# Atomic Bombs and Tsunamis **URL:** \ **Category:** Factual Questions\ **Created:** [March 13, 2011, 8:30pm UTC](https://boards.straightdope.com/t/atomic-bombs-and-tsunamis/574581 "2011-03-13T20:30:07Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![jbaker](https://avatars.discourse-cdn.com/v4/letter/j/59ef9b/32.png) [@jbaker](https://boards.straightdope.com/u/jbaker)\ **Post date:** [March 13, 2011, 8:30pm UTC](https://boards.straightdope.com/t/atomic-bombs-and-tsunamis/574581/1 "2011-03-13T20:30:07Z")
According to Professor Yeh at Oregon State University, as reported in the New York Times, [http://www.nytimes.com/2011/03/13/weekinreview/13water.html](http://www.nytimes.com/2011/03/13/weekinreview/13water.html), the energy going into the Sendai tsunami was a bit less than that of an exploding atomic bomb. That surprised me; I would have thought it to be much more. Usually we think of atomic bombs as being aimed at population centers or strategic targets. But could an atomic bomb actually cause a tsunami? If so, it would seem that it might be able to cause more damage that way than in a direct attack. ---
**Author:** ![Jeff\_Lichtman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jeff_lichtman/32/1531_2.png) [@Jeff\_Lichtman](https://boards.straightdope.com/u/Jeff_Lichtman)\ **Post date:** [March 14, 2011, 8:20am UTC](https://boards.straightdope.com/t/atomic-bombs-and-tsunamis/574581/2 "2011-03-14T08:20:45Z")
The energy in the tsunami is considerably less than the total energy released by the earthquake. According to the Wikipedia article on the Richter scale, a 9.0 earthquake releases the energy equivalent of 474 megatons of TNT. The biggest nuclear weapons today have a yield of about 500 kilotons, or about 0.1% of the energy yield of the entire quake. There used to be nuclear weapons in the 25 megaton range (or about 5% of the quake’s energy). There were underwater nuclear tests before they were banned by treaty. I don’t know of any case where a test caused a tsunami. I don’t see any reason why an underwater explosion couldn’t. I don’t think that using a nuclear weapon to create a tsunami would be an effective tactic for a few reasons: - The creation of a tsunami by an underwater disturbance is not a sure thing. Most underwater earthquakes don’t cause tsunamis. - Deployment would be difficult. You’d have to get a bomb down to the bottom of the ocean near the enemy’s coast. - It would be useful only against coastal targets. - It would waste a lot of the bomb’s energy. Consider the current tsunami - while it’s true that it caused a lot of destruction, how much more destruction would there be from a nuclear weapon of equivalent energy detonated over land? The A-bomb that destroyed Hiroshima was relatively small, and it caused a lot more damage than the tsunami did. ---
**Author:** ![Alka\_Seltzer](https://avatars.discourse-cdn.com/v4/letter/a/c89c15/32.png) [@Alka\_Seltzer](https://boards.straightdope.com/u/Alka_Seltzer)\ **Post date:** [March 14, 2011, 11:32am UTC](https://boards.straightdope.com/t/atomic-bombs-and-tsunamis/574581/3 "2011-03-14T11:32:05Z")
I’m not sure you could form a tsunami with a (single) nuclear explosion. While it would certainly displace a lot of water, the resulting wave might have very different characteristics. An earthquake releases its energy across a wide area over a period of several second, while a nuclear explosion is localised and almost instant. A tsunami wave has a very small amplitude (wave height of only a few inches) in open water and a very long wavelength (tens to hundreds of kilometres). I’d imagine an underwater nuclear explosion would produce a wave with a very large amplitude and a relatively short wavelength.