Expert Warns Of Giant Tidal Wave

Kieckerjan writes "Forget about asteroids and start worrying about the unassuming Cumbre Vieja volcano. According to prof. Bill McGuire of the Benfield Grieg Hazard Research Centre, if this mountain erupts, it could cause a tidal wave that would wipe out America's east coast. Google news has the same story over and over again. (This makes you wonder: how much would it take to trigger an eruption for one bent on destruction?)"

Comments

Re:Cliff

[TheLink]

Yeah, but once the waves pass each other they'll keep going on and now you have two huge waves causing trouble elsewhere at the not-so-precise locations...

The energy in each wave isn't going to vanish so conveniently.

Re:Rock & Wave

[Scarblac]

This rock is HUGE.

The BBC article linked to gives the size as that of "a small island", this other BBC news article gives it as "the size of the Isle of Man". According to the CIA World Factbook, that is 572 sq m., or "three times the size of Washington, DC. It also metnions that the rock is already in motion.

Actually, this PDF (Google HTML version) gives it as between 150 and 500 cubic km of rock. That is obviously far too large to get rid of. If it slides into the sea at 100 m/s (as in a volcanical eruption), it could cause waves of up to 25m high in the Americas (well, it's 10 to 25 for the biggest rock size).

(Excuse me if some of the above links are actually in the story, I had read a bit about it already so didn't look closely at the given links)

Re:Rock & Wave

[scupper]

These Diagrams of La Palma mega tsunami wave dissemination are scary

Link to the original paper

[cr00ked]

http://www.es.ucsc.edu/~ward/papers/La_Palma_grl.p df

Re:Don't forget

[LizardKing]

These are the models you seek.

Whole or in pieces, same effect

[Engineer-Poet]

Aside from the wonderful time you'd have wiring up a few hundred cubic km of rock with explosives, there's the question of the good it would do. In this case, it would probably be zero.

The problem here is that the rock goes down and displaces water, which comes up. The potential energy of the falling rock is partially converted into kinetic energy of the water, which becomes a tsunami when it hits the surface. You are not going to get rid of this energy by fragmenting the rock. Some tsunamis appear to have been caused by mudslides, and it's hard to get any more fragmented than mud.

Re:Yellowstone Supervolcano

[TheGatekeeper]

Is it true that the next eruption of Yellowstone is overdue?

No. The fact that two eruptive intervals (2.1 million to 1.3 million and 1.3 million to 640,000 years ago) are of similar length does not mean that the next eruption will necessarily occur after another similar interval. The physical mechanisms may have changed with time. Furthermore, any inferences based on these two intervals would take into account too few data to be statistically meaningful. To say that an eruption that might happen in ten's or hundred's of thousand's of years is "overdue" would be a gross overstatement. On the other hand we cannot discount the possibility of such an event occurring some time in the future, given Yellowstone's volcanic history and the continued presence of magma beneath the Yellowstone caldera.

From the US Geological Survey's Yellowstone Page.

Re:Yellowstone Supervolcano

[squiggleslash]

It's about 20,000 years overdue to erupt.

The US Geological Survey doesn't agree with this:

The fact that two eruptive intervals (2.1 million to 1.3 million and 1.3 million to 640,000 years ago) are of similar length does not mean that the next eruption will necessarily occur after another similar interval. The physical mechanisms may have changed with time. Furthermore, any inferences based on these two intervals would take into account too few data to be statistically meaningful. To say that an eruption that might happen in ten's or hundred's of thousand's of years is "overdue" would be a gross overstatement. On the other hand we cannot discount the possibility of such an event occurring some time in the future, given Yellowstone's volcanic history and the continued presence of magma beneath the Yellowstone caldera.

So it might go off, but to say it's any number of years "overdue" is pushing it. If it last went off 640,000 years ago, you could argue it's "639,999 years overdue", or you could just say it's not overdue at all because it's not exactly running on a timer.

Re:Surf's Up?

[putzin]

The reason this would be big is because the wave, as it approaches the coast, would expand upward as the depth decreases. The energy dissipation follows wave form rules, but as in any system, the energy involved doesn't go away. So, as the water gets shallow, the wave would grow up. Interesting to note that there would be no 300 foot wave in deep water, but the wave form itself would still exist and be travelling at a high rate of speed despite being essentially invisible.

As a side note, Dr. No, GoldFinger, and Dr. Evil all investigated this and decided it wasn't grand enough for a take over the world plot. Not reproducible, like a laser or nuclear weapon, and possibly defensible (blow up the rock before it slides?).