Largest Tsunami

[Dayman]

I can't believe that the largest tsunami in the world was 525 m high...

2 m shorter than the Sears Tower in Chicago.

http://wcatwc.arh.noaa.gov/web_tsus/...0/19580710.htm





HOW CAN A WAVE GET THAT BIG? I'm scared now

[boofhead]

Boeing that is extremely frightening - I found the following report there:

"...Still farther south, mountain-girt Lituya Bay lay near the foot of 15,320-foot Mount Fairweather itself. Inside LaChausee Spit at the bay entrance were two boats, the Badger, aboard which Bill and Vivian Swanson, of Auburn, Wash., lay asleep, and the Sunmore, occupied by Orville Wagner, of Idaho Inlet, and his young wife Mickey. Farther in, near Lituya's south shore, were Howard Uhlrich and his 7-year-old son Junior, in the 38-foot Edrie. Just in from a day of fishing, they all sought a night's shelter before undertaking another day of labor in the Alaskan Gulf.

...The Swansons and the Uhlrichs in Lituya Bay rose in alarm to gaze in unbelieving wonder and terror. Swanson and his wife later insisted that the terminal ice mass of Lituya Glacier rose into view from behind a headland up the bay, with great masses falling from its face, and then fell majestically into the water, creating a wave that went over the whole headland. It then caromed down the bay, scouring the shores of their trees, obliterating the mountaineer's campsite, overrunning Cenotaph Island and its lone cabin, and killing the Wagners and all but killing the Swansons in a surfboard kind of plunge of their two boats across 40-foot high LaChausee Spit to destruction in the sea outside - a wave of such improbability as to strain the credulity of later investigators, and to remain a scientific puzzle.

...Eyewitness stories of the Lituya Bay events come from the Swansons and from Howard Uhlrich. Bill and Vivian Swanson, occupants of the Badger during her mad flight across LaChausee Spit in company with the ill-fated Wagners, somehow managed to get clear of the wreck in an 8-foot punt, undergoing exposure and fright as well as loss of their worldly possessions, before their rescue by a fisherman named Graham in the trawler Luman. They were quickly flown to Juneau in a rescue plane and, after a short hospital rest, were able to describe their experience. They were sure they had seen the glacier riding high into sight from behind the western mountain, followed by a great wave of water washing over its steep face. During the following wild ride across the spit they believed they were 100 feet high, for there had been trees on the spit, and they were above them. They looked down on rocks as big as houses. They were incredulous and deeply thankful to be alive.

The story told by the other survivors, Howard Uhlrich and his son, will probably be unmatched for a long time to come. In a vivid account published in the Alaska Sportsman Uhlrich tells how they enetered the bay on the last of the floodtide for rest after a day of poor fishing. He anchored Edrie in a cove on the south side a mile or so inside the entrance, and after supper he and Sonny went to sleep, only to be awakened by violent motions soon after 10:15. Dashing to the deck, Uhlrich beheld the writhing and twisting of the high peaks and the clouds of dust and flying snow about their summits. Petrified, he watched for 2 minutes or more until his attention was attracted to a new sight. There was a gigantic wall of water which he thought to be 1800 feet high erupting against the western mountain, then coming down the bay, cutting a swath through the trees on the summit of Cenotaph Island, backlashing against the eastern shore up to a height of 500 feet, then heading for the Edrie, now a wall of water 50 feet high.

Suddenly he realized he had to move. Cursing himself for delaying, he got a life jacket on Sonny, then somehow got the engine going, but he was unable to heave the anchor in time. Just before the water struck he veered the chain to its end, hoping to slip it, at the same time maneuvering the Edrie to face the wave. As she lifted to the swell the chain tightened and snapped, its short end whipping up and winding around the pilothouse. The boat was swept, completely out of control over what had been dry land a moment before. By now Uhlrich remembered his radio. Shouting into it, he made the international voice-radio distress call, "Mayday, Mayday - Edrie in Lituya Bay - all hell broke loose - I think we've had it - goodby!" The wave, however, changed course and bounced off the shore, allowing Uhlrich, with strenuous efforts and certainly with superb seamanship, to get his boat under a kind of control. He now began devoting himself to evading huge chunks of churning ice, any one of which could have made kindling wood of the Edrie."

Luckily it occurred in the middle of nowhere - only 3 boats destroyed and 2 dead. Imagine if it hit New York

[chilon]

If I remember correctly the reason this tsunami grew so huge was that it occured in that Alaskan bay where the water sloshed back and forth multiple times before creating the largest wave. Like a giant equivalent to taking a bowl with water in it and and rocking back and forth till it splashes out one side...

Would have been an intense phenomenon to witness thats for sure...

[Markas]

Well the one we know of was that big. I should imagine the various meteor impacts in our geological history would have created some many miles high. I think the one that occured 225 million years ago(?) was theorised to have been that big.

Still, Tsunamis scare the bejesus out of me.

[nightwar]

Surfs up???

[LSJ]

Tsunamis are pretty scary. Waves going 900 kilometres per hour are not very fun. When they hit the shore they are a lot slower than 900km, but when they do hit the water piles up. And I doubt you'd care if the water is 900 or 100km per hour if the wave is 200 metres high.

[Osceola]

The one created by the Thera eruption in 15th century B.C. that annihilated the Minoans, was supposed to be 5-600 feet high..

[Spurius]

It wasn't a real ocean tsunami, those get up to dozens of meters, not hundreds (although they could, like after an asteroid strike).

It was a huge side of rock sliding into the water, and the height was the highest watermark level, not the actually measured wave. And indeed, in the small bay the water had nowhere to go.

Still mighty impressive if you happen to surf there...

http://www.extremescience.com/BiggestWave.htm

[PacSubCom]

The greatest pity ever to befall the human race is that footage and photographs of Tsunamis are so distressingly rare. The only ones I know of are the ones from the big one 2005, and while impressive, the pictures are only from areas where the wave was quite small.

In other areas, it simply killed all camera men. Shame.