Search This Blog

Saturday, December 28, 2013

The Wave of the Future

Have you ever heard of El Hierro island?  For most people, the answer is no.  Well, El Hierro is one of the smaller islands that form the Canaries.  They are located off the northwest coast of Africa near Morocco.  Right now, El Hierro is in the news because a volcano there looks like it is about to erupt.  There have been swarms of earthquakes and the ground near the volcano has swelled.  The surface is now almost four inches higher than it was last week, a clear indication that pressure from below is moving the surface rock upwards.  The real question, however, is what will happen when the volcano erupts.

The eruption certainly will be bad news for the residents of the island.  If the eruption is large enough, it may also bring problems for the residents of the other Canary Islands.  But that is not the point.  The volcano in question is right on the shore of El Hierro.  When (not if) it erupts, it could send an enormous volume of rock sliding down the side of the volcano and into the Atlantic Ocean.  This is the formula for generating a massive tidal wave.

The volcano on El Hierro is on the southeast shore of the island.  That means that the main force of a tsunami generated by the collapse of part of the volcano into the sea would likely be directed most strongly at the African coast.  Fortunately, the targeted area is lightly populated.  There could be other tsunami waves that hit the Atlantic coastline of other nations, but the impending eruption is not likely to cause massive damage in the USA barring some unexpected twist.

The current eruption, however, should stand as a warning of another likely eruption on Las Palmas.  This is another of the Canary Islands.  There, the volcano erupts on a frequent basis (frequent on a geological basis means every ten to fifty years.)  Las Palmas, however, has a large ridge of land that towers over the shore, and that ridge has been shown to be separating from the rest of the island.  The next eruption or the one after that will most likely send the ridge plunging down into the Atlantic.  This will be a much larger landslide than any expected on El Hierro, and it will generate a massive tsunami that will hit nearly all countries bordering the North Atlantic.  Estimates are that waves as high as three hundred feet could hit the eastern shore of the USA.  The devastation would be enormous and the loss of life unimaginable. 

This is not one of those events that generate stories on the Discovery Channel about the end of the Earth.  It is not something that might happen in twenty thousand years.  It is something that is most likely to happen some time in the next century.  It seems to me that since we know this is coming, we ought to take steps to prevent it.  A massive project to bring down the ridge in a slow and controlled manner might well prevent the future sudden collapse into the sea.  Wouldn't it be better to have a project to move earth that cost a billion or two dollars now rather than the wholesale destruction of much of the Atlantic shoreline in a decade or two?




 

No comments: