Underwater Nuclear Bomb Tests?

I understand that the USA detonated several atoic bombs underwater, in the 1950’s. My question: what sort of contamination would such a blast produce? And would most of the radioactive stuff just sink to the bottom? Has anyone gone to see what the bottom looked like, after these tests?

I have no idea, but I’d love to chime in to say that I’ve often wondered the exact same thing. I can imagine that you would have some incredibly shocked and confused whales before they were incinerated.

Although not quite as shocked as they would be if they suddenly appeared several miles above the earth and plummeted to their doom, but you get my drift

There were only a handful… maybe three… but the military’s reports from those tests have been declassified and can be read online . The relevant tests were
Operation Crossroads (1946) Operation Castle (1954), and Operation Wigwam (1955) . (WARNING PDFs) Castle was a surface blast, Crossroads was a shallow underwater test, and Wigwan was a deep underwater test. I’m not a physicist, but my layman’s reading of the first two reports suggest they found almost no water contamination. Here’s an excerpt from the report on Wigwam:

The full report for Wigwam is 266 pages, so there’s a lot more detail if you’re interested.

I don’t think there has been any followup testing of what it’s like under the surface other than what’s detailed in the report, and that was several weeks after the test.

I didn’t know where to point you for the underwater tests.

The Bikini Atoll tests have lots of documentation. They certainly dealt with exposing ships, and person to radiation. I found a link I really liked on a naval art page. It has paintings done by artists that were present for the tests. Many have explanations under them, and I think they help get a feel for what it was like to be there. One picture I found to capture the moment uniquely was the drawing titled

How We Looked to the Atom Bomb

On the third page you find a number of pictures about the burning naval vessels.

You may also wish to look into Trinity Test and Manhattan Project.

Details on Operation Wigwam:

Video of complete government motion picture about Operation Wigwam (and Operation Argus).

If you want to see some amazing color footage from Operation Crossroads, and from other nuclear tests of the WWII and post-war era, i highly recommend Trinity and Beyond: The Atomic Bomb Movie. It’s an excellent documentary, with narration by the inimitable William Shatner.