Wednesday, December 29, 2004

A wake-up call

As horrific as it was, the Sumatra tsunami was just a ripple compared with the megatsunami waiting to scour the U.S. East Coast.

I've posted on this subject before, but there has never been a better time than now to raise awareness of the ticking time bomb at La Palma in the Canary Islands.

Earthquake-generated tsunamis are nothing compared with those triggered by massive landslides and volcanic islands are the primary cause of these rare but inevitable cataclysmic events.

The trigger will be the collapse of the western flank of the Cumbre Vieja volcano on La Palma. There is already a massive fracture that slipped a short distance during an eruption in the latter portion of the 20th century. The speculation is that the next time the volcano cranks up, a major eruption will cause all or part of the western flank of the volcano to plunge into the Atlantic Ocean.

Scientists predict the collapse will generate a train of a dozen or more very large waves spreading out in an arc that will strike the eastern coasts of North and South American, as well as the Caribbean.

As we saw with the Sumatra event, the wave height increases as it moves into shallower water. It was estimated as high as 20 feet and reached as far as a quarter-mile inland in the Indian Ocean tsunami.

A La Palma megatsunami would generate waves as tall as 160 feet (8x the Sumatra size) that would reach as far as 12 miles inland all the way from Greenland, down the densely populated U.S. East Coast to Brazil and beyond.

It is estimated that the northeast coast of Brazil would feel the impact first, some six hours after the collapse, with Haiti, Cuba and the U.S. East Coast following in rapid succession.

Take a look at a map of the U.S. East Coast and notice how much population is concentrated within 12 miles of the shore from Maine down to Miami and you begin to appreciate the almost inconceivable destruction.

Think of the massive traffic jams caused by Florida residents fleeing hurrincanes and then imagine the futility of trying to evacuate that danger zone with little more than six hours' warning.

Scientists say there is no way to predict when the La Palma collapse will occur - only that it will occur. Maybe in 1,000 years, maybe tomorrow.
Here's a place to start to learn more:
http://www.bbc.co.uk/science/horizon/2000/mega_tsunami.shtml

No comments: