Las Palmas volcano

Better break out the life rafts

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Moriarty
mrmoriarty@eircom.net

<font face="Verdana, Arial" size="2">Originally posted by Hecate:
was anybody listening to joe duffy during the week where he had someone on talking about this volcano in the canary islands that may erupt soon, causing a landslide the size of the isle of man.</font>

Not quite true....

The canary islands have a fault line running down their centre, and the west side of the island is quite fragile.

It is believed that at some point a large amount of the west-side will collapse en masee, having the effects which you described or more.

However, there is no evidence to say that a volcanic eruption will actually provide enough force for this to happen, nor that the collapse *will* happen en masse, which is a requirement for the mega-tsunami to form.

Last time I saw an article on this, it said that the Cumbre Vieja erupts on average every 200 years, and that there was one 50 years ago. Also, there is little evidence to say that only one more eruption is needed - it could be a lot longer.

Horizons on BBC did an episode on mega-tsunamis at the end of last year. One relatively recent example was in a sound in Alaska (?) where a collapse on one side caused a 150m wave to devastate upslope on the far side. Scientific modelling showed that this was indeed caused by a smaller version of the process needed for a mega-tsunami.

To be honest, Joe Duffy has some interesting stuff, but I would hardly consider it to be scientific reporting. More likely, some guys has done a new study on it and declared it will happen in our lifetime, and is milking the airwaves on it. I could, of course, be wrong on that.

As for not causing any seagoing damage...thats highly debateable. While the wave will be quite shallow in draft (due to the mecanics of its creation) it will push/pull a massive airfront along with it, which it will perpetuate by dint of the wave's own velocity and mass. This could cause huge damage.

I'm not sure how it could touch the south coast of ireland though, given that it will start at the canaries, and move westward from there.

For interesting reading, go have a look at http://www.bbc.co.uk/science/horizon/mega_tsunami_transcript.shtml

Theres also an interesting Q&A link off it.

jc

<font face="Verdana, Arial" size="2">Originally posted by Victor:
Surely a wave caused by a 'single' incident should travel in all directions? Much like a rain drop in a puddle.
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Yes and no.

Bearing in mind that the wave will be created by a landmass falling into the water in a specific direction, it is inevitable that the greatest force of the wave will be "straight out" from the island, as opposed to a radial effect like a raindrop.

The effect would be more akin to the wash created from launching a large boat down a slipway than a raindrop.

Looking at La Palma, it runs almost exactly north-south.

While there will be other smaller waves in other directions, you will still only realistically have an arc of about 180 degrees which can generate waves of any significant amount of force, which will be essentially running from due north to due south. Ireland is somewhat north and East of the island, and therefore would be shielded by the island of La Palma itself.

Looking at a map of Europe which goes down a far as the Canaries, you will also notice that were a wave to travel in the direction of Ireland, it would actually be capable of hitting the entire west coast, and most of the southern coast....with the west coast being far more likley than the south (although Kerry would probably be the most probable point of impact).

So, while Ireland *could* be effected, it would almost definitely not be by the "mega tsunami" which would hit the US, and its not even definite that we'd get hit at all.

jc