Massive Waves a Mystery at Maine Harbor

Dockworker Marcy Ingall saw a giant wave in the distance last Tuesday afternoon and stopped in her tracks. It was an hour before low tide in Maine's Boothbay Harbor, yet without warning, the muddy harbor floor suddenly filled with rushing, swirling water.

In 15 minutes, the water rose 12 feet, then receded. And then it happened again. It occurred three times, she said, each time ripping apart docks and splitting wooden pilings.

"It was bizarre," said Ingall, a lifelong resident of the area. "Everybody was like, 'Oh my God, is this the end?' " It was not the apocalypse, but it was a rare phenomenon, one that has baffled researchers. The National Weather Service said ocean levels rapidly rose in Boothbay, Southport, and Bristol in a matter of minutes around 3 p.m. on Oct. 28 to the surprise of ocean watchers. Exactly what caused the rogue waves remains unknown.

"The cause of it is a mystery," said National Weather Service meteorologist John Jensenius, who first reported the waves from a field office in Gray, Maine. "But it's not mysterious that it happened."

Specialists have posed a variety of possible explanations, saying the waves could have been caused by a powerful storm squall or the slumping of mountains of sediment from a steep canyon in the ocean - a sort of mini tsunami. The last time such rogue waves appeared in Maine was at Bass Harbor in 1926.

Jensenius said the occurrence is so unusual, that specialists don't have a name for the phenomenon.

"That's part of our problem," he said.

A similar occurrence in Florida more than 15 years ago continues to baffle researchers. A series of 12- to 15-foot waves hit Daytona Beach on July 3, 1992, injuring more than 20 people and lifting and tossing dozens of cars.

Jeff List, an oceanographer at the US Geological Survey at Woods Hole said he and other researchers studied the occurrence, but no one has been able to pinpoint the cause. And he said similarly enormous waves appeared once on the Great Lakes.

Could such a wave or waves enter Boston Harbor, or even engulf the Massachusetts coast?

"It seems a little unlikely one could hit Boston," List said. "But then again, these things are always surprises when they occur."

A squall line surge, which occurs when fast-moving storm winds sweep over water that is traveling the same speed, can create such a wave. (The speed of waves is directly related to wind speed and the depth of the ocean at any given point.)

List and other specialists said such an occurrence is exceedingly rare, but when it occurs, "you get this interaction that causes a large bulge of water to rise up."

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