelp.

A mariner’s worst nightmare is to be blown onto a lee shore. We did not face that risk, since the wind was blowing offshore. Had the wind direction been reversed, I would have certainly set two anchors or, more likely, left the cove entirely for the open ocean. Still, it was enough—another dramatic and lasting lesson of how quickly the weather can change at sea. The wind shifts, waves build, and suddenly conditions are very different.

I spoke earlier of linear models used to analyze the “ideal wave.” While these models lack the sophistication to accurately portray the random nature of real waves, they are useful in explaining certain phenomena we see in the ocean, and they are helpful in understanding how giant waves can suddenly emerge in seas that are average in size. A realistic situation is that one or more storms occur in distant parts of the ocean. Waves are created, and these disperse, the longer wavelengths running at faster speeds and leaving the shorter waves behind. The sudden appearance of these long, low swells that outrace the storm that caused them is sometimes a warning that a storm is approaching.



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