mum wave run-up, or height reached on dry land, is not an estimate; it is known exactly. The wave stripped all the trees off the mountains ringing the entrance of the bay to an elevation of 1,700 feet. This is not the largest wave ever recorded, although it is the largest wave that eyewitnesses are known to have survived. There is geologic evidence of even larger waves in prehistoric times—some caused by earthquakes, others presumed to have been caused by the impact of a meteorite in the ocean.

On average, several major vessels are lost every single week somewhere in the world, many from the effects of extreme waves. Not too long ago, a major vessel was lost every day of the year. This statistic does not consider the losses of fishing boats, small boats, and pleasure craft. Peacetime ship losses are reported in six major categories: wrecked; burned; collided; foundered; missing, presumed lost; and “other.”1

“Wrecked” is the most common cause of ship loss; the term means run aground, as the result of either foul weather, equipment failure, or human error—usually navigational error. Fire or explosion is another significant cause of ship loss, due both to the cargo that ships carry and the fuel used for propulsion. Even with radar, traffic separation lanes, and radio communications, collisions still occur—in part perhaps because of the larger, faster vessels in use today—vessels that may require a mile or more to stop or change course. “Other” includes miscellaneous causes; amazingly, even today piracy accounts for ship losses.

The two remaining categories are important for this book. Foundered means sunk at sea—overwhelmed by the influence of wind and wave. Vessels founder because of heavy storms, although human error (mishandling of the ship) or equipment failure (engines fail; hatches or other openings admit water into the vessel) may also contribute to a ship’s sinking. Ships also founder as a result of extreme waves—either a single large wave or several waves in quick succession—that simply overwhelm the vessel, rolling it, damaging it, or in some cases breaking it apart before the crew has time to take evasive action or even make a Mayday call on the radio.2 A wave need not be hundreds of feet high to be considered “extreme.” A wave that is 66 to 98 feet high is large



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