Atomic Bomb Simulator link.

Nukmap and Nukmap3d
A nuclear weapons effects simulator for Google Earth.

"Restricted Data" is a blog about nuclear secrecy, past and present, run by Alex Wellerstein, a historian of science at the Stevens Institute of Technology. Alex provides a lot of information on his blog site.

Links;
http://nuclearsecrecy.com (Restricted Data blog)
http://nuclearsecrecy.com/nukemap/
http://nuclearsecrecy.com/nukemap3d/
http://nuclearsecrecy.com/nukemap/faq/

With this simulator you can select different size weapons and detention altitudes. Then see the effects on Google Maps along with the simulated fallout area.

This site can also be used to map the effects of a nuclear reactor accident.
Do you know that the Chernobyl explosion put 400 times more radioactive material into the Earth's atmosphere than the atomic bomb dropped on Hiroshima. Atomic weapons tests conducted in the 1950s and 1960s all together are estimated to have put some 100 to 1,000 times more radioactive material into the atmosphere than the Chernobyl accident.

Chernobyl was believed to have released 30 to 40 times as much lethal ash as the atomic bombs dropped over the Japanese cities of Hiroshima and Nagasaki in 1945, according to Japanese news media reports. These were 15 to 20 Kt.