From Blamblog comes word that scientists fear the destruction of the U.S. East Coast from a giant tsunami within the next 1000 years. Don’t think Deep Impact, think something closer to home, like the violent eruption of the Cumbre Vieja volcano in the Canary Islands.
…scientists believe the threat from the volcano of Cumbre Vieja on the island of La Palma is real, and that it could send a massive slab of rock twice the size of the Isle of Man crashing into the Atlantic.
(This is not a new story. Here’s an article on the very same subject, dated Wednesday, September 5, 2001. Intriguingly, its wave heights do not correspond to those stated in the Independent’s article. It remains at the centre of a previous outbreak of this story among the blogosphere, before 9/11 cut the discussion short)
Not surprisingly, the scientists quoted in this article believe that more money should be spent on seismology equipment in order to monitor the threat:
A monitoring station equipped to look deep into the heart of the mountain and spot the early signs of an eruption might cost hundreds of thousands of pounds. In comparison, the US was spending $4m a year scouring the skies for kilometre-sized asteroids which were much less of a threat, Professor McGuire said.
A couple of interesting things about this article. One, it’s posted on News dot Independent dot co dot uk. Despite this, the majority of the article focuses on the possibility of Boston, New York, Washington DC and Miami being totally wiped out (presumably Halifax and St. John’s too). Author Steve Connor (the Independent’s science editor) spends one paragraph detailing the threat to West Africa, and two paragraphs detailing the threat to the United Kingdom and Europe.
Is the Independent read by more Americans than Brits or something?
Also, while the threat is real, let’s put some perspective on it:
The wave front from the collapse of the mountain would spread out in a crescent, striking the west African coast with a wall of water more than 300ft high in two to three hours. Its northern side would also brush against Europe. Within three to four hours, a 33ft-high wave would smash into the south coast of England, causing immense damage.
A tsunami launched by a (I assume) Krakatoa-sized eruption would be 300 feet high if it struck land two to three hours later. Three to four hours after that, the wave would be 33 feet high. This is, of course, because the wave is spreading out like a widening ripple in a pond after you drop in a stone, distributing the force of the initial explosion over a wider area. The article itself notes that the tsunami would take nine hours to reach the Eastern Seaboard, two hours after a 33ft wave strikes the south of England.
In short, expect damage, but probably hurricane level, as opposed to Deep Impact level. There are rogue waves in the middle of the Atlantic right now which are over 30 metres (over 90 feet) high. A 33 foot tall tsunami won’t wipe out the Eastern Seaboard, although the damage would still be in the billions.
Still, a 300 foot tall wave hitting the west coast of Africa is no joke. So it might be prudent if we did invest in the seismology equipment for the Canary Islands after all. Ideally, the station should be staffed by Jeff Goldblum playing the lonely, long-haired scientist with all the data whom no one ever listens to. You now the role.
I did say it was no joke. I apologize.
Krakatoa and Tsunamis, Notes and Considerations
The tsunami generated by Krakatoa that devastated Java and Sumatra (295 towns and villages gone, 36417 people drowned; one warship carried three kilometres inland) was actually multiple waves generated by the multiple explosions of the eruption. The waves never topped 37 metres (120 feet). Why West Africa would be hit by a 300 foot wall of water is likely because of the land mass involved. The island of La Palma is larger and far less stable, and thus a larger chunk of land could fall into the sea as a result of the explosion, throwing up more water.
That said, the waves that rushed away from Krakatoa crossed the world. They were noted in Hawaii, the American west coast, and Alaska’s Kodiak Island. Outside of Indonesia, the highest change in water level reported was on the coast of India, at 1.5 metres.
Similarly, it’s been noted that while Alaskan earthquakes have probably been responsible for tsunamis that destroyed Hawaiian villages in the past, evidence suggests that the 366 metre waves that hit Hawaii way back in the past were likely the result of “gigantic submarine landslides that removed large parts of the Hawaiian volcanoes”. There is no evidence I am aware of 366 metre waves hitting Alaska or Vancouver Island around the same time.
The fact that Krakatoa exploded in the midst of a bunch of islands probably helped a lot to diffuse the force of the waves, however. Tsunamis are also susceptible to elements which might focus their intensity, such as the shape of a coastline, where all that water might be channelled into a narrow estuary with a major city at the other end. Another thing to consider is that England’s lower wave height might be the result of its wave having to refract around the Ibernian peninsula.
More on the 2001 Article
The Independent article does not quote wave heights for the United States. This article from Disaster Relief does:
Over the next five to 45 minutes, a series of waves would ripple outward, their crests reaching 150 feet before barreling into the African coast, Spain and England. — Six hours after the eruption, waves reaching 30 feet would arrive in Newfoundland and 45- to 60-foot waves would bombard South America, swamping large parts of land. Nine hours after the eruption, crests reaching 30 to 70 feet would collide into the East Coast of the United States.
Both articles agree on the time it takes the waves to reach the United States. They disagree on the time it takes to reach England, and the size of the waves involved.
Disaster Relief also tells us, to put it bluntly, get a grip:
However, scientists say the entire area of unstable slope may not fall at once. Instead, smaller landslides may occur over time. These landslides would produce waves one-fourth to half the height of the mega tsunami. Moreover, the disaster is not expected to happen anytime soon. The Cumbre Vieja Volcano last erupted in 1949 and has shown no signs of activity.
“Let’s not scare people,” Ward told the Associated Press. “Certainly there is no indication that this will happen anytime soon.” Even if an eruption occurs, a landslide is not inevitable, he added.
Fear versus Prudence
These articles, and the attention they’re receiving right now in the blogosphere, illustrate that there is considerable incentive out there for people to convince other people to live in an everpresent state of fear. From security systems to firearms to insurance, fear catches attention, and sells a lot of product. Fear even commands a lot of votes. You want to live happier? Resolve to live without fear. Accept the fact that you are going to die sometime, and don’t waste your time trying to second-guess yourself as to when that will happen, and how you can stop it.
This shouldn’t stop you from being prudent, however. Eat a balanced diet. Invest in insurance. If you can take steps to protect yourself that doesn’t cause you to live your life differently or less well, then you are not hurting yourself with fear. In many cases, the prudent steps you take to avoid death also serve to enhance your quality of life.
An example of the difference between fear versus prudence, in my opinion, was shown on CP24: a thin plastic film that, when applied over windows, renders the windows shatterproof and bulletproof. The company making this stuff (US ACE Security Laminates) is heavily into using the war on terror as their primary marketing tactic. They’ve shot the glass with machine guns and it would crack but not shatter; they’ve blown up car bombs beside it, and it would not shatter.
And I’m saying to myself, this piece of passive protection might be worth investing in and applying to as many windows as possible across the continent. Not only could this be a more effective saver of lives in the event of a terrorist attack than, say, colour-coded, fear-inducing security alerts, but I have to wonder how well this film copes with the destruction in the event of a tornado or a hurricane.
A simple product that protects lives from a variety of situations while not significantly hampering one’s quality of life. That’s prudent.
- Rogue Waves - no longer a myth
- A picture and story of a spectacular wave.
- Notes from the Rogue Wave Conference of 2000.
- A resource on tsunamis.
- Forget La Palma, according to this, cracks in the continental shelf could have the same effect on the East Coast, with less warning!
- And finally, as somebody else will be linking to this eventually, tsunamis and their role in the apocalypse.