According to a documentary, "Mega Tsunami - A wave of destruction", most mega tsunamis are caused by landslides creating tsunamis 10 times the size as those caused by earthquakes. It was said that there is a volcano in the Canary islands that holds water in an enclosed basin, which heats up every time the volcano erupts. It was said that this basin will cause the surrounding lands to crack and produce a massive landslide that will lead to a tsunami reaching America with a height as tall as a 50 story building.

Is it true that this mega tsunami is inevitable or very likely to occur?

  • 3
    $\begingroup$ Short answer: no. $\endgroup$
    – gerrit
    Apr 17, 2014 at 2:39
  • 2
    $\begingroup$ I say "yes," given enough time (perhaps a million years). But if you ask, "within our lifetimes or those of our children and grandchildren?" Probably not. $\endgroup$
    – Tom Au
    Apr 20, 2014 at 23:47
  • $\begingroup$ But asteroids make the biggest tsunamis of all. If you look at some large craters---Chicxulub, Sudbury, Vredefort---and realize that Earth is only about 30% land...then it seems likely that some similar large objects impacted the ocean and created extreme tsunamis (which would recede in relatively short time, not permanently raise the water level). You might also say that it is just as probable in the future. However, space now is a much calmer place than it was in the past. $\endgroup$
    – DrZ214
    Feb 28, 2017 at 10:31

1 Answer 1


As a lecturer I had during my undergraduate put it: if you draw your information from BBC/Discovery Channel documentaries, you will believe we could get a 100-million-people-killing disaster every week. The collapse of the Cumbre Vieja is but one of those perceived threats.

How do such documentaries get their info? Scientists develop models, then run them. Remember than all models are wrong, but some are useful. Using their models, they speculate that if the substance of the mountain has a certain shape, and if the volcano erupts in a certain way, and if this causes a landslide in a particular way, with a couple of more ifs, then they speculate that there might be a huge tsuname destroying the eastern US. Do they state this with certainty? Absolutely not. Do other scientists agree with them? Not really. Does Discovery channel care that it doesn't appear very likely? No.

The already linked Wikipedia article Cumbre Vieja#Future threats answers this particular one better than I can do. Don't worry and sleep well ;-).

Oh, and you must visit, it is spectacular!

Cumbre Vieja coast
La Palma, 27 December 2012. Certainly, the inhabitants of the shores of the Cumbre Vieja are more at risk than the inhabitants of the US east coast. (P.S. I'm cheating, this is actually some 15 km north of the dangerous part of the slope. But still, if this mega-tsunami does happen, I think the TV networks will forget about the poor islanders :()

  • 1
    $\begingroup$ thanks. The documentary was even so bold as to say in the last line "not if, but when." $\endgroup$
    – Kenshin
    Apr 17, 2014 at 2:51
  • 5
    $\begingroup$ @Mew They always do that, and often it's true. It's not a matter of if a huge meteorite will hit Earth, but when, as it could be 50 million years from now, or it could be tomorrow!. $\endgroup$
    – gerrit
    Apr 17, 2014 at 2:53
  • $\begingroup$ @ gerri: Well, not tomorrow, as NASA &c could provide a few days warning. But maybe next week :-) $\endgroup$
    – jamesqf
    Mar 1, 2017 at 0:00
  • $\begingroup$ @jamesqf That raises the question: why would they bother informing the people? It's not like anything can be done to save any lives. ;-) $\endgroup$
    – gerrit
    Mar 1, 2017 at 0:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.