Tsunamis and the energy of atomic bombs

Despite the title, this is not about the shaky state of several nuclear power plants in post-tsunami Japan. Rather, I want to fawn over Kenneth Chang’s piece, The Destructive Power of Water (NYT 12 Mar 2011). An excerpt:

A typical bathtub holds 40 gallons or so of water. That is 330 pounds. A cubic yard of it, filling what at first glance seems a modest volume of 3 feet by 3 feet by 3 feet, weighs nearly 1,700 pounds, as much as the Smart micro car.

And when water is moving at 30 or 40 miles an hour, like the tsunami that inundated northern Japan on Friday, the heaviness of water turns deadly. Imagine 1,700 pounds hitting you at that speed, and each cubic yard of water as another 1,700 pounds bearing down on you. The destructiveness of a tsunami is not just one runaway car, but a fleet of them.

Explanatory science writing at its best. I love, love, love coming up with these kinds of dimensional reference points so that people really get what I’m talking about (Chang, by the way, is an alumnus of the same SciCom program at UCSC that I just finished last year). One of the professors cited in the article estimates the energy of the tsunami was comparable to that of an atomic bomb. Except we’re talking about sheer mechanical destruction instead of harmful radiation. Unless you count the shaky nuclear reactors …

Maybe I shouldn’t be talking about atomic bomb equivalents hitting Japan.

The point is that water is heavy, and it packs a punch. And the idea brings to mind a director describing the filming of an iconic scene in the 1983 movie Flashdance. A huge bucket of water is dropped on Jennifer Beals’ chest while her character, a dancer, is auditioning. Skip to about 1:25 in this Irene Cara video to watch that moment:

You can see her bracing quite hard against the chair, and watch her torso recoil in slow motion at the impact. According to the director, the first time they tried it, they used a lot more water and pretty much crushed her. And it hurt. Like trying to drink from a firehose.