posted on Mar, 3 2005 @ 10:05 AM
Wait a minute; regardless of the yield of the device (in kilotons in this case), there are three other factors that are involved.
(1) Air burst versus ground burst. A detonation at, say, ten thousand feet, will increase the initial damage, since the heat and prompt
gammas, as well as the other radiation, will not be blocked by buildings. In the case of an air burst, probably most people within two miles or
so of ground zero would be roasted or killed in short order by initial radiation effects, and to overpressure (say four or five pounds' worth) would
spread out to a radius of maybe 3-4 miles from ground zero (4 lb overpressure makes large buildings go away).
Also, the radius of the fire would be about 4-5 miles. If there's enough combustible material there, you will have a cyclonic storm which feeds the
firestorm a la the Dresden attacks of 1945, and people in basements outside the firestorm would die because of the oxygen being sucked out to feed the
fire through the cyclonic mini-weather system.
A ground burst, on the other hand, will dig a big crater -- maybe a quarter mile in diameter -- and everything there will become vapor or, at
best, volcanic glass. The blast effects after the cratering will be primarily lateral, which will destroy buildings, but many buildings, as they take
the brunt of the overpressure and heat, will shield buildings and people behind them from the blast. As a result, initial casualties will be
substantially lower, because the blast is contained by its own crater and adjacent objects,
However, the ground burst will loft tons of highly radioactive particles into the air which will come down and probably (depending on the population
of the suburbs and exurbs) kill as many folks as died in the initial blast. How many people die from the subsequent fallout depends on the wind
patterns; whether it rains or not; the half-life of the fallout (typically, for statistical purposes, planners use 14 days); and whether there’re
mountains between the target and the fallout area.
The good news (if you can see anything “good” about a nuclear attack) is that a terrorist nuclear attack would almost assuredly be a ground burst,
since any terrorist can come up with a delivery method for the atomic bomb: a one-ton Ford Econoline van.
(2) Bomb casing material. Depending on how the bomb is made, the same yield device could result in an enhanced-radiation blast (‘neutron
bomb’) which would kill a lot of people but lower the damage level of the blast effects. Or, if there were a cobalt or cesium casing, the resulting
radioisotopes created would make the fallout much more deadly.
(3) Time of day. In a big city like New York, the population and thus the casualties would be much higher during the workday. At night or
during the weekend, a large portion of the folks would’ve retreated to their suburban homes. A bomb going off at rush hour would be even more
effective, as it would trap and kill untold thousands of subway riders.
I’m sorry I can't come up with anything more concrete; the planning for a nuclear attack is a tough one indeed, not only because of the horrendous
casualty figures, but because there are so many variables.
If you’re looking for further reading (in additional to the citations already provided) I’d suggest, as “light” reading, the book “Pulling
Through” by Dean C. Ing.